Rudolph Diesel Meets the Soybean: "Greasing" the Wheels of Chemical Education

Abstract

The use of vegetable oils for engine fuels may seem insignificant today. But such oils may become in the course of time as important as the petroleum and coal tar products of the present time.

Ultrasonic-Assisted Transesterification: A Green Miniscale Organic Laboratory Experiment

“…For most of reported transesterification reactions in instructional laboratories, − the reaction mixture usually needs to be heated and refluxed for 30 min or longer with heating, which can cause potential risks of fires, explosions, and heat burns. Microwave is another alternative heating source, which uses an expensive microwave reactor .…”

“…The reaction mixture after transesterification reaction usually needs to be placed undisturbed for a few hours to several days or directly use acid to wash the reaction mixture in instructional laboratories, − but it is difficult for students to observe the separation of products from the reaction mixture within a scheduled lab class. Using ultrasonic-assisted synthetic method yields already separated solutions (Figure ).…”

“…Biodiesel, fatty acids methyl esters (FAMES), is a better fuel in terms of engine performance, emissions reduction, lubricity, and environmental benefits as well as its availability from renewable resources, such as refined and waste vegetable oils and fats. − Biodiesel can be produced by transesterification of vegetable oils with short-chain alcohols in the presence of acid or base catalysts, which has been developed into hands-on laboratory experiments for high school and undergraduate chemistry laboratory as a valuable pedagogical approach for integrating sustainability, green chemistry, and organic chemistry. − In secondary and tertiary instructional laboratories, most biodiesel syntheses use heating with the exception of a single lab reporting the use of a microwave reactor . However, to the best of our knowledge, the ultrasonic-assisted synthesis of biodiesel in instructional chemistry laboratories has yet to be reported.…”

Qualitative and Quantitative Assessment of Biodiesel Derived from Microalgae

“…As an emerging renewable fuel, biodiesel is an engaging teaching topic, with several activities − and laboratory teaching experiments utilizing a variety of feedstocks, like commercially available petroleum diesel and biodiesel, − fresh and waste cooking oils, − and nonfood crops and waste biomass. − To the best of the authors’ knowledge, only one experiment uses a microalgae feedstock, where over a semester students gain valuable insight into the production cycle of biodiesel. From a teaching viewpoint, the inclusion of biomass cultivation in limited class times is a logistical challenge.…”

Glicerol: um breve histórico e aplicação em sínteses estereosseletivas

“…Este produto é um combustível alternativo limpo, produzido pela reação de um óleo ou gordura com um álcool que reduz a viscosidade. 1,2 Nessa reação, chamada de transesterificação, são formados ésteres metílicos ou etílicos de ácidos graxos (biodiesel) e glicerol. Teoricamente, para cada 3 mols de ésteres metílicos (ou etílico) é gerado 1 mol de glicerol; aproximadamente 10% da massa total do produto.…”