Sina Rashidi; Mohammad Reza Khosravi Nikou; Bagher Anvaripour; Touba Hamoule
Abstract
The performance of MSU-S and its forms modified with phosphotungstic acid (HPW) and nickel (Ni) for the desulfurization and denitrogenation of model diesel fuel were studied. According to the results of the characteristic tests (N2 adsorption-desorption, XRD, SEM, and NH3-TPD), heteropoly acid incorporation ...
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The performance of MSU-S and its forms modified with phosphotungstic acid (HPW) and nickel (Ni) for the desulfurization and denitrogenation of model diesel fuel were studied. According to the results of the characteristic tests (N2 adsorption-desorption, XRD, SEM, and NH3-TPD), heteropoly acid incorporation causes higher acidity along with a negligible loss of structural aspects, while Ni impregnation leaves a drastic negative effect on mesoporous structure, crystalline phase, and particle shape along with a positive impact on surface acidity. With both modifications (HPW and Ni), the maximum increase of 33.18% and 6.88% was occurred for the adsorption loading of total sulfur and total nitrogen respectively. The adsorption loading and selectivity of all the adsorbents for total nitrogen were slightly more than those for total sulfur (the selective adsorption of nitrogen over sulfur). The pseudo-second order model can best fit the kinetics data and Freundlich model can best describe the equilibrium isotherm for all the species over Ni/HPW-MSU-S.
Hamed Rashidi; Touba Hamoule; Mohammad Reza Khosravi Nikou; Ahmad Shariati
Abstract
MSU-S mesoporous catalyst with [SiO2]/[Al2O3] ratio of 55 was synthesized using tetrapropylammonium hydroxide (TPAOH) as a structure directing agent and hexadecyltrimethylammonium bromide (CTAB) as a surfactant. The catalytic activity of the calcined sample was evaluated for the dehydration of methanol ...
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MSU-S mesoporous catalyst with [SiO2]/[Al2O3] ratio of 55 was synthesized using tetrapropylammonium hydroxide (TPAOH) as a structure directing agent and hexadecyltrimethylammonium bromide (CTAB) as a surfactant. The catalytic activity of the calcined sample was evaluated for the dehydration of methanol to dimethyl ether (DME) in a vertical fixed bed microreactor at a weight hurly space velocity (WHSV) of 5 hr-1 .Temperature ranged from 230 °C to 380 °C and pressure was kept constant at 1 bar. The catalyst was characterized by XRD; consequently, the mesoporous structure of MSU-S catalyst was verified. The activity, selectivity, and stability of MSU-S catalyst were investigated in a vertical fixed bed reactor. An increase in methanol conversion was observed by increasing temperature. The equilibrium conversion of methanol was almost reached at 380 °C and selectivity decreased from 100% to 97% as temperature rose from 200 °C to 380 °C. The stability of MSU-S (Michigan State University) catalyst was investigated for 12 hr at 380 °C and a stable methanol conversion was observed during the mentioned time.
