Production of ethanol by Zymomonas mobilis using partially purified glycerol

Abstract

Glycerol obtained as a by-product from oleo chemical industries was effectively utilized as a substrate for the production of several value-added bio products such as acetic acid, citric acid, DHA, ethanol, etc. It has several advantages over commercial substrates which includes low cost nutrients, as a good carbon and energy source for the microorganisms to grow with high product conversion rate. The product formation was lowered due to the copious impurities present in the crude glycerol sample. The impurities present in the crude glycerolwere removed by two stage purification process. Purification process helps to increases the initial concentration of glycerol from 10 % (v/v). The resulting partially purified glycerol when used as a substrate produces 33.44 % (v/v) of ethanol with 27 % (v/v) concentration after simple distillation using Zymomonas mobilisat pH 6 and temperature 36oC. The partially purified substrate and the product ethanol were validated by GC-MS and GC-FID.