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采用水热法合成了含有89%{101}晶面的TiO_2纳米锭(TiO_2-101)和77%{001}晶面的TiO_2纳米片(TiO_2-001),将其用作载体来制备担载钯催化剂;研究了上述制备的TiO_2纳米材料对Pd/TiO_2-101和Pd/TiO_2-001催化剂用于乙炔选择加氢制聚合级乙烯催化性能的影响。结果表明,Pd/TiO_2-101催化剂表现出更好的乙炔转化率和乙烯收率。通过氢气程序升温脱附(H_2-TPD)、氢气程序升温还原(H_2-TPR)、透射电子显微镜(TEM)、CO化学吸附、X射线光电子能谱(XPS)和热重分析仪(TGA)等对催化剂进行了结构表征和分析。TEM和CO化学吸附结果表明,Pd纳米颗粒(NPs)在TiO_2-101载体上有较小的颗粒尺寸(1.53 nm)和较高的分散度(15.95%);而Pd纳米颗粒在TiO_2-001载体上的颗粒尺寸是4.36 nm和9.06%的分散度。Pd/TiO_2-101催化剂上较小的Pd颗粒尺寸及其较高的分散度使催化剂具有更多的反应活性位点,这促进了其反应的催化活性。
TiO 2 nanoplates (TiO_2-101) containing 89% {101} crystal planes and 77% {001} crystal planes were synthesized by hydrothermal method, which were used as supports to prepare the supported The effects of the above-prepared TiO 2 nanomaterials on the catalytic performance of Pd / TiO 2-101 and Pd / TiO 2-001 catalysts for the selective hydrogenation of acetylene to polymerized ethylene were studied. The results show that the Pd / TiO_2-101 catalyst shows better acetylene conversion and ethylene yield. H 2 -TPD, H 2 -TPR, TEM, CO chemisorption, X-ray photoelectron spectroscopy (XPS) and thermogravimetric analysis (TGA) The catalyst was characterized and analyzed. TEM and CO chemisorption results showed that Pd nanoparticles (NPs) had a smaller particle size (1.53 nm) and a higher dispersion (15.95%) on the TiO_2-101 support; while the Pd nanoparticles were more effective on the TiO_2-001 support The particle size is 4.36 nm and 9.06% dispersion. The smaller Pd particle size and higher dispersion of Pd / TiO 2 -101 catalyst make the catalyst have more reactive sites, which promote the catalytic activity of the reaction.