Glucose sulfurous acid

The most popular tanning solution in current use is termed 33% basic chromium(III) sulfate and corresponds to the empirical formula CrOHSCV In older procedures, chromate was often reduced at the plant using glucose/sulfuric acid mixtures. At present, 33% basic chromium sulfate is provided as either a solution (chrome liquor) or as a commercially available powder,120 of constant, but at present slightly uncertain, chemical composition. 

Glucose Sulfuric acid Phosphoric acid Triethanolamine Tfimethylamine, diethylether, isopentane (2 5 5)... 

Monosaccharides such as glucose and fmctose are the most suitable as starting materials. When starch is used, it is first hydrolyzed with oxahc acid or sulfuric acid into a monosaccharide, mainly glucose. It is then oxidized with nitric acid in an approximately 50% sulfuric acid solution at 63—85°C in the presence of a mixed catalyst of vanadium pentoxide and iron(III) sulfate. 

Manufacture. The hydrolysis of the naturally occurring P-glycoside (saUcin) (8) with hydrochloric or sulfuric acid affords saligenin (9) and glucose (10) (eq. 11). 

Most current industrial vitamin C production is based on the efficient second synthesis developed by Reichstein and Grbssner in 1934 (15). Various attempts to develop a superior, more economical L-ascorbic acid process have been reported since 1934. These approaches, which have met with htde success, ate summarized in Crawford s comprehensive review (46). Currently, all chemical syntheses of vitamin C involve modifications of the Reichstein and Grbssner approach (Fig. 5). In the first step, D-glucose (4) is catalytically (Ni-catalyst) hydrogenated to D-sorbitol (20). Oxidation to L-sotbose (21) occurs microhiologicaRy with The isolated L-sotbose is reacted with acetone and sulfuric acid to yield 2,3 4,6 diacetone-L-sorbose,... 

CeUulose may be extracted from the ADF with 72% sulfuric acid (w/w) at 4°C for 24 h leaving an insoluble residue of lignin. The loss in mass of the ADF estimates the ceUulose component. Alternatively, ceUulose may be estimated by hydrolysis of the ADF and determination of glucose. 

FeCl3, AC2O, 55-75% yield.The relative rates of cleavage for the 6-, 3-, and 2-O-benzyl groups of a glucose derivative are 125 24 1. Sulfuric acid has also been used as a catalyst. ... 

Trichloroacetaldehyde (chloral) reacts with glucose in the presence of sulfuric acid to form two monoacetals and four diacetals. The trichloro acetal is cleaved by reduction (H2, Raney Ni, 50% NaOH, EtOH, 15 min). The trichloro acetal can probably be cleaved with Zn/AcOH [cf. ROCH(R )OCH2CCl3 cleaved by Zn/ AcOH, AcONa, 20°, 3 h, 90% yield ]. 

Trichloroacetaldehyde (chloral) reacts with glucose in the presence of sulfuric acid to form two mono- and four diacetals. ... 

The fermenters are inoculated with 7.5% by volume of a 24-hour old culture of Aspergillus sderotiorum Huber grown at 28°C in 50 ml aliquots of the above described soybean-glucose medium contained in 300 ml Erlenmeyer flasks, placed on a shaker rotating at approximately 230 rpm. The inoculated fermenters are agitated at 1,380 rpm and each aerated with 1 liter of air per minute and at a temperature of 28°C for 47 hours. A silicone antifoam is added when required. At the end of the 47-hour period, the pH of the fermentation broth rose to 6.8 to 6.9. Sulfuric acid is then added with sterile precautions to restore the pH to 6.5. 

A method developed in the MBR involved heating the cellulose with 1% sulfuric acid, from ambient to 215 °C within 2 min, maintaining this temperature for 30 s and cooling. The entire operation was completed within 4 min and afforded glucose in nearly 40% yield, along with fermentable oligomers [26]. 

Bayne, Fewster and Mitchell16 prepared VII by the method of Stacey and Turton, and recorded physical properties closely agreeing with those reported by Maurer.66 The compound was clearly related to D-glucosone, prepared from D-glucose phenylosazone and by direct oxidation, since, on treatment with dry acetone containing concentrated sulfuric acid, it gave crystalline tri-0-isopropylidene-(2-hydroxy-D-arabmo-hexose). 7... 

Neutral solutions of pure aldoses exhibit no selective absorption in the ultraviolet region103 106 such an absorption may, however, be observed108 for solutions of D-glucose and L-arabinose in 50% sulfuric acid, and is... 

Acid hydrolysis of cellulosic materials that include some hemicellulose, produces D-xylose, D-glucose, and cellobiose, as well as 11, 2-furalde-hyde (5), levulinic acid, formic acid, and acetic acid. In order to lessen the contamination due to hemicellulose, acid hydrolysis is generally performed in two steps dilute sulfuric acid (1%) at 80-120° followed by 5-20% sulfuric acid at 180°. The initial stage removes most of the pentogly-cans (pentosans). 

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