Title:Can Glycerol Carbonate be Synthesized Without a Catalyst?
Volume: 21
Issue: 7
Author(s): Sanjib Kumar Karmee*
Affiliation:
- The Odisha Renewable Energy Research Institute (ORERI), Subarnapur, Odisha, 767018, India
Keywords:
Glycerol, microwave, transesterification, glycerol carbonate, green chemistry, dimethyl carbonate.
Abstract: Biodiesel and oleo-chemical industries have been producing huge quantities of glycerol as
a by-product. Value-added products can be synthesized from glycerol through different chemical and
enzymatic reactions, such as oxidation, carbonylation, reforming, acetalyzation, etherification, dehydration,
hydrogenolysis, hydrolysis, esterification, and transesterification. Glycerol is a low-cost polyol
that can be converted into glycerol carbonate, which has potential applications in polymer and biobased
non-isocyanate polyurethanes industries (Bio-NIPUs). The present contribution is the first of its
kind to report on the synthesis of glycerol carbonate via catalyst and solvent-free transesterification of
glycerol with dimethyl carbonate under conventional as well as microwave heating. Additionally, a
comparative study of conventional and microwave-assisted transesterification was performed. Under
conventional heating, 78% glycerol carbonate is obtained at 120oC in 36 hours, whereas, using microwaves,
92% of glycerol carbonate can be achieved in 30 minutes. Presently, biomass-based heterogeneous
materials are used in catalysis due to their importance within the context of sustainability. In
line with this, in this work, a series of green catalysts, namely, molecular sieves (MS, 4Å), Hβ-
Zeolite, Montmorillonite K-10 clay, activated carbon prepared from the shell of groundnut (Arachis
hypogaea), and biochar from sawdust pyrolysis were successfully employed. Glycerol carbonate was
thoroughly characterized by 1H and 13C NMR, FT-IR and MS. The method described here is facile
and green since the utilization of bioresource (glycerol) for the production of glycerol carbonate is
performed under microwave.