Ultrasound assisted enzyme catalyzed synthesis of glycerol carbonate from glycerol and dimethyl carbonate

Abstract

The present work illustrates the transesterification of glycerol to glycerol carbonate (GlyC) from dimethyl carbonate (DMC) using commercial immobilized lipase (Novozym 435) under ultrasonic irradiation. The experiments were performed in a batch reactor placed in an ultrasonic water bath using a sequence of experimental protocol to evaluate the effects of temperature, molar ratios of substrates, enzyme loading, duty cycle and ultrasound power on the conversion of glycerol to GlyC. It has been found that ultrasound-assisted lipase-catalyzed transesterification of glycerol would be a potential alternative to conventional alkali-catalyzed method, as high conversion (99.75%) was obtained at mild operating conditions: molar ratio of DMC to glycerol 3:1, catalyst amount of 13% (w/w), lower power input (100W), duty cycle 50% and temperature (60°C) in a relatively short reaction time (4h) using Novozym 435 as catalyst. Ultrasound reduces the reaction time up to 4h as compared to conventional stirring method (14h) catalyzed by Novozym 435. The repeated use of the catalyst under the optimum experimental condition resulted in decay in both enzyme activity and product conversion.

Review on recent progress in catalytic carboxylation and acetylation of glycerol as a byproduct of biodiesel production

“…oxides [59], ionic liquids (ILs) [60], enzymes [61,62], hydrotalcites [63], and mixed metal oxides [49]. These catalysts, which are categorized as homogenous, heterogeneous, and enzyme catalysts, depending on their role and application in catalysis, have been utilized to synthesize GC with yields ranging from 50% to 98% [59,64].…”

Lipase-catalyzed ethanolysis of Jatropha curcas L. oil assisted by ultrasonication

“…Many interesting works using ultrasound to enhance biodiesel conversion with reaction catalyzed by enzymes are described in the literature (Waghmare et al, 2015;Lerin et al, 2014;Awadallak et al, 2013;Batistella et al, 2012;Fiametti et al, 2012;Kumar et al, 2011). However, we have not found reports that describe the ethanolysis of Jatropha curcas oil under ultrasound irradiation.…”

“…Recent developments in sonochemistry (Veljkovic et al, 2012;Deshmane et al, 2008) attracted great attention with the use of an ultrasound bath as a new, efficient mixing tool, based on emulsification of immiscible liquids (reactants) by microturbulence, which is generated by the implosion of cavitation bubbles (Andrade-Tacca et al, 2014;Gebicka and Gekicki, 1997). Hence, to overcome the drawbacks of the conventional stirring method, an ultrasound bath is considered to be green methodology due to its high efficiency and mild reaction conditions (Waghmare et al, 2015). Transesterification reactions depend on the basic parameters such as molar ratio, catalyst concentration, and reaction temperature.…”

Ionic Liquid–Silicotungstic Acid Composites as Efficient and Recyclable Catalysts for the Selective Esterification of Glycerol with Lauric Acid to Monolaurin

“…[1] Despite the fact that GL is ap romising low-cost raw material for the productions of food additives, surfactants, soap, medicines, and cosmetics, [2] itsu tilization towards more value-added chemicals remainsachallenging and demanding task. [3][4][5][6] On the other hand, glycerolm onolaurate( GML;a lso known as glyceryl laurateo rm onolaurin)h as been widely used as emulsifiers or an antibacteriala gent in the food, pharma-ceutical, and cosmetic industries. [7] GML is also one of the generally recognized as safe (GRAS) food additives certified by the US Federal Drug Administration (FDA) and is commonly synthesized by the direct esterification of GL with laurica cid (LA; or dodecanoic acid) over acidic catalysts.…”