Selective Oxidation of Crude Glycerol to Dihydroxyacetone in a Biphasic Photoreactor

Alexander Luis Imbault,Ramin Farnood

doi:10.3390/catal10040360

Alexander Luis Imbault, Ramin Farnood

Open Access

https://doi.org/10.3390/catal10040360

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Journal: Catalysts (Basel, Switzerland)	Publication Date: Mar 26, 2020
Citations: 4	License type: CC BY 4.0

Affiliation: University of Toronto

Abstract

In this paper, the first biphasic photoreactor was introduced and utilized for the conversion of glycerol to glyceraldehyde (GAD) and dihydroxyacetone (DHA) using water and ethyl acetate as dispersed (active) and continuous (inactive) phases, respectively. Increasing the ethyl acetate content in the reactor improved the DHA yield; however, the optimal DHA selectivity was obtained at an ethyl acetate to water ratio of 90:10 (vol/vol). Compared to a monophasic photoreactor containing only water and identical amounts of glycerol and photocatalyst, the biphasic reactor containing 90 vol % ethyl acetate increased the DHA yield by a factor of 2.9 (from 4.5% to 13%) and the concentration of DHA by approximately 14 times (from 0.08 mM to 1.1 mM) after 240 min. Additionally, photocatalytic conversion of crude glycerol extracted using a 90:10 (vol/vol) ethyl acetate-water mixture showed a similar DHA conversion and yield to that of pure glycerol.

Highlights

Crude glycerol is a low-value by-product that is generated at a rate of 10:1 by weight in biodiesel production process [1]
Crude glycerol is typically disposed of by burning; the steady increase in the global biodiesel demand has caused a significant oversupply of this material and has triggered the search for novel methods to valorize this renewable resource to fuels and chemicals [2,3]
In our previous mixture.work, we reported conversion of crude glycerol to DHA using acetonitrile as a solvent

Summary

Introduction

Crude glycerol is a low-value by-product that is generated at a rate of 10:1 by weight in biodiesel production process [1]. Crude glycerol is typically disposed of by burning; the steady increase in the global biodiesel demand has caused a significant oversupply of this material and has triggered the search for novel methods to valorize this renewable resource to fuels and chemicals [2,3]. The photoactivation of TiO2 generates reactive species in water, mainly superoxide ions (O2 – ) and hydroxyl radicals (OH ) which react further [8]. This has been used extensively to degrade hazardous compounds in water and air systems as well as generate valorized products [9,10]

Methods

Results

Conclusion