50-70-4

Basic information

• Product Name: Sorbitol
• Synonyms: A-625/641ABS 301K;A-625/641ABS 500FR-1;Cholaxine;component of Probilagol;Cystosol;Diakarmon;D-Sobit;d-Sorbite
• CAS NO: 50-70-4
• Molecular Formula: C₆H₁₄O₆
• Molecular Weight: 182.17
• EINECS: 200-061-5
• Product Categories: Biochemistry;Glucose;Sugar Alcohols;Sugars;Food additives;Dextrins、Sugar & Carbohydrates;Food & Flavor Additives;RESULAX;Food addivite and Sweeteners;Inhibitors
• Mol File: 50-70-4.mol
• Article Data: 224

Chemical Properties

• Melting Point: 98-100 °C(lit.)
• Boiling Point: bp760 105°
• Flash Point: >100°C
• Appearance: White/liquid
• Density: 1.28 g/mL at 25 °C
• Vapor Density: <1 (vs air)
• Vapor Pressure: <0.1 mm Hg ( 25 °C)
• Refractive Index: n20/D 1.46
• Storage Temp.: Store at RT.
• Solubility: H2O: 1 M at 20 °C, clear, colorless
• PKA: pKa (17.5°): 13.6
• Water Solubility: SOLUBLE
• Sensitive: Hygroscopic
• Stability: Stable. Avoid strong oxidizing agents. Protect from moisture.
• Merck: 14,8725
• BRN: 1721899
• CAS DataBase Reference: Sorbitol(CAS DataBase Reference)
• NIST Chemistry Reference: Sorbitol(50-70-4)
• EPA Substance Registry System: Sorbitol(50-70-4)

Safety Data

• Hazard Codes: Xi
• Statements: 36/37/38
• Safety Statements: 8-36-26-24/25
• WGK Germany: 2
• RTECS: LZ4290000
• F: 3
• TSCA: Yes
• Hazardous Substances Data: 50-70-4(Hazardous Substances Data)

Usage

Product Features

Sorbitol is a non-volatile polyhydric sugar alcohol. It is chemically stable and not easily to be oxidized by air. It is easily soluble in water, hot ethanol, methanol, isopropanol, butanol alcohol, cyclohexanol, phenol, acetone, acetic acid and dimethyl formamide. It is widely distributed in nature plant fruit. It is not easy to be fermented by various kinds of microorganism and have a excellent heat resistance without decomposing even at high temperature (200 °C). It is initially separated from the mountain strawberry by the Boussingault (French) et al. The pH value of the saturated aqueous solution is 6 to 7. It is isomer of mannitol, Taylor alcohol, and galactose alcohol. It has a refreshing sweet taste with sweetness being 65% of sucrose. It has excellent moisture absorption capability with a low calorific value and has very wide range of effects on the food, cosmetic, pharmaceutical field. When applied in food, it can prevent the food drying, aging, and can extend the shelf life of products as well as effectively prevent the precipitation of sugars and salts contained in the foods and thus maintain the strength balance of sweetness, sour, bitter and enhance food flavor. It can be synthesize from the hydrogenation of glucose under heating and high pressure with the existence of nickel catalyst.

Uses

Different sources of media describe the Uses of 50-70-4 differently. You can refer to the following data:
1. 1. Daily chemical industry Sorbitol can be used as an excipient, moisturizing agents, and antifreeze agents in toothpaste, with the added amount being up to 25 to 30%. This can help maintain the lubrication, color, and good taste for the paste. In cosmetics field, it is used as an anti-drying agent (substitute glycerol) which can enhance the stretch and lubricity of emulsifier, and thus is suitable for long-term storage; Sorbitan esters and sorbitan fatty acid ester as well as its ethylene oxide adducts having a advantage of a small skin irritation which is thus widely used in the cosmetics industry. 2. The food industry Adding sorbitol into foods can prevent the drying of food and make food stay fresh and soft. Application in bread cake has a significant effect. The sweetness of sorbitol is lower than that of sucrose, and can’t be exploited by any bacteria. It is an important raw material for production of sugar-free candy and a variety of anti-caries food. Since the metabolism of the product does not cause increase of blood sugar, it can also be applied as a sweetener agent and nutrient agent for the food of patients with diabetes. Sorbitol does not contain an aldehyde group and is not easily oxidized. It will not have Maillard reaction with amino acids upon heating. It also has certain physiological activity. It can prevent the denaturation of the carotenoids and edible fats and protein; adding this product to the concentrated milk can extend the shelf life; it can also be used to improve the color, flavor and taste of small intestine and has significant stabilizing effect and long-term storage effect on fish pate. Similar effect can also be observed in the jam. 3. the pharmaceutical industry Sorbitol can be used as raw material in vitamin C; also can be used as feed syrup, injection fluids, and raw material of medicine tablet; as a drug dispersion agent and fillers, cryoprotectants, anti-crystallizing agent, medicine stabilizers, wetting agents, capsules plasticized agents, sweetening agents, and ointment matrix. 4. the chemical industry Sorbitol abietin is often used as the raw material for common architectural coatings, also used as plasticizers and lubricants for application in polyvinyl chloride resin and other polymers. It can from complex with iron, copper, and aluminum ion in alkaline solution to be applied to the washing and bleaching in textile industry. Using sorbitol and propylene oxide as a starting material can produce rigid polyurethane foam as well as have some flame retardant properties. The above information is edited by the lookchem of Dai Xiongfeng.
2. D-Sorbitol is a sugar alcohol that is naturally found in Toyon berries. D-Sorbitol is used to increase stability of silver nanoparticles and is also used as a sugar substitute.
3. Sorbitol is a humectant that is a polyol (polyhydric alcohol) produced by hydrogenation of glucose with good solubility in water and poor solubility in oil. It is approximately 60% as sweet as sugar, and has a caloric value of 2.6 kcal/g. It is highly hygroscopic and has a pleasant, sweet taste. It maintains moistness in shredded coconut, pet foods, and candy. In sugarless frozen desserts, it depresses the freezing point, adds solids, and contributes some sweetness. It is used in low-calorie beverages to provide body and taste. It is used in dietary foods such as sugarless candy, chewing gum, and ice cream. It is also used as a crystallization modifier in soft sugar-based confections.
4. In manufacture of sorbose, ascorbic acid, propylene glycol, synthetic plasticizers and resins; as humectant (moisture conditioner) on printing rolls, in leather, tobacco. In writing inks to insure a smooth flow and to prevent crusting on the point of the pen. In antifreeze mixtures with glycerol or glycols. In candy manufacture of to increase shelf life by retarding the solidification of sugar; as humectant and softener in shredded coconut and peanut butter; as texturizer in foods; as sequestrant in soft drinks and wines. Used to reduce the undesirable aftertaste of saccharin in foodstuffs; as sugar substitute for diabetics. Pharmaceutic aid (flavor; tablet excipient); to increase absorption of vitamins and other nutrients in pharmaceutical preparations: Chem. Eng. News 36, 59 (Feb. 24, 1958).

Toxicity

LD50 orally in Rabbit: 15900 mg/kg

Limited use

FAO/WHO: raisins, 5g/kg; Edible ices and ice drink: 50g/kg (alone or the amount of its combination with glycerol). FDA, §184.1835 (2000): 99% hard candy; gum 75%, candy 98%; jams, jellies, 30%; frozen dairy dessert 17%; bakery products 30%; other food 2%. FEMA (mg/kg): 1300 Soft drinks; cold drink 70,000; candy 21000; bakery 50000; pudding category 8000; sugar-coat 500; top Decorating 280,000. GB 2760-2000: with the "02319, maltitol."

Chemical Properties

Different sources of media describe the Chemical Properties of 50-70-4 differently. You can refer to the following data:
1. It is white and odorless crystalline powder with sweet taste and being hygroscopic. It can be dissolved in water (235g/100g water, 25 °C), glycerin, and propylene glycol; and is slightly soluble in methanol, ethanol, acetic acid, and phenol and acetamide solution but almost insoluble in most other organic solvents.
2. d-Sorbitol has a sweet taste. In comparison to sucrose, the relative sweetness of sorbitol is approximately 50%. Sorbitol can exist in any of several crystalline forms with melting points ranging from 89 to 101°C. For a detailed description of this compound, refer to Burdock (1997).
3. White or almost white, crystalline powder.
4. Sorbitol is D-glucitol. It is a hexahydric alcohol related to mannose and is isomeric with mannitol. Sorbitol occurs as an odorless, white or almost colorless, crystalline, hygroscopic powder. Four crystalline polymorphs and one amorphous form of sorbitol have been identified that have slightly different physical properties, e.g. melting point. Sorbitol is available in a wide range of grades and polymorphic forms, such as granules, flakes, or pellets that tend to cake less than the powdered form and have more desirable compression characteristics. Sorbitol has a pleasant, cooling, sweet taste and has approximately 50–60% of the sweetness of sucrose.

Production method

1. Pour the prepared 53% aqueous solution of glucose into the autoclave, adding the nickel catalyst of 0.1% the weight of glucose; after replacement of the air, add hydrogen at about 3.5MPa, 150 °C, and pH8.2-8.4; control the endpoint with residual sugar content being lower than 0.5%. After precipitation for 5 min, put the resulting solution of sorbitol through ion exchange resin to obtain the refined product. Material fixed consumption amount: hydrochloric acid 19kg/t, caustic 36kg/ t, solid base 6kg/t, aluminum-nickel alloy powder 3kg/t, orally administrated glucose 518kg/t, activated carbon 4kg/t. 2. It is obtained from the hydrogenation of glucose with the nickel catalyst at high temperature and high pressure after which the product is further refined through the ion exchange resin, concentrated,crystallized, and, separated to obtain the final product. 3. Domestic production of sorbitol mostly applied continuously or intermittently hydrogenation of refined glucose obtained from starch saccharification: C6H12O6 + H2 [Ni] → C6H14O6 Pour the prepared 53% aqueous solution of glucose into the autoclave, adding the nickel catalyst of 0.1% the weight of glucose; after replacement of the air, add hydrogen at about 3.5MPa, 150 °C, and pH8.2-8.4; control the endpoint with residual sugar content being lower than 0.5%. After precipitation for 5 min, put the resulting solution of sorbitol through ion exchange resin to obtain the refined product. The above-mentioned process is simple without the necessity of isolation before obtaining qualified products as well as without "three wastes" pollution. However, for the starch, the yield is only 50%, and thus has a higher cost. Introduction of new technology by direct hydrogenation on starch saccharification liquid can obtain a yield up to 85%.

Originator

Sorbitol,Memphis Co.

Occurrence

Sorbitol is one of the most widely found sugar alcohols in nature with relatively high concentrations occurring in apples, pears, plums, peaches and apricots. Also reported found in several varieties of berries, seaweed and algae.

Definition

Different sources of media describe the Definition of 50-70-4 differently. You can refer to the following data:
1. ChEBI: The D-enantiomer of glucitol (also known as D-sorbitol).
2. A hexahydric alcohol that occurs in rose hips and rowan berries. It can be synthesized by the reduction of glucose. Sorbitol is used to make vitamin C (ascorbic acid) and surfactants. It is also used in medicines and as a sweetener (particularly in foods for diabetics). It is an isomer of mannitol.
3. A polyhydric alcohol, CH2OH(CHOH)4CH2OH, derived from glucose; it is isomeric with mannitol. It is found in rose hips and rowan berries and is manufactured by the catalytic reduction of glucose with hydrogen. Sorbitol is used as a sweetener (in diabetic foods) and in the manufacture of vitamin C and various cosmetics, foodstuffs, and medicines.

Production Methods

Sorbitol occurs naturally in the ripe berries of many trees and plants. It was first isolated in 1872 from the berries of the Mountain Ash (Sorbus americana). Industrially, sorbitol is prepared by high-pressure hydrogenation with a copper–chromium or nickel catalyst, or by electrolytic reduction of glucose and corn syrup. If cane or beet sugars are used as a source, the disaccharide is hydrolyzed to dextrose and fructose prior to hydrogenation.

Preparation

Sorbitol is manufactured by hydrogenation of glucose with hydrogen and active nickel catalyst. It is commercially available as 70% syrup or as a pure white powder.

Manufacturing Process

20 ml of a suspension of CTAB-permeabilized cells of Zymomonas mobilis were mixed with 80 ml of a 4% carrageenan solution and the mixture was poured into shallow dishes and allowed to rigidify. The rigidified immobilizate was then divided into 3x3x3 mm cubes, exposed to a solution of 0.3 M KCl overnight and then divided into batches and exposed to one of the following treatments:(A) Cubes stabilized with potassium ions were used without further treatment for production of sorbitol/gluconic acid.(B) Cubes were incubated with a 1.0% solution of polyethyleneimine at room temperature for 30 min and then treated with glutaraldehyde at 4°C for 30 min.Comparison of two rigidification methods:A volume of 450 ml of cubes treated by the method described in (A) were reacted in a 1.5 liter fluidized bed fermenter with a substrate solution comprised of 100 g/L glucose, 100 g/L fructose and a protein concentration of 6.1 g/L, at a D of 0.053 h-1, and titrated with 3 N KOH. After 48 hours, 68.8% of the substrate was converted with a resulting production of 3.65 g sorbitol/L*h and 0.6 g sorbitol/g protein*h. After approximately 50 days, the productivity of the fermenter was reduced by about one half.Cubes treated as described (B) using glutaraldehyde at a concentration of 0.5%, were reacted in a 1.6 liter fermenter with a substrate solution comprised of 100 g/L glucose, 100 g/L fructose and a protein concentration of 8.6 g/L, at a D of 0.055 h-1, and titrated with 3 N KOH. After 48 hours, 90.0% of the substrate was converted with a resulting production of 4.95 g sorbitol/L*h and 0 58 g sorbitol/g protein*h. After 75 days, the productivity of the fermenter was reduced by only 3.5%.

Brand name

Sorbo (ICI Americas).

Therapeutic Function

Cholecystokinetic, Diuretic, Pharmaceutic aid

General Description

Odorless colorless solid. Sinks and mixes with water.

Air & Water Reactions

Water soluble.

Reactivity Profile

D-Sorbitol is an alcohol. Flammable and/or toxic gases are generated by the combination of alcohols with alkali metals, nitrides, and strong reducing agents. They react with oxoacids and carboxylic acids to form esters plus water. Oxidizing agents convert them to aldehydes or ketones. Alcohols exhibit both weak acid and weak base behavior. They may initiate the polymerization of isocyanates and epoxides.

Health Hazard

Hot liquid will burn skin.

Pharmaceutical Applications

Sorbitol is widely used as an excipient in pharmaceutical formulations. It is also used extensively in cosmetics and food products. Sorbitol is used as a diluent in tablet formulations prepared by either wet granulation or direct compression. It is particularly useful in chewable tablets owing to its pleasant, sweet taste and cooling sensation. In capsule formulations it is used as a plasticizer for gelatin. Sorbitol has been used as a plasticizer in film formulations. In liquid preparations sorbitol is used as a vehicle in sugar-free formulations and as a stabilizer for drug, vitamin, and antacid suspensions. Furthermore, sorbitol is used as an excipient in liquid parenteral biologic formulations to provide effective protein stabilization in the liquid state. It has also been shown to be a suitable carrier to enhance the in vitro dissolution rate of indometacin. In syrups it is effective in preventing crystallization around the cap of bottles. Sorbitol is additionally used in injectable and topical preparations, and therapeutically as an osmotic laxative. Sorbitol may also be used analytically as a marker for assessing liver blood flow.

Biochem/physiol Actions

D-Sorbitol is a sugar alcohol that is commonly used as a sugar substitute. It occurs naturally and is also produced synthetically from glucose. The food industry uses D-sorbitol as an additive in the form of a sweetener, humectant, emulsifier, thickener, or dietary supplement. D-Sorbitol has also been found in cosmetics, paper, and pharmaceuticals. Naturally, D-sorbitol occurs widely in plants via photosynthesis, ranging from algae to higher order fruits of the family Rosaceae.

Safety Profile

Mildly toxic by ingestion. Human systemic effects by ingestion: hypermotility and diarrhea. Mutation data reported. When heated to decomposition it emits acrid smoke and irritating fumes.

Safety

Sorbitol is widely used in a number of pharmaceutical products and occurs naturally in many edible fruits and berries. It is absorbed more slowly from the gastrointestinal tract than sucrose and is metabolized in the liver to fructose and glucose. Its caloric value is approximately 16.7 J/g (4 cal/g). Sorbitol is better tolerated by diabetics than sucrose and is widely used in many sugar-free liquid vehicles. However, it is not considered to be unconditionally safe for diabetics. Reports of adverse reactions to sorbitol are largely due to its action as an osmotic laxative when ingested orally,(17–19) which may be exploited therapeutically. Ingestion of large quantities of sorbitol (>20 g/day in adults) should therefore be avoided. Sorbitol is not readily fermented by oral microorganisms and has little effect on dental plaque pH; hence, it is generally considered to be noncariogenic. Sorbitol is generally considered to be more irritating than mannitol. LD50 (mouse, IV): 9.48 g/kg LD50 (mouse, oral): 17.8 g/kg LD50 (rat, IV): 7.1 g/kg LD50 (rat, SC): 29.6 g/kg

storage

Sorbitol is chemically relatively inert and is compatible with most excipients. It is stable in air in the absence of catalysts and in cold, dilute acids and alkalis. Sorbitol does not darken or decompose at elevated temperatures or in the presence of amines. It is nonflammable, noncorrosive, and nonvolatile. Although sorbitol is resistant to fermentation by many microorganisms, a preservative should be added to sorbitol solutions. Solutions may be stored in glass, plastic, aluminum, and stainless steel containers. Solutions for injection may be sterilized by autoclaving. The bulk material is hygroscopic and should be stored in an airtight container in a cool, dry place.

Purification Methods

Crystallise D(-)-sorbitol (as hemihydrate) several times from EtOH/water (1:1), then dry it by fusing and storing over anhydrous MgSO4. [Koch et al. J Am Chem Soc 75 953 1953, Beilstein 1 IV 2839.]

Incompatibilities

Sorbitol will form water-soluble chelates with many divalent and trivalent metal ions in strongly acidic and alkaline conditions. Addition of liquid polyethylene glycols to sorbitol solution, with vigorous agitation, produces a waxy, water-soluble gel with a melting point of 35–40℃. Sorbitol solutions also react with iron oxide to become discolored. Sorbitol increases the degradation rate of penicillins in neutral and aqueous solutions.

Regulatory Status

GRAS listed. Accepted for use as a food additive in Europe. Included in the FDA Inactive Ingredients Database (intra-articular and IM injections; nasal; oral capsules, solutions, suspensions, syrups and tablets; rectal, topical, and vaginal preparations). Included in parenteral and nonparenteral medicines licensed in the UK. Included in the Canadian List of Acceptable Non-medicinal Ingredients.

InChI:InChI=1/C6H14O6/c7-1-3(9)5(11)6(12)4(10)2-8/h3-12H,1-2H2/t3-,4+,5-,6-/m1/s1

Synthetic route

D-glucose (50-99-7) → D-sorbitol (50-70-4)

Conditions	Yield
With hydrogen In water at 120℃; under 15001.5 Torr; for 1h;	100%
With hydrogen; ruthenium embedded in mesoporous carbon In water at 120℃; under 15001.5 Torr; for 2h; Catalytic behavior; Reagent/catalyst; Inert atmosphere; Autoclave;	99.3%
With hydrogen at 120℃; under 22502.3 Torr; for 2h; high pressure reactor;	94.43%

methyl D-glucopyranoside (97-30-3, 617-04-9, 709-50-2, 1824-94-8, 2152-78-5, 3396-99-4, 6819-48-3, 18469-06-2, 20550-04-3, 22277-65-2, 29411-57-2, 35437-40-2, 35437-43-5, 36191-11-4, 36191-12-5, 39598-79-3, 39598-80-6, 39598-89-5, 51023-63-3, 51223-62-2, 51224-38-5, 51224-39-6, 51224-40-9, 51224-41-0, 51819-81-9, 51819-82-0, 51819-83-1, 56688-81-4, 62279-53-2, 64281-79-4, 64281-80-7, 64912-19-2, 66101-73-3, 78184-90-4, 84368-39-8, 84368-40-1, 84368-41-2, 92142-37-5, 93302-26-2, 103421-28-9, 115794-08-6, 3149-68-6) → D-sorbitol (50-70-4)

Conditions	Yield
With ruthenium-carbon composite; hydrogen In water at 180℃; under 43958.7 Torr; for 3h; Temperature; Autoclave;	100%

D-Glucose (2280-44-6) → D-sorbitol (50-70-4)

Conditions	Yield
With hydrogen In water at 100℃; under 37503.8 Torr; for 2h; Catalytic behavior; Reagent/catalyst; Pressure; Time; Autoclave;	99%
With water; hydrogen at 120℃; under 22502.3 Torr; for 5h; Catalytic behavior; Reagent/catalyst; Temperature; Pressure; Time; High pressure;	98%
With formic acid; sodium formate; C22H26ClN2Rh(1+)*BF4(1-) In water; toluene at 80℃; for 48h; pH=4.4; Temperature; Inert atmosphere; Schlenk technique; Sealed tube;	95%

Maltose (133-99-3, 490-37-9, 2152-98-9, 4482-75-1, 5965-66-2, 13299-27-9, 13360-52-6, 14641-93-1, 15548-43-3, 16462-44-5, 16984-36-4, 16984-38-6, 20869-27-6, 22688-72-8, 27452-49-9, 29276-55-9, 30608-12-9, 34481-13-5, 37169-60-1, 37169-64-5, 64234-01-1, 64234-02-2, 75281-88-8, 80446-85-1, 84413-57-0, 92344-56-4, 93221-87-5, 93301-77-0, 94799-29-8, 100427-98-3, 100428-00-0, 101312-82-7, 102046-24-2, 102046-25-3, 109432-00-0, 109432-02-2, 109432-04-4, 109432-08-8, 135268-49-4, 138231-26-2, 140461-59-2, 145414-22-8, 145414-26-2, 146339-75-5, 146339-76-6, 149116-55-2, 6363-53-7) → D-sorbitol (50-70-4)

Conditions	Yield
With zinc(II) chloride tetrahydrate; 5% active carbon-supported ruthenium; hydrogen at 130℃; under 30003 Torr; for 6h; Time;	97%

levoglucosan (498-07-7) → D-sorbitol (50-70-4)

Conditions	Yield
With water; hydrogen at 180℃; under 37503.8 Torr; for 5h; Catalytic behavior; Pressure; Autoclave;	96.2%
Multi-step reaction with 2 steps 1: hydrogen; water / 37503.8 Torr / Autoclave 2: hydrogen / water / 5 h / 180 °C / 52505.3 Torr / Autoclave View Scheme
Multi-step reaction with 2 steps 1: hydrogen; water / 37503.8 Torr / Autoclave 2: hydrogen; 5 wt% ruthenium/carbon / water / 5 h / 180 °C / 52505.3 Torr / Autoclave View Scheme

Cellobiose (13360-52-6) → D-sorbitol (50-70-4)

Conditions	Yield
With hydrogen In water at 150℃; under 15001.5 Torr; for 10h; Reagent/catalyst; Temperature; Autoclave;	95.1%
With water; hydrogen at 180℃; under 37503.8 Torr; for 5h; Autoclave;	91.1%
With water; hydrogen at 180℃; under 37503.8 Torr; for 5h; Reagent/catalyst; High pressure;	86%

D-Fructose (57-48-7) → mannitol (69-65-8) + D-sorbitol (50-70-4)

Conditions	Yield
With hydrogen In butan-1-ol at 120℃; under 26252.6 Torr; for 10h; Reagent/catalyst; Pressure; Temperature; Solvent;	A 93% B 5%
With hydrogen In butan-1-ol at 120℃; under 18751.9 Torr; for 5h; Pressure; Reagent/catalyst; Temperature; Solvent;	A 62% B 14%
With Butane-1,4-diol; Cu3Ni3Al2 In water at 149.84℃; pH=9 - 10;	A 60% B 16%

D-(+)-cellobiose → mannitol (69-65-8) + D-sorbitol (50-70-4)

Conditions	Yield
With hydrogen In water at 19.84 - 189.84℃; under 37503.8 Torr; for 3h; Reagent/catalyst; Temperature; Time; Autoclave;	A n/a B 91.5%

sucrose octakis(trimethylsilyl) ether (19159-25-2) → mannitol (69-65-8) + D-sorbitol (50-70-4) + 1,5-anhydro-D-glucitol (154-58-5)

Conditions	Yield
Stage #1: sucrose octakis(trimethylsilyl) ether With bis(pentafluorophenyl)borinic acid; 1,1,3,3-tetramethyldisilazane In chloroform-d1 at 25℃; for 3h; Inert atmosphere; Glovebox; Stage #2: In methanol Inert atmosphere; Glovebox;	A n/a B n/a C 90%

Maltose (133-99-3, 490-37-9, 2152-98-9, 4482-75-1, 5965-66-2, 13299-27-9, 13360-52-6, 14641-93-1, 15548-43-3, 16462-44-5, 16984-36-4, 16984-38-6, 20869-27-6, 22688-72-8, 27452-49-9, 29276-55-9, 30608-12-9, 34481-13-5, 37169-60-1, 37169-64-5, 64234-01-1, 64234-02-2, 75281-88-8, 80446-85-1, 84413-57-0, 92344-56-4, 93221-87-5, 93301-77-0, 94799-29-8, 100427-98-3, 100428-00-0, 101312-82-7, 102046-24-2, 102046-25-3, 109432-00-0, 109432-02-2, 109432-04-4, 109432-08-8, 135268-49-4, 138231-26-2, 140461-59-2, 145414-22-8, 145414-26-2, 146339-75-5, 146339-76-6, 149116-55-2) → mannitol (69-65-8) + D-sorbitol (50-70-4)

Conditions	Yield
With hydrogen; Nafion; ruthenium In water at 150℃; under 37503 Torr; for 5h;	A 7.1% B 87.6%

D-glucose (50-99-7) → mannitol (69-65-8) + D-sorbitol (50-70-4)

Conditions	Yield
With hydrogen; Ru/C In water at 120℃; under 15001.5 Torr; for 2h; Catalytic behavior; Inert atmosphere; Autoclave;	A 12.6% B 86.3%
With hydrotalcite; Pt/γ-Al2O3; hydrogen In water at 90℃; under 12001.2 Torr; for 4h; Catalytic behavior; Time; Green chemistry;	A 14% B 54%
With platinum Hydrogenation;

methyl D-glucopyranoside (97-30-3, 617-04-9, 709-50-2, 1824-94-8, 2152-78-5, 3396-99-4, 6819-48-3, 18469-06-2, 20550-04-3, 22277-65-2, 29411-57-2, 35437-40-2, 35437-43-5, 36191-11-4, 36191-12-5, 39598-79-3, 39598-80-6, 39598-89-5, 51023-63-3, 51223-62-2, 51224-38-5, 51224-39-6, 51224-40-9, 51224-41-0, 51819-81-9, 51819-82-0, 51819-83-1, 56688-81-4, 62279-53-2, 64281-79-4, 64281-80-7, 64912-19-2, 66101-73-3, 78184-90-4, 84368-39-8, 84368-40-1, 84368-41-2, 92142-37-5, 93302-26-2, 103421-28-9, 115794-08-6, 3149-68-6) → D-sorbitol (50-70-4) + 1,2,5,6-hexanetetrol (20221-50-5, 24211-51-6, 122923-46-0, 5581-21-5)

Conditions	Yield
With hydrogen; copper In water at 225℃; under 43958.7 Torr; for 3h; Autoclave;	A 85% B 15%

Maltose (133-99-3, 490-37-9, 2152-98-9, 4482-75-1, 5965-66-2, 13299-27-9, 13360-52-6, 14641-93-1, 15548-43-3, 16462-44-5, 16984-36-4, 16984-38-6, 20869-27-6, 22688-72-8, 27452-49-9, 29276-55-9, 30608-12-9, 34481-13-5, 37169-60-1, 37169-64-5, 64234-01-1, 64234-02-2, 75281-88-8, 80446-85-1, 84413-57-0, 92344-56-4, 93221-87-5, 93301-77-0, 94799-29-8, 100427-98-3, 100428-00-0, 101312-82-7, 102046-24-2, 102046-25-3, 109432-00-0, 109432-02-2, 109432-04-4, 109432-08-8, 135268-49-4, 138231-26-2, 140461-59-2, 145414-22-8, 145414-26-2, 146339-75-5, 146339-76-6, 149116-55-2) → α-D-glucopyranose-(1→3)-D-mannitol (79355-25-2) + mannitol (69-65-8) + D-sorbitol (50-70-4)

Conditions	Yield
With hydrogen; Ru-carbon In water at 145℃; under 37503 Torr; for 7h;	A 10.8% B 2.8% C 83.7%
With hydrogen; ruthenium In water at 145℃; under 37503 Torr; for 6h;	A 14.6% B 14.6% C 78.2%
With hydrogen; ruthenium In water at 145℃; under 37503 Torr; for 6h;	A 14.6% B 3.8% C 78.2%

Upstream product

• 10227-29-9 methyl 2,3-di-O-methyl-α-D-glucopyranoside 
• 2280-44-6 D-Glucose 
• 20942-96-5 α-D-glucopyranosyl-(1->6)-D-gulitol 
• 87-79-6 L-sorbose 
• 53-57-6 NADPH 
• 534-73-6 isomaltitol 
• 9004-34-6 cellulose 
• 13360-52-6 Cellobiose 
• 535-94-4 β-D-Glcp-(1->4)-D-glucitol 
• 492-61-5 β-D-glucose 
• 64-19-7 acetic acid 
• 652-67-5 Isosorbide 
• 1159579-93-7 calogenin 20-O-β-D-glucopyranosyl-3-O-β-D-thevetopyranosyl-(1->4)-β-D-oleandropyranoside 
• 57-48-7 D-Fructose 

Downstream Products

• 107-02-8 acrolein 
• 501-30-4 5-hydroxy-2-(hydroxymethyl)-4H-pyran-4-one 
• 57-48-7 D-Fructose 
• 10326-41-7 D-Lactic acid 
• 50-99-7 D-glucose 
• 4435-50-1 butane-1,2,3-triol 
• 57-55-6 propylene glycol 
• 87-79-6 L-sorbose 
• 6027-89-0 L-gulose 
• 50-99-7 glucose 
• 7208-47-1 1,2,3,4,5,6-hexa-O-acetyl-D-glucitol 
• 6591-58-8 sorbitol hexanitrate 
• 144-62-7 oxalic acid 
• 90114-15-1 O¹,O³;O²,O⁴-dimethanediyl-D-glucitol 

Relevant articles and documents

THE PAIRED ELECTROCHEMICAL SYNTHESIS OF GLUCONIC ACID AND SORBITOL

Gluconic acid and sorbitol are obtained simultaneously both with 90percent yields by paired electolysis of glucose, with a Pb sheet cathode and a dimension stable anode (DSA) in a press filtration diaphragm cell.The anolyte is composed from 66.7percent glucose and 2percent NaBr, and the catholyte from 66.7percent glucose and 2.5percent Na2SO4, respectively.The electrolysis was performed at the temperature of 60 deg C, at the current density of 50 mA cm-2, Qr is 110percent.At this optimum conditions the current efficiencies for both gluconic acid and sorbitol are higher than 80percent.

Bimetallic Ru:Ni/MCM-48 catalysts for the effective hydrogenation of D-glucose into sorbitol

Three different bimetallic Ru:Ni catalysts supported on a mesoporous silica MCM-48 were prepared by consecutive wet impregnations, with a total metal loading of ca. 3% (w w?1). Ru:Ni ratios spanned in the range of 0.15–1.39 (w w?1) and were compared with the corresponding monometallic Ni/MCM-48. The catalysts so prepared were characterized by X-Ray Diffraction, Transmission Electron Microscopy, adsorption/desorption of N2, Temperature Programmed Reduction, NH3 ? TPD and Atomic Absorption, and tested in the liquid phase hydrogenation of D-glucose into sorbitol in the temperature range 120–140 °C under 2.5 MPa of H2 pressure. Bimetallic catalysts with Ru:Ni ratios higher than 0.45 enhanced the catalytic behavior of the monometallic Ni/MCM-48 in the reaction, increasing the reaction rate and showing complete selectivity to sorbitol by minimizing the production of mannitol. Ru:Ni/MCM-48 (0.45) was recovered from the reaction media and tested for three reaction cycles, showing good stability under the selected experimental conditions.

Transfer hydrogenation of cellulose to sugar alcohols over supported ruthenium catalysts

Ru/C catalysts are active for the conversion of cellulose using 2-propanol or H2 of 0.8 MPa as sources of hydrogen, whereas the Ru/Al 2O3 catalyst is inactive in both reactions, indicating that the Ru/C catalysts are remarkably effective for the cellulose conversion.

Structural characterization and anti-inflammatory activity of a linear β-d-glucan isolated from Pleurotus sajor-caju

Glucans comprise an important class of polysaccharides present in basidiomycetes with potential biological activities. A (1 → 3)-β-d-glucan was isolated from Pleurotus sajor-caju via extraction with hot water followed by fractionation by freeze-thawing and finally by dimethyl sulfoxide extraction. The purified polysaccharide showed a 13C-NMR spectrum with six signals consisting of a linear glucan with a β-anomeric signal at 102.8 ppm and a signal at 86.1 ppm relative to O-3 substitution. The other signals at 76.2, 72.9, 68.3, and 60.8 ppm were attributed to C5, C2, C4, and C6, respectively. This structure was confirmed by methylation analysis, and HSQC studies. The β-d-glucan from P. sajor-caju presented an immunomodulatory activity on THP-1 macrophages, inhibited the inflammatory phase of nociception induced by formalin in mice, and reduced the number of total leukocytes and myeloperoxidase levels induced by LPS. Taken together, these results demonstrate that this β-d-glucan exhibits a significant anti-inflammatory activity.

Pt nanocatalysts supported on reduced graphene oxide for selective conversion of cellulose or cellobiose to sorbitol

Pt nanocatalysts loaded on reduced graphene oxide (Pt/RGO) were prepared by means of a convenient microwave-assisted reduction approach with ethylene glycol as reductant. The conversion of cellulose or cellobiose into sorbitol was used as an application reaction to investigate their catalytic performance. Various metal nanocatalysts loaded on RGO were compared and RGO-supported Pt exhibited the highest catalytic activity with 91.5 % of sorbitol yield from cellobiose. The catalytic performances of Pt nanocatalysts supported on different carbon materials or on silica support were also compared. The results showed that RGO was the best catalyst support, and the yield of sorbitol was as high as 91.5 % from cellobiose and 58.9 % from cellulose, respectively. The improvement of catalytic activity was attributed to the appropriate Pt particle size and hydrogen spillover effect of Pt/RGO catalyst. Interestingly, the size and dispersion of supported Pt particles could be easily regulated by convenient adjustment of the microwave heating temperature. The catalytic performance was found to initially increase and then decrease with increasing particle size. The optimum Pt particle size was 3.6 nm. These findings may offer useful guidelines for designing novel catalysts with beneficial catalytic performance for biomass conversion. Support group: Pt nanocatalysts loaded on reduced graphene oxide are prepared by a microwave-assisted ethylene glycol reduction method, and present high activity and selectivity for the conversion of cellobiose or cellulose to sorbitol. The high catalytic activity is attributed to the synergistic effects of reduced graphene oxide and the supported Pt nanoparticles.

Glucose Hydrogenation to Sorbitol over a Skeletal Ni-P Amorphous Alloy Catalyst (Raney Ni-P)

A skeletal Ni-P amorphous alloy catalyst (Raney Ni-P) was prepared by alkali leaching of a Ni-Al-P amorphous precursor obtained by the rapid quenching technique of a melting solution containing Ni, Al, and P. This catalyst showed higher turnover rates (per surface Ni atom) than Raney Ni for the hydrogenation of glucose to sorbitol, apparently as a result of promotion of Ni-active sites by phosphorus. The Raney Ni-P catalysts gave turnover rates similar to those measured on Ni-P amorphous alloys without Al, but they had a significantly higher density of Ni surface atoms. As a result, Raney Ni-P catalysts showed superior specific hydrogenation rates (per gram catalyst) than either Raney Ni or Ni-P amorphous alloys.

Glucose hydrogenation in a trickle-bed reactor

Catalytic hydrogenation of 40% aqueous solutions of D-glucose to D-glucitol was studied in a high-pressure trickle-bed reactor. The reactions were performed on a supported nickel catalyst at temperatures ranging from 115 to 165°C and in the pressure range 0.5 to 10 MPa. The order of the reaction with respect to hydrogen is 0.65 and apparent activation energy 23.8-48.5 kJ mol-1, the latter depending on initial molar glucose concentration and density and viscosity of the solution. The influence of external diffusion is necessary to take into account for scaling-up the process.

Efficient conversion of D-glucose into D-sorbitol over MCM-41 supported Ru catalyst prepared by a formaldehyde reduction process

Ru/MCM-41 catalyst prepared by an impregnation-formaldehyde reduction method showed higher catalytic activity and sorbitol selectivity than other catalysts in the hydrogenation of glucose. SEM and XRD indicated the partial surface properties of Ru/MCM-41. Moreover, Ru dispersion and Ru surface area of Ru/MCM-41 were determined by pulse chemisorption, and the result further proved that Ru/MCM-41 had higher catalytic activity. A catalyst recycling experiment demonstrated that Ru/MCM-41 was a better catalyst and it could be reused three or four times. A speculated mechanism was proposed to illustrate the detailed process of d-glucose hydrogenation to produce sorbitol.

Ru/P-containing porous biochar-efficiently catalyzed cascade conversion of cellulose to sorbitol in water under medium-pressure H2 atmosphere

This paper discloses a simple and productive strategy for the preparation of biochar-based bifunctional catalysts. In this strategy, very cheap bamboo powder is thermally carbonized to yield P-containing porous biochars (PBCs) by the activation of concentrated phosphoric acid (H3PO4), and the latter can be transformed into the target catalysts via loading Ru nanometer particles (NPs) on them (marked as Ru/PBCs). A series of characterizations and measurements support that PBCs have stable and rich micro-meso pores and small strong acidic protons (0.100.28 mmol￠g11) attributable to the grafted and/or skeleton phosphorus groups, as well as a strong affinity to β-1,4-glycosidic bonds, thus exhibiting a good acid catalytic activity for the hydrolysis of cellulose to glucose. More importantly, they are excellent acidic supports for the loading of Ru NPs owing to high BET surface area, which can give the loaded Ru NPs uniform and narrow distribution (16 nm). The resulting bifunctional Ru/PBCs catalysts possess excellent hydrolytic hydrogenating activity for the one-pot cascade conversion of cellulose and the optimized conditions can achieve ca. 89% hexitol yield with 98% sorbitol selectivity under relatively mild conditions. This work provides a good example for the preparation of biomass-derived bifunctional catalysts and their applications in biorefinery.

The effect of physical morphology and the chemical state of Ru on the catalytic properties of Ru-carbon for cellulose hydrolytic hydrogenation

Ru-carbon catalysts with different physical morphologies and chemical states of Ru were prepared by different methods and used to catalyze the hydrolytic hydrogenation of cellulose at high temperatures. The physical morphology of Ru particles and the chemical state of Ru significantly influenced the catalytic performance. The Ru nanoparticles in Ru@MC prepared by thein situcarbothermal reduction method exhibited a special chemical state due to the strong interaction with carbon. The special structure could not only prevent the growth of Ru particles but also enhance the hydrogen spillover effect and improve the hydrogenation efficiency. Among the Ru-carbon catalysts, Ru@MC showed the best catalytic performance with a 72.4% yield of sorbitol. Furthermore, the embedded structure of Ru@MC stabilized the Ru nanoparticles, and the catalyst could be reused at least 6 times.

Structural features and antioxidant activity of a new galactoglucan from edible mushroom Pleurotus djamor

A new water soluble galactoglucan with apparent molecular weight ~1.61 × 105 Da, was isolated from the edible mushroom Pleurotus djamor by hot water extraction followed by purification through dialysis tubing cellulose membrane and sepharose 6B column chromatography. The sugar analysis showed the presence of glucose and galactose in a molar ratio of nearly 3:1 respectively. The structure of the repeating unit in the polysaccharide was determined through chemical and NMR experiments as:[Formula presented] In vitro antioxidant studies showed that the PDPS exhibited hydroxyl radical scavenging activity (EC50 = 1.681 ± 0.034 mg/mL), DPPH radical scavenging activity (EC50 = 3.83 ± 0.427 mg/mL), reducing power (EC50 = 4.258 ± 0.095 mg/mL), and ABTS radical quenching activity (EC50 = 0.816 ± 0.077 mg/mL). So, PDPS should be explored as a natural antioxidant.

Kinetic study of catalytic conversion of cellulose to sugar alcohols under low-pressure hydrogen

Efficient hydrolytic hydrogenation of cellulose to sugar alcohols under low H2 pressures has remained a challenge. This article deals with the conversion of cellulose by using a carbon-supported Ru catalyst under H 2 pressures as low as 0.7-0.9 MPa (absolute pressure at room temperature). Kinetic studies revealed that the Ru catalyst not only enhances the hydrolysis of cellulose to glucose and hydrogenation of glucose to sugar alcohols (sorbitol and mannitol), but also the degradation of sugar alcohols to C2-C6 polyols and gasses. The degradation path limits the total yield of sugar alcohols to less than 40 %. The yield of sugar alcohols is theoretically improved by increasing the ratio of the reaction rates of the cellulose hydrolysis, which is the rate-determining step in the reaction, to the decomposition. Thus, a mix-milling pretreatment of cellulose and the Ru catalyst together selectively accelerated the hydrolysis step and raised the yield up to 68 %, whereas the addition of acids in the cellulose conversion was less effective as a result of promotion of side-reactions. These results demonstrate superior applicability of the mix-milling treatment in the depolymerization of cellulose to its monomers. Copyright

Hydrogenation of glucose over reduced Ni/Cu/Al hydrotalcite precursors

Ni/Cu/Al hydrotalcite precursors were synthesized by a co-precipitation method. The activity of the reduced precursors for hydrogenation of glucose to sorbitol was tested. The effects of preparation methods and activation treatment on the performance of the obtained catalysts were investigated in detail. XRD and XPS tests provided the essential properties of the precursors and prepared catalysts. The properly high reduction temperature could obviously enhance catalyst activity. The conversion of glucose and selectivity to sorbitol on Ni1.85Cu1Al1.15 catalyst at 398 K were 78.4 and 93.4 %, respectively.

Polyoxometalate-supported ruthenium nanoparticles as bifunctional heterogeneous catalysts for the conversions of cellobiose and cellulose into sorbitol under mild conditions

Ru nanoparticles loaded on a Keggin-type polyoxometalate (Cs 3PW12O40), which did not possess strong intrinsic acidity, efficiently catalysed the conversions of cellobiose and cellulose into sorbitol in water medium in H2 at ≤433 K. The Bronsted acid sites generated in situ from H2 have been demonstrated to play a key role in the formation of sorbitol. The Royal Society of Chemistry 2011.

Procedure for reducing D-arabino-hexosulose to a mannitol rich mixture of D-mannitol and D-glucitol

D-arabino-Hexosulose (D-glucosone, 2) can now be conveniently produced by the enzymic reaction of pyranose-2-oxidase (P2O) with D-glucose (1).D-arabino-Hexosulose has been efficiently and selectively reduced to D-fructose (3) by catalytic hydrogenation with palladium on carbon.We now report a procedure for reducing (2) to a mannitol-rich mixture of D-mannitol (4) and D-glucitol (sorbitol, 5).The method uses catalytic hydrogenation with Raney nickel, and yields 4 and 5 in 3:1 ratio.This ratio is unlike that obtained by catalytic hydrogenation of D-glucose (which yields exclusively D-glucitol) or by catalytic hydrogenation of D-fructose (which yields 4 and 5 in 1:1 ratio).

DIRECT MEASUREMENT OF THE RATE OF RING OPENING OF D-GLUCOSE BY ENZYME-CATALYZED REDUCTION

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Structural Characterization and Immunostimulatory Activity of Polysaccharides from Brassica rapa L.

Two neutral polysaccharides (BRNP-1, 6.9 kDa; BRNP-2, 4.8 kDa) were purified from the common edible plant Brassica rapa L. via the combined techniques of ion-exchange chromatography and high-performance gel permeation chromatography. Monosaccharide composition analysis showed that BRNP-1 and BRNP-2 were composed of glucosyl residues. Methylation and 1D- and 2D-NMR analyses revealed that both BRNP-1 and BRNP-2 contained a backbone chain that was composed of α-D-(1 → 4)-linked Glcp residues and side chains that were composed of terminally linked Glcp residues attached at the O-6 position of backbone-glycosyl residues. BRNP-1 and BRNP-2, however, differed in branch degree and molecular weight. Bioassay results showed that treatment with the higher dosage (400 μg/mL) of BRNP-1 and BRNP-2 stimulated the proliferation, NO release, and cytokine secretion (IL-6 and TNF-α) of RAW264.7 macrophages. These results suggested that BRNP-1 and BRNP-2 may enhance macrophage-mediated immune responses.

Excellent activity of ultrafine Co-B amorphous alloy catalyst in glucose hydrogenation

The ultrafine Co-B amorphous alloy, doped or undoped with Mo or W, were prepared by chemical reduction with borohydride. Its catalytic performance in liquid phase hydrogenation of glucose to sorbitol has been investigated, which revealed (i)the higher activity than that of crystalline Co and the Ni-based catalysts, and (ii)the promoting effect of Mo and W dopants on the activity.

Catalytic conversion of glucose into sorbitol over niobium oxide supported Ru catalysts

Sorbitol is a sugar alcohol of great importance in cosmetic, food and pharmaceutical industry as well as the production of biopolymers. This work aimed at the synthesis of sorbitol from the hydrogenation of glucose using Ru/Nb2O5 catalysts in the amorphous and crystalline phases. The catalysts were synthesized from the wet impregnation method and characterized by N2 adsorption isotherms, TGA/DTG, EDXRF, XRD, TPR-H2, XPS and SEM. The catalytic tests presented results of high conversion rates of glucose reaching 85 % and 99 % of selectivity to sorbitol when using Nb2O5 in the crystalline form as support, and 53 % and 55 % in the conversion and selectivity, respectively, when the amorphous phase of Nb2O5 was used as support. The structural modification of the catalytic support positively favored the catalyst activity and sorbitol production, allowing the formation of nanometric particles of the active metal on the surface alongside the increase of the mesoporosity, thereby facilitating the transport of reagents.

Efficient catalytic conversion of concentrated cellulose feeds to hexitols with heteropoly acids and Ru on carbon

A combination of heteropolyacids and Ru on carbon catalyzes the conversion of concentrated cellulose feeds into hexitols under H2 pressure. Quantitative conversion of ball-milled cellulose was observed with remarkable hexitol volume productivity.

Control of selectivity, activity and durability of simple supported nickel catalysts for hydrolytic hydrogenation of cellulose

Efficient conversion of cellulose to sorbitol and mannitol by base metal catalysts is a challenge in green and sustainable chemistry, but typical supported base metal catalysts have not given good yields of hexitols or possessed durability. In this study, it has been demonstrated that a simple carbon-supported Ni catalyst affords up to 67% yield of hexitols in the conversion of cellulose, and that the catalyst is durable in the reuse experiments 7 times. In addition, the catalyst can be separated by a magnet thanks to a high content of Ni. Physicochemical analysis has indicated that the use of carbon supports has two benefits: no basicity and high water-tolerance. CeO2, ZrO2, γ-Al2O3 and TiO2 cause side-reactions due to basicity, and SiO2, γ-Al2O3 and CeO2 are less stable in hot water. Another important factor is high Ni loading as the increase of Ni content from 10 wt% to 70 wt% significantly improves the yield of hexitols and the durability of catalysts. Larger crystalline Ni particles are more resistant to sintering of Ni and surface coverage by Ni oxide species.

Glucose Hydrogenation on Ruthenium Catalysts in a Trickle-Bed Reactor

Glucose in 40 wt% aqueous solution was hydrogenated into sorbitol in a trickle-bed reactor over ruthenium catalysts supported on active charcoal pellets. The metal was loaded by cationic exchange or anionic adsorption. After reduction, ruthenium was under the form of 1-nm particles homogeneously distributed throughout the support. The reaction was conducted at 100°C under 8 MPa of hydrogen at 20 L h-1 flow rate. Conversion and selectivity to sorbitol were studied as a function of residence time. Whatever the mode of preparation, the catalysts give a total conversion of glucose with an initial specific activity of 1.1 mol h-1 g-1Ru. The selectivity to sorbitol was higher than 99.2% at 100% conversion; however, the liquid flow rate should be adjusted very accurately because any increase in the residence time results in a loss of selectivity due to epimerization of sorbitol into mannitol. The catalyst activity was stable over several weeks and no leaching of ruthenium was detected.

One-pot conversion of cellulose to isosorbide using supported metal catalysts and ion-exchange resin

One-pot conversion of cellulose to isosorbide was investigated by supported metal catalysts and ion-exchange resin in water. The maximum isosorbide yield using supported platinum catalysts and Amberlyst 70 was less than 30%. The isosorbide yield drastically increased with supported ruthenium catalysts instead of supported platinum catalysts and it also increased with the loading of ruthenium on carbon support. One-pot conversion of cellulose to isosorbide by 4 wt.% ruthenium catalyst and Amberlyst 70 proceeded with isosorbide yield of 55.8%.

Ce promoted Cu/γ-Al2O3 catalysts for the enhanced selectivity of 1,2-propanediol from catalytic hydrogenolysis of glucose

Ce promoted Cu/γ-Al2O3 catalysts were prepared with varying amounts of Cu (x = 0–10 wt%) and Ce (y = 0–15 wt%). The prepared catalysts were characterized and tested for the conversion of aqueous glucose (5 wt%) to 1,2-propanediol in a batch reactor. 10%Ce-8%Cu/γ-Al2O3 showed the complete conversion of glucose with 62.7% selectivity of 1,2-propanediol and total glycols (1,2-propanediol, ethylene glycol & 1,2-butanediol) of 81% at milder reaction conditions. Cu facilitated the hydrogenation activity and Ce loading optimize the acid/base sites of Cu/γ-Al2O3 which obtain high selectivity of 1, 2-propanediol. Catalyst reusability is reported.

HYDROGENATION OF L-SORBOSE

The invention relates to a process for L-Iditol by hydrogenating L-Sorbose. Further, the invention also relates to a use of a transition metal complex as hydrogenation catalyst for L-Sorbose. The invention relates to a process for the preparation of L-Iditol comprising at least one reaction step, in which a composition comprising L-Sorbose and hydrogen is reacted in the presence of a transition metal catalyst complex in a homogeneous solution, wherein the transition metal catalyst complex comprises at least one chiral ligand containing at least one phosphorus atom, which is capable of coordinating to the transition metal, and wherein the transition metal is selected from metals of groups 8, 9 and 10 of the periodic table of the elements according to IUPAC. The invention further relates to a use of a transition metal complex as defined above and below as hydrogenation catalyst for compositions comprising L-Iditol or mixtures thereof.

Elucidating the effect of solid base on the hydrogenation of C5 and C6 sugars over Pt–Sn bimetallic catalyst at room temperature

Conversion of sugars into sugar alcohols at room temperature with exceedingly high yields are achieved over Pt–Sn/γ-Al2O3 catalyst in the presence of calcined hydrotalcite. pH of the reaction mixture significantly affects the conversion and selectivity for sugar alcohols. Selection of a suitable base is the key to achieve optimum yields. Various solid bases in combination with Pt–Sn/γ-Al2O3 catalysts were evaluated for hydrogenation of sugars. Amongst all combinations, the mixture (1:1 wt/wt) of Pt–Sn/γ-Al2O3 and calcined hydrotalcite showed the best results. Hydrotalcite helps to make the pH of reaction mixture alkaline at which sugar molecules undergo ring opening. The sugar molecule in open chain form has carbonyl group which can be polarized by Sn in Pt–Sn/γ-Al2O3 and Pt facilitates the hydrogenation. In the current work, effect of both; solid base and Sn as a promoter has been studied to improve the yields of sugar alcohols from various C5 and C6 sugars at very mild reaction conditions.