A Ni/TiO2（TBT） catalyst was prepared through in situ precipitation, using tetrabutyl titanate（TBT） as the TiO2 precursor, and was studied in CO methanation. A Ni catalyst supported on conunercial TiO2 was also pre...A Ni/TiO2（TBT） catalyst was prepared through in situ precipitation, using tetrabutyl titanate（TBT） as the TiO2 precursor, and was studied in CO methanation. A Ni catalyst supported on conunercial TiO2 was also prepared through post precipitation and studied to compare the influence of Ni precipitation conditions on the catalyst＇s performance. To gain insight on their structure and physicochemical properties, the catalysts were characterized with N2-adsorption, X-ray diffraction, transimission electron microscopy, H2 temperature programmed reduction and temperatttre programmed desorption. The results showed that the in situ precipitation method was beneficial to the dispersion of Ni and the formation of more active sites on the Ni/TiO2 catalyst. In addition, the density of the metal- support boundary and its interaction with the active component were also increased. These characteristics of Ni/TiO2（TBT） led to a lower light-off temperature and a suppression of Ni sintering during CO methanation. As a consequence, the Ni/TiO2（TBT） exhibited better catalytic behavior, with a CO conversion of 99.4% and CH4 selectivity of 90.4% tinder the following conditions： p=1 MPa, t=320℃, n（H2）/n（CO）=3, gas hour space velocity （GHSV）=2×10^4 mL·g^-1·h^-1. The life test results of the two catalysts showed that Ni/TiO2（TBT） was more stable and the catalytic activity remained at its initial level after being used for 30 h.展开更多
基金Supported by the National Natural Science Foundation of China（No. 51661145011）, the National Science and Technology Supporting Plan, China（No.2015BAD 15B06）, the Foundation of the State Key Laboratory of Clean Energy Utilization, China（No. ZJUCEU2016001 ）.
文摘A Ni/TiO2（TBT） catalyst was prepared through in situ precipitation, using tetrabutyl titanate（TBT） as the TiO2 precursor, and was studied in CO methanation. A Ni catalyst supported on conunercial TiO2 was also prepared through post precipitation and studied to compare the influence of Ni precipitation conditions on the catalyst＇s performance. To gain insight on their structure and physicochemical properties, the catalysts were characterized with N2-adsorption, X-ray diffraction, transimission electron microscopy, H2 temperature programmed reduction and temperatttre programmed desorption. The results showed that the in situ precipitation method was beneficial to the dispersion of Ni and the formation of more active sites on the Ni/TiO2 catalyst. In addition, the density of the metal- support boundary and its interaction with the active component were also increased. These characteristics of Ni/TiO2（TBT） led to a lower light-off temperature and a suppression of Ni sintering during CO methanation. As a consequence, the Ni/TiO2（TBT） exhibited better catalytic behavior, with a CO conversion of 99.4% and CH4 selectivity of 90.4% tinder the following conditions： p=1 MPa, t=320℃, n（H2）/n（CO）=3, gas hour space velocity （GHSV）=2×10^4 mL·g^-1·h^-1. The life test results of the two catalysts showed that Ni/TiO2（TBT） was more stable and the catalytic activity remained at its initial level after being used for 30 h.
