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Chemicals from Olefin Hydrocarbons
Published in James G. Speight, Handbook of Petrochemical Processes, 2019
Glycerol (1,2,3-propanetriol, CH2OHCHOHCH2OH) is a trihydric alcohol of great utility due to the presence of three hydroxyl groups. It is a colorless, somewhat viscous liquid with a sweet odor. Glycerin is the name usually used by pharmacists for glycerol. There are different routes for obtaining glycerol. It is a byproduct from the manufacture of soap from fats and oils (a nonpetroleum source). Glycerol is also produced from allyl alcohol by epoxidation using hydrogen peroxide or a peracid (similar to epoxidation of propylene). The reaction of allyl alcohol with hydrogen peroxide produces glycidol as an intermediate, which is further hydrolyzed to glycerol.
Manufacture of Glycerine from Petrochemical and Carbohydrate Raw Materials
Published in Eric Jungermann, Norman O.V. Sonntag, Glycerine, 2018
Propylene oxide was isomerized over a lithium phosphate catalyst deposited on an inert support to allyl alcohol. The isomerization occurs at 280°C and a space velocity of 1600 reciprocal hours. Yield of allyl alcohol is 94–98% at a conversion of 20–30% per pass. Allyl alcohol, was epoxidized in aqueous media to glycidol with peracetic acid [French patents 1,501,277–8 (1/12/68) (aqueous epoxldations) although FMC Corp. has an alternate solvent epoxidation route U.S. patent 3,954,815 (5/4/76)] and this hydrolyzed to glycerol with aqueous formic acid [U.S. patent 1,509,277 (1/12/68)]. An alternative route involving chlorlnation of allyl alcohol to glycerol dichloro-hydrins by liquid phase chlorination and thence to epichlorohydrin and glycerol, as practiced by Shell and Dow, was apparently considered uneconomical by FMC Corp.
A review on solid base heterogeneous catalysts: preparation, characterization and applications
Published in Chemical Engineering Communications, 2022
Diksha K. Jambhulkar, Rajendra P. Ugwekar, Bharat A. Bhanvase, Divya P. Barai
For the transesterification of glycerol and urea or alkyl carbonates like dimethyl carbonate (DMC) and diethyl carbonate (DEC), solid base catalyst was found to be more favorable then solid acid catalysts because of high product formation (Liu et al. 2013). In chemical industries, glycerol carbonate (GC) is the most promising material due to its biodegradability, non-hazardous and non-flammable nature (Wang et al. 2011). Also, it is one of the high-boiling, lower vapor pressure liquids. GC is reported as significant component in coatings, paints, detergents, lithium ion batteries, gas separation membranes, polyurethane foams and can be used as electrolyte. Also, a value-added compound glycidol, which is a derivative of GC, is used as a source for polymeric materials in order to produce several polymers such as polyurethanes, polyesters, polyamides, and polycarbonates along with surfactants and lubricating oils employed in plastics, textiles, cosmetics, and pharmaceutical industries. The reaction mechanism for the transesterification between glycerol and DMC using base catalyst (B) is described in Figure 26 (Ochoa-Gómez et al. 2009). In the first step, glycerol and base catalyst reacted to give glyceroxide anion and base conjugated acid (BH). In the second step, glyceroxide anion reacted with dimethyl carbonate to form methyl glyceryl carbonate intermediate complex and methoxide anion. This methoxide anion interacted with the previously formed conjugated acid of the base (BH) to produce methanol and the base catalyst was thus regenerated. In the final step, the intermediate complex methyl glyceryl carbonate underwent intramolecular attack of hydroxyl oxygen on the carbonyl carbon resulting in formation of glycerol carbonate and methanol (Ochoa-Gómez et al. 2009; Simanjuntak et al. 2011). Details of esterification of glycerol carried out by various researchers in the past using different solid base catalysts are listed in Table 5.