Effect of preparation conditions on platinum metal dispersion and turnover frequency of several reactions over platinum-supported on alumina catalysts

• DOI: 10.1016/j.apcata.2004.06.005
• Publication Date: 2004-07-21T18:22:43Z
• Authors: Hiromi Matsuhashi; Satoru Nishiyama; Hiroshi Miura; Koichi Eguchi; Koji Hasegawa; Yasuo Iizuka; Akira Igarashi; Naonobu Katada; Junya Kobayashi; Takashi Kubota; Tohru Mori; Kazuyuki Nakai; Noriyasu Okazaki; Masatoshi Sugioka; Takashi Umeki; Yoshiteru Yazawa; Daling Lu
• Keywords: preparation conditions; dispersion; platinum; 02 engineering and technology; 0210 nano-technology; alumina; 7. Clean energy; 01 natural sciences; turnover frequencies; 0104 chemical sciences

To obtain a broad understanding of the effect of preparation conditions on the platinum metal dispersion and the effect of dispersion on turnover frequencies (TF) of several representative reactions, we prepared platinum-supported alumina catalysts by impregnation methods in which preparation conditions were fixed or not fixed using certain alumina. Platinum dispersions on the alumina catalysts were determined by several methods. Catalytic activities for combustion of propane, oxidation of CO, hydrogenations of ethylene and naphthalene, hydrodechlorination of 1,1,1-trichloroethane, hydrodesulfurization of thiophene, and hydrocracking of hexane were compared based on the TF of these reactions. The following results were obtained: (i) high dispersion of platinum was achieved without extra modification for the catalyst preparation method; (ii) an attentive pretreatment brought high reproducible results in platinum dispersions; (iii) the catalytic activities for combustion of propane, hydrodesulfurization of thiophene and hydrogenation of naphthalene were affected by starting materials of platinum; (iv) the relation between the TF and platinum dispersion was negative in all reactions tested except hydrocracking of hexane.