Design of a Synthetic Zinc Oxide Catalyst over Nano-Alumina for Sulfur Removal by Air in a Batch Reactor

Abstract

Owing to the environmental regulations with respect to sulfur content and continuing challenges of finding a suitable catalyst of such impurity, a driving force for the development of more efficient technologies a deep research on new oxidative catalysts is considered an important issue in fuel quality improvement. Thus, the present study shows a novel percent of nano-catalyst with 18% zinc oxide (ZnO) of active component over nano-alumina that has not been reported in the public domain for sulfur removal from kerosene fuel by air (oxidative desulfurization (ODS) method). Where, such percent of the active component on the nano-alumina helps to add one or two atoms of oxygen to sulfur content in the kerosene. The nano-catalyst (ZnO/nano-alumina-particles composite) is prepared by precipitation of zinc oxide and loaded over nano-alumina in one-step. The activity of the prepared catalyst was tested utilizing ODS process of kerosene fuel by air in a batch reactor. A set of experiments were conducted with a wide range of operating conditions, where the reaction temperature was ranged from 150 to 190 ºC, the reaction time from 30 to 50 min and the catalyst weight from 0.4 to 1 g. The experimental results showed that the chemical nature of zinc oxides showed higher conversion (70.52%) at reaction temperature of 190 ºC, reaction time of 50 min, and 1 g catalyst weight used in the batch reactor. A kinetic model related to the sulfur removal from kerosene via ODS process in the batch reactor was also investigated in this study for the purpose of estimating the best kinetic parameters of the relevant reactions. The results showed that the prepared catalyst (ZnO over nanoalumina) can be applied confidently to reactor design, operation and control in addition to improve the fuel quality. Following the kinetic model of ODS process, a very well agreement between the experimental and predicted results is obtained. lations were reported that the maximum sulfur content should not be currently exceeded 0.005 wt%, and less than 0.0015 wt% or nil (freesulfur content) in the coming years [2][3][4]. The main source of air pollution is attributed to the generation of sulfur oxides by the combustion process leading to form acid rain. The oxidation desulfurization process used for removal all types of sulfur in fuel is expected to solve great environmental problems occurring wherever different petroleum fractions are used [5]. The

ZnO-Activated Carbon Blended as a Catalyst for Oxidative Desulfurization of Dibenzothiophene

“…Another study stated that the increment of the catalytic activity of ZnO can be corresponded to a lower band gap value (3.35 eV) compared to 3.65 eV for Zn5(OH)8Cl2•H2O, which would increase the absorption capacity of higher wavelength radiation [10]. A novel percent of nano-catalyst with 18% zinc oxide (ZnO) was an active component over nano-alumina for sulfur removal from kerosene fuel by air (oxidative desulfurization (ODS) method) [11]. Riad and Mikhail showed that Zn-incorporated hydroxyapatite catalysts were investigated towards oxidative desulfurization of light gas oil with a total sulfur content of 1281.8 ppm.…”

Modeling, Evaluating and Scaling up a Commercial Multilayer Claus Converter Based on Bench Scale Experiments

“…H2S (hydrogen sulfide) and carbon-sulfur components (such as CS2 and COS) are toxic byproducts of refining natural gas and crude oil, and therefore, their entrance in any exhaust gas is under stiff environmental regulations [1,2]. To tackle with this issue, the modified sulfur re-covery unit (SRU) is cherished to convert H2S and carbon-sulfur compounds coming from the exhaust of those industries to the elemental sulfur [3,4].…”

“…The modified Claus process is conducted at two steps including thermal and catalytic stages [5]. The catalytic reactors of a SRU is usually loaded by alumina (Al2O3) and titania (TiO2) Claus catalysts (combined bed or multilayer configuration) to promote the following reactions [6,7]: Copyright © 2020, BCREC, ISSN 1978-2993 (1) (2) (3) Industrial scale reactors usually work adiabatically, and they are essentially different from bench or even pilot scale reactors. In the former, there is a temperature profile along the catalytic bed whereas in the latter a constant temperature governs the whole bed.…”

A Novel Synthetic Nano-Catalyst (Ag2O3/Zeolite) for High Quality of Light Naphtha by Batch Oxidative Desulfurization Reactor

“…A number of oxidants are used in the ODS that have been employed for the selective oxidation of sulfur compounds in oil feedstock [14][15][16][17]. In order to improve the efficiency of sulfur removal in the ODS via using air as an oxidant, various catalysts have been evaluated including Al2O3-zeolite [18], Nano-Fe3O4 [19], -MnO2 (Nano sheets) [20], alumina [21], carbon Nano tube [20] and silica gel [19] found to enhance the desulfurization efficiency of the ODS process.…”

“…A large quantity of sulfur compound are enhanced by the use of an oxidizing agent compared with traditional agent (hydrogen peroxide) [21]. The oxidative desulfurization process has been applied by [4] for sulfur compounds presented in naphtha feedstock using 0.1 wt% of palladium/functionalized MWNTs prepared by impregnation method.…”