Papers by Author: Bing Nan Ren

Abstract: The metal oxide catalyst was prepared by loading Mn_xO_y on carbon nanotubes (CNTs) with impregnation method. Then the catalyst was characterized by BET, TEM and XPS, and the catalytic activity of the catalyst for selective catalytic reduction (SCR) of NO at low-temperature was investigated. The results showed that the species of active components loaded on the catalyst were MnO₂ and Mn₂O₃. The NO conversion was improved with reduction temperature increase under 250°C, increased slowly over 250°C. The O₂ content had an outstanding effect on NO conversion of catalysts at a low concentration range. Once the oxygen content was enhanced over 5%, there was no significant increase in the NO conversion. With the increasing of space velocity, the NO conversion rate was decreased under the reaction conditions.

Abstract: The optimal preparation condition of V2O5/TiO2 catalyst was investigated by the orthogonal experimental method. Five factors were chosen including A(molar ratio of NH4VO3 to oxalic acid),B(aging time of solution),C(active component content),D(impregnation temperature) and E(impregnation time). Every factor had four levels. The levels of A were1:2, 1:1, 3:2 and 2:1. The levels of B were 12h, 14h, 16h and 18h. The levels of C were 2%, 4%, 6% and 8%. The levels of D were 45°C, 55°C, 65°C, 75°C. The levels of E were 2h, 3h, 4h and 5h.The orthogonal experiment table was L16(45). Then the de-NOx rate of V2O5/TiO2 catalysts was tested in SCR catalytic reactor. The results showed that the influence of chosen factors decreased in the following order: C> B> E> D> A. The optimal plan of preparation experiments, obtained from the orthogonal experiment, is C3B1E3D3A4. So the optimal condition of preparation experiments are that active component content is 6%，aging time of solution is 12h，impregnation time is 4h，impregnation temperature is 65°C，molar ratio of ammonium metavanadate and oxalic acid is 2:1.

Abstract: Carbon materials have a very large surface area and various surface functional groups. They have been widely used as the adsorbent alone or the modified surface to adsorb pollutants. In the process of producing of yellow phosphorus by electric furnace, about 3000 m3 tail gas will be let out for one ton yellow phosphorus production. Tail gases consist of 90% of carbon monoxide (CO) and phosphine (PH3). The PH3 prevents the highly efficient utilization of CO and is an irritant and general systemic poison. Therefore, it is necessary to study how to effectively remove PH3 in tail gases. Due to the fact that selective adsorption of non-modified activated carbon (AC) is not enough to remove PH3 with a high efficiency, modification of AC might be an attractive route to improve the adsorption capacity. In this paper, experiments were carried out to study the factors influencing the adsorption of PH3 on the modified AC such as the concentration of impregnant, reaction temperature, oxygen content and space velocity. The results showed that the 5% HCl was the optimum concentration of impregnant. In the presence of oxygen, the adsorption capacity of modified AC was more than that in the absence of oxygen. In addition, with the improvement of the reaction temperature, the adsorption capacity of modified AC was increasing initially then decreasing, because of the transition from physical adsorption to chemical adsorption as priority. The adsorption capacity of the modified AC was enhanced initially with the increasing of oxygen content. Once the oxygen content was enhanced over 1%, there was no significant increase in the adsorption capacity of modified AC. The adsorption capacity of modified AC was decreased with the increasing of space velocity. The optimum parameters of reaction were 5% HCl of impregnant, 70°C of reaction temperature, 1% of oxygen content, and space velocity 10～20min-1.