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In this work, an efficient and green glycerolysis reaction catalyzed by zinc glycerolate was developed to prepare biodiesel from oleic acid. The active phase of zinc glycerolate was investigated by XRD, FTIR, 1H NMR, and 13C NMR. An interesting result was obtained that zinc glycerolate was first dissolved to form zinc oleate and then regenerated to zinc glycerolate during the reaction, which was essential for the conversion of oleic acid. The relationship between dissolved zinc glycerolate and conversion of oleic acid was determined. The regeneration of zinc glycerolate was achieved when the molar ratio of glycerol to oleic acid was higher than 0.6:1. A plausible pathway for the glycerolysis reaction catalyzed by zinc glycerolate was proposed. Zinc glycerolate could be recycled 10 times with no obvious decrease in catalytic activity, and the oleic acid conversion of 98% was achieved. In addition, zinc glycerolate was applied to catalyze glycerolysis reaction of different feedstock and demonstrated excellent performance. The results show that zinc glycerolate is a promising catalyst in glycerolysis reaction for biodiesel production. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel microwave-assisted system is developed for acrolein hydration to 3-HPA. • Simultaneous cooling is adopted for continuous microwaves and stable temperature. • Kinetic study indicates reduction in activation energy under microwave irradiation. • Adsorption and reaction behavior of reactants on catalyst is theoretically studied. • The DFT calculations confirm the intensification effect of microwave field. Catalytic hydration of acrolein to 3-hydroxypropionaldehyde (3-HPA) is a key step for the chemical production of 1,3-propanediol (1,3-PDO) from renewable glycerol. However, a main issue of low reaction rate and long reaction time exists in the conventional hydration process. Here, we developed a microwave-assisted system for the efficient conversion of acrolein to 3-HPA. Simultaneous cooling method was adopted to maintain continuous microwave irradiation and meanwhile stable temperature during the reaction. The effects of catalyst type, temperature, catalyst loading and microwave power on acrolein conversion and 3-HPA selectivity were examined. Kinetic study showed that microwave irradiation could help for the reduction in activation energy, which led to acceleration in reaction rate during the acrolein hydration process. In addition, the density functional theory (DFT) calculations on the adsorption and reaction behavior of reactants molecules on the catalyst are consistent with the experimental results, which confirm the intensification effect of the microwave field. [ABSTRACT FROM AUTHOR]

Trimethylolpropane fatty acid triester (TFATE) is a promising biolubricant as an environmentally friendly substitute to conventional mineral-based lubricants. However, the issues of extensive energy consumption from vacuum maintenance and feedstock saponification caused by strong alkaline catalysts exist in current TFATE-based biolubricant synthesis. Here, sustainable production of biolubricant was achieved with methyl oleate (MO) from non-edible oil sources as the feedstock and moderate alkaline K 2 CO 3 as the catalyst. Nitrogen gas stripping method instead of vacuum was adopted for methanol removal. The effects of agitation speed, N 2 flow rate, catalyst amount, MO to trimethylolpropane (TMP) molar ratio and temperature on MO conversion and TFATE selectivity were examined. The TFATE selectivity reached 95.6% under the optimized conditions. Leaching tests indicated neglectable K 2 CO 3 dissolution in reaction products. The kinetic parameters for the three consecutive transesterification reactions were calculated. In addition, the synthesized biolubricants exhibit low acid value and volatility, moderate iodine value, superior thermal stability, and good rheological and frictional properties. [Display omitted] • Biolubricant TFATE was produced by methyl oleate transesterification over K 2 CO 3 catalyst. • Nitrogen gas stripping method instead of vacuum was adopted for methanol removal. • The TFATE selectivity reached 95.6% under the optimized conditions. • Kinetic parameters for three consecutive transesterification reactions were calculated. • Products show superior thermal stability and good rheological and frictional properties. [ABSTRACT FROM AUTHOR]

Undecylenic acid methyl ester (UAME) was continuously produced from methyl ricinoleate using a microwave-assisted pyrolysis system with atomization feeding. The UAME yield of 77 wt.% was obtained at 500 °C using SiC as the microwave absorbent and heating medium. The methyl ricinoleate conversion and UAME yield from microwave-assisted pyrolysis process were higher than those from conventional pyrolysis. The effect of temperature on the pyrolysis process was also investigated. The methyl ricinoleate conversion increased but the cracking liquid yield decreased when the temperature increased from 460 °C to 560 °C. The maximum UAME yield was obtained at the temperature of 500 °C. [ABSTRACT FROM AUTHOR]