جستجوی مقالات مرتبط با کلیدواژه « ترانس استری شدن » در نشریات گروه « شیمی »

Today, biodiesel is being produced and consumed around the world as one of the main sources for replacing fossil fuels. In current research, cobalt doped zinc oxide was used as nanocatalyst to produce biodiesel from soybean oil by transesterification reaction. The nanocatalysts used were first prepared by microwave method and identified by X-ray diffraction (XRD), scanning electron microscopy (SEM) and x-ray energy dispersive spectroscopy (EDS). In the next step, the prepared catalysts were used in the reaction of biodiesel production from soybean oil. The produced biodiesel was characterized using nuclear magnetic resonance spectroscopy (NMR) and gas chromatography-mass spectroscopy (GC-MS). Optimal reaction conditions of biodiesel production with cobalt doped zinc oxide nanocatalyst obtained, at 3 h, temperature 60 ˚C, catalyst concentration 3% by weight, and molar ratio of oil to methanol 1 to 41 resulted in 98% efficiency. In another part of this research, microwave radiation with a power of 250 W was used as a source of energy in the biodiesel production reaction which in the presence of 4% by weight of catalyst and molar ratio of oil to methanol 1 to 20 resulted in 91% efficiency in 180 s.

MCM-41 mesoporous material were synthesized non-hydrothermally and magnesium and calcium ions were incorporated in MCM-41 framework by two approaches; Wet Impregnation (WI) and Template Ion Exchange (TIE). For comparison, magnesium containing MCM-41 was also synthesized. The prepared catalysts were characterized by powder X-ray diffraction (XRD) and infrared spectroscopy (FT-IR). The results displayed the ordered structure of MCM-41 mesopore was preserved after metal incorporation. The amount of calcium and magnesium were determined using energy-dispersive X-ray spectrometer (EDX). The catalysts were tested for biodiesel production from canola oil with methanol at 70° C. The effect of the residual template within the pores on catalysts activity was also investigated .Template-containing Mg-Ca/MCM-41 prepared by TIE method, showed the best catalytic performance in transesterification of canola oil after 6 hours (88.6%). Since there is no need to remove organic template, then this catalyst saves energy and time and it also reduces the pollutants released to the environment.