The mechanism of all present adopted desulfurization technologies is chemical reaction. A new kind of desulfurization medium - TiO 2 particle having large fraction void and specific surface area which is made from Ti...The mechanism of all present adopted desulfurization technologies is chemical reaction. A new kind of desulfurization medium - TiO 2 particle having large fraction void and specific surface area which is made from TiO 2 with superfine size sintered at low temperature and processed with surface activation is tested and investigated. The mechanism of desulfurization is mainly physical adsorption instead of traditional chemical reaction. Four samples of such TiO 2 particles were characterized by advanced instruments and tested for adsorption dynamics at the temperature range of 90?℃ to 240?℃ in a fixed bed. The results show that its adsorption ability for SO 2in flue gas is dependent strongly on three factors: quality of TiO 2particles, adsorption temperature and SO 2 concentration in flue gas. Titanium dioxide has well desulfurization character and pretty good prospect in engineering application. Sintered at temperature range from 440?℃ to 540?℃, it has the best adsorption ability. In practical use the best adsorption temperature is around 120?℃.展开更多
Pt is a catalyst in proton exchange membrane fuel cell （PEMFC）, and its activity will be degraded in the air due to the exist- ence of SOx impurities. On strategy is introducing of Mo into the Pt catalyst because it...Pt is a catalyst in proton exchange membrane fuel cell （PEMFC）, and its activity will be degraded in the air due to the exist- ence of SOx impurities. On strategy is introducing of Mo into the Pt catalyst because it can improve the SOx-tolerance capacity. Based on the aforementioned phenomenon, a density function theory （DFT） study on SOx adsorbed on Pt（111） and PtMo（111） was performed to enhance Pt catalytic activity. The adsorption energy of adsorbed species, the net change, partial density of state （PDOS）, and d-band center were calculated and analyzed comparatively. The results show that the presence of Mo-atom weakens the S-Pt bond strength and reduces the adsorption energies for SO2, S and SO3 on PtMo（111）. Moreover, the Mo atom weakens the effects of SO2 on the PtMo（lll） electronic structure and makes the catalyst maintains its original electronic structure after SO2 adsorption as compared with Pt（111）.展开更多
文摘The mechanism of all present adopted desulfurization technologies is chemical reaction. A new kind of desulfurization medium - TiO 2 particle having large fraction void and specific surface area which is made from TiO 2 with superfine size sintered at low temperature and processed with surface activation is tested and investigated. The mechanism of desulfurization is mainly physical adsorption instead of traditional chemical reaction. Four samples of such TiO 2 particles were characterized by advanced instruments and tested for adsorption dynamics at the temperature range of 90?℃ to 240?℃ in a fixed bed. The results show that its adsorption ability for SO 2in flue gas is dependent strongly on three factors: quality of TiO 2particles, adsorption temperature and SO 2 concentration in flue gas. Titanium dioxide has well desulfurization character and pretty good prospect in engineering application. Sintered at temperature range from 440?℃ to 540?℃, it has the best adsorption ability. In practical use the best adsorption temperature is around 120?℃.
基金financially supported by the National Basic Research Program of China (973 Program, 2012CB215500, 2012CB720300)the National Natural Science Foundation of China (51072239, 20936008)the Fundamental Research Funds for the Central Universities (CDJZR-12228802)
文摘Pt is a catalyst in proton exchange membrane fuel cell （PEMFC）, and its activity will be degraded in the air due to the exist- ence of SOx impurities. On strategy is introducing of Mo into the Pt catalyst because it can improve the SOx-tolerance capacity. Based on the aforementioned phenomenon, a density function theory （DFT） study on SOx adsorbed on Pt（111） and PtMo（111） was performed to enhance Pt catalytic activity. The adsorption energy of adsorbed species, the net change, partial density of state （PDOS）, and d-band center were calculated and analyzed comparatively. The results show that the presence of Mo-atom weakens the S-Pt bond strength and reduces the adsorption energies for SO2, S and SO3 on PtMo（111）. Moreover, the Mo atom weakens the effects of SO2 on the PtMo（lll） electronic structure and makes the catalyst maintains its original electronic structure after SO2 adsorption as compared with Pt（111）.
