Exxon Mobil and Their Move to Cellulosic Biodiesel

by Maithili Joshi

Exxon Mobil has made continuous efforts to look for alternative energy sources in the past few years. Recently, in the last four years, they had invested more than $100 million in developing algae-derived biofuels, and recently have refocused their efforts on researching the production of biodiesel by fermenting renewable cellulosic sugars from sources like agricultural waste. Exxon Mobil has teamed up with Renewable Energy Group (REG) and other universities to find a new source of renewable fuels, focusing on using sugars from non-food sources. Continue reading

Biofuel from Waste Pig Carcasses

by Emil Morhardt

Disposal of waste animal carcasses is expensive, a nuisance, and more trouble than its worth, at least some of the time in China. Consider that in 2013 over 16,000 dead pigs were dumped into one of Shanghai’s primary drinking water sources (Zhang and Ji, 2024). If this waste product were more valuable, than nothing of the sort would happen. According to these authors the carcasses are, in fact, worth $56/tonne, when converted to biofuel. To prove their point, they used pig carcasses to make biodiesel and biogas. They cooked them in water in an autoclave (basically a pressure cooker) for six hours then extracted the pig fat from the water and converted it to biodiesel. The remaining water was inoculated with anaerobic bacteria from a pig farm digester, and allowed to form biogas, in this case 63% methanol. Continue reading