Lipase Catalyzed Synthesis of Medium-chain Biodiesel from Cinnamonum camphora Seed Oil

The non-edible camphor tree seed oil was extracted and catalyzed by immobilized lipase for biodiesel production. The oil yield from camphor tree seeds reached 35.2% of seed weight by twice microwave-assisted extractions. Gas chromatography showed that free fatty acid content in camphor tree seed oil was 1.88%, and the main fatty acids were capric acid(53.4%) and lauric acid(38.7%). With immobilized lipase Candida sp. 99–125as catalyst, several important factors for reaction conditions were examined through orthogonal experiments.The optimum conditions were obtained: water content and enzyme loading were both 15% with a molar ratio of 1:3.5(oil/ethanol), and the process of alcoholysis was in nine steps at 40 °C for 24 h, with agitation at170 r·min-1. As a result, the medium-chain biodiesel yield was 93.5%. The immobilized lipase was stable when it was used repeatedly for 210 h.

Supercritical Synthesis of Ethyl Esters via Transesterification from Waste Cooking Oil Using a Co-Solvent

Biofuels became more promising alternative to the fossil fuels because of the depletion of fossil resources, renewability, environmental benefits, and energy security. Ethanolysis of waste cooking oil with hexane as co-solvent was carried out for the production of fatty acid ethyl ester (FAEE). This process reduced the severity of process parameters with high purity biodiesel yield. Process variables such as co-solvent ratio, ethanol to oil molar ratio, reaction temperature and reaction time were optimized. The maximum biodiesel yield of 88% was obtained at ethanol/oil molar ratio of 40:1, co-solvent (hexane) to oil ratio of 0.2% (v/v), reaction temperature of 300°C in 20 min of reaction time. Fatty acid ethyl ester (biodiesel) samples produced from this process were measured and evaluated using GC-MS analytical instrument. Thermo gravimetric analysis (TGA) was also performed to examine the thermal stability of waste cooking oil, ethyl esters and fuel blends. Fuel properties of ethyl esters were determined and compared with the ASTM standards for biodiesel, regular diesel and ethyl esters from different feedstock.

Facile preparation of coal-based ultramicroporous carbon microspheres for selective CO_(2)capture

The basic structure of aromatic compounds that are abundant in coal is the carbonaceous precursor derived from carbon microspheres.However,it remains to be a huge challenge to prepare carbon microspheres using coal due to the complex construction and composition of coal.Herein,a simple and viable way to obtain coal-based microporous carbon microspheres was developed by means of ethanol pyrolysis and a sequential extraction strategy.The as-prepared carbon microsphere featured aspherical micron particles of a uniform size(0.6-1.6㎛),abundant O-functional groups,excellent thermal stability,high SBET(415.5-983.2 m^(2)/g),and plentiful ultra-micropores(63.15-72.72%).The coal-based carbon microsphere exhibited a noteworthy CO_(2)uptake(3.19-4.97 mmol/g at 273 K and 1.0 bar),acceptable CO_(2)/N_(2)selectivity(IAST:23-46)and moderate isosteric heats(20-32 kJ/mol).This synthetic strategy is important for the preparation of ultramicroporous carbon microspheres using coal,and the synthetic carbon microspheres have promising prospects for highly efficient CO_(2)capture.