Transesterification of soybean oil (SBO) and other triglycerides with alcohols, in the presence of a catalyst, yields fatty esters and glycerol. Di- and monoglycerides are intermediates. Reactions are consecutive and reversible. Rate constants have been determined for each reaction with a computerized kinetic program. The effects of the type of alcohol, 1-butanol or methanol (MeOH); molar ratio of alcohol to SBO; type and amount of catalyst; and reaction temperature on rate constants and kinetic order were examined. Forward reactions appear to be pseudo-first order or second order depending upon conditions used. Reverse reactions appear to be second order. At a molar ratio of MeOH/SBO of 6:1, a shunt reaction was observed. Energy of activation was determined for all forward and reverse reactions under a variety of experimental conditions from plots of log k vs 1/T. Values ranged from 8–20 kcal/mol.

Transesterification kinetics of soybean oil 1

The paper reviews the problem due to the use and disposal of synthetic polymers to the environment and its solutions; in particular poly (ethylene terphthalate). Wide spread application and non-biodegradability of the PET creates huge amounts of waste and disposal, tend to a serious problem. The most important cause for recycling and reprocessing the waste PET has arisen from the awareness and concern for environmental pollution. To manage this various methods of polymer recycling has been proposed. Among them chemical recycling, i.e. hydrolysis, methanolysis, glycolysis and aminolysis are reviewed in detail. Appropriate technology and waste disposal procedures based on the socio-economic aspect to solve this problem are suggested.

Pet Waste Management by Chemical Recycling: A Review

A review of the immobilization of enzymes in electropolymerized films

Cubic liquid crystalline phases are common in surfactant and surfactant-like lipid systems at temperatures above the Krafft point. They are optically isotropic and very stiff. Therefore, they are often not recognized as independent phases and separated in pure state. The liquid crystalline nature is evidenced by a low-angle diffraction pattern with sharp reflections having Bragg-values above 20 A coupled with a diffuse wide-angle reflection at 4.5 A, proving that the hydrocarbon moiety is in a liquid state. The cubic phases occur in a variety of lipid/water systems (also with liquid organic solvents), such as simple soaps, amphiphilic lipids of biological origin, and extracts from membrane lipids. The location of the cubic phases in a phase diagram varies. The original concept of a cubic structure composed of closed globular aggregates, either of “oil-in-water” or “water-in-oil” type in face-centered array seems to be obsolete. The present structure concepts include closed anisotropic aggregates, short rod-like aggregates forming continuous networks or lamellar aggregates with “zero” curvature forming networks of Infinite Periodic Minimal Surfaces (IPMS). The structure is mostly primitive or body-centered cubic.

Cubic phases in surfactant and surfactant-like lipid systems

Nowadays, most biodiesel (fatty acids methyl esters, FAME) is produced by the transesterification of triglycerides (TG) of refined/edible type oils using methanol and an homogeneous alkaline catalyst However, production costs are still rather high compared with the ones of petroleum-based diesel fuel To lower costs and make biodiesel competitive less-expensive feedstocks such as waste fats or non-edible type oils could be used The use of homogeneous alkaline catalysts in the transesterification of such types of fats and oils poses great difficulties due to the presence of large amounts of free fatty acids (FFA) This paper studies the use of carboxylic salts as a possible alternative, because these catalysts are active also in the presence of high FFA concentrations The most active catalyst (Cd, Mn, Pb, Zn carboxylic salts) have been individuated and a correlation of the activities with the cation acidity has been found

Synthesis of biodiesel via homogeneous Lewis acid catalyst

Studies on the formation of poly(ethylene terephthalate): 6. Catalytic activity of metal compounds in polycondensation of bis(2-hydroxyethyl) terephthalate

Studies on the formation of poly(ethylene terephthalate): 3. Catalytic activity of metal compounds in transesterification of dimethyl terephthalate with ethylene glycol

Studies on the formation of poly(ethylene terephthalate): 2. Rate of transesterification of dimethyl terephthalate with ethylene glycol

Studies on the formation of poly(ethylene terephthalate): 1. Propagation and degradation reactions in the polycondensation of bis(2-hydroxyethyl) terephthalate

Kosuke Tomita

Papers

Studies on the formation of poly(ethylene terephthalate): 6. Catalytic activity of metal compounds in polycondensation of bis(2-hydroxyethyl) terephthalate

Studies on the formation of poly(ethylene terephthalate): 3. Catalytic activity of metal compounds in transesterification of dimethyl terephthalate with ethylene glycol

Studies on the formation of poly(ethylene terephthalate): 2. Rate of transesterification of dimethyl terephthalate with ethylene glycol

Studies on the formation of poly(ethylene terephthalate): 1. Propagation and degradation reactions in the polycondensation of bis(2-hydroxyethyl) terephthalate

Electron transferase activity of diaphorase (NADH: acceptor oxidoreductase) from Bacillus stearothermophilus