Renewable Energy Resources and Technologies
Sharareh Esmaeili; Kambiz Tahvildari; Barat Ghobadian; Masoud Dehghani-Soufi; Sanaz Mohammadzadeh Koumleh; Tirth Panchal
Abstract
The presence of increasing concerns and enforcement of growing regulations over environmental pollution are nowadays at play. The pollution arising from mineral oils is among the major concerns. With the gradual reducation of the world oil reserves, an increasing pressure comes into play for finding ...
Read More
The presence of increasing concerns and enforcement of growing regulations over environmental pollution are nowadays at play. The pollution arising from mineral oils is among the major concerns. With the gradual reducation of the world oil reserves, an increasing pressure comes into play for finding sustainable alternatives. Being appealing alternatives, vegetable oils consist of different fatty acids; however, they cannot be applied directly to internal combustion engines owing to their poor oxidation stability and high pour point value. Biolubricants are considered to be a new generation of lubricants, which are renewable and biodegradable and are produced from the chemical modification of vegetable oils. There are few studies investigating the feasibility of using the mixture of fatty acids as biolubricant feedstock. In this study, epoxidation, oxirane ring opening with palmitic acid and p-Toluenesulfonic acid, esterification reaction with octanol, and reaction of the remaining hydroxyl group with stearic acid were applied to modify the mixture of oleic and linoleic fatty acids and produce biolubricant. For this purpose, the IR spectrums of each epoxide, monoester, diester, and triester products were obtained and analyzed. At the end of the experiments, monoester, diester, and triester were obtained with 94 % yield, with 96 % yield, and with 98 % yield, respectively. Eventually, the final product was found with physicochemical properties comparable with the physicochemical properties of the lubricant standard ISO VG10.
Renewable Energy Resources and Technologies
Tazkieh Gilvari; Behzad Aghabarari; Mohammad Pazouki
Abstract
This study investigated the esterification reaction of different carboxylic acids (Acetic acid, Palmitic acid, and Oleic acid) and ethanol by ZnO, Al2O3-ZnOmixed oxide, and phosphotungestic acid (10 wt %) immobilized on the Al2O3-ZnOmixed oxide. The heterogeneous catalysts were characterized by XRD, ...
Read More
This study investigated the esterification reaction of different carboxylic acids (Acetic acid, Palmitic acid, and Oleic acid) and ethanol by ZnO, Al2O3-ZnOmixed oxide, and phosphotungestic acid (10 wt %) immobilized on the Al2O3-ZnOmixed oxide. The heterogeneous catalysts were characterized by XRD, BET, FE-SEM, and EDX techniques. Optimum yield was achieved by using 10 % HPW/Al2O3-ZnOas the best catalyst, and the effects of the amount of catalyst, molar ratio of acid to alcohol, reaction temperature, and time were investigated to ensure the ideal yield of esterification reaction of acetic acid and ethanol. The results showed that the esterification of acetic acid to its ethyl ester was carried out in 3.5 hours, with an alcohol-to-acid-molar ratio of 2 and a temperature of 80 ˚C with yield 98 %. Moreover, the 10 % HPW/Al2O3-ZnOcatalystshowed well activity in biodiesel production by the esterification of palmitic and oleic acids and the reaction yield did not decrease with an increase in alkyl chain lengthin acid molecules, remarkably.