| 摘要 |
The invention concerns a method for production of a catalyst, which is effective for spontaneous decomposition of hydrazine, during which a) into the pores of a carrier which has a pore volume of at least 0.1 cm<3>/g and a specific surface area expressed in m<2>/g that is equal to 195, Cp + 0.013 + 0.736 Vp, where Cp is the specific heat of the carrier at approximately 25 degrees C, expressed in cal/g, and Vp is the pore volume of the carrier, expressed in cm<3>/g, is introduced a solution of a salt containing iridium salts or mixtures of salts of iridium and ruthenium, which salt undergoes decomposition at a temperature in excess of 450 degrees C, wherein the solution contains said salt in a quantity of between around 0.02 and around 0.6 gram-atoms of metal per litre and has a pH of approximately 0.5 to approximately 4, b) the solution-containing carrier is dried to precipitate the salt in its pores, c) the carrier is then heated in order to break down the precipitated salt, d) the pores of the carrier are again impregnated with said salt solution, e) the carrier is again dried and the salt is caused to decompose, f) the impregnation of the carrier with the salt, the drying of the reimpregnated carrier and the breakdown of the precipitated salt are repeated at least seven times until the catalyst contains around 20 wt.percent to around 40 wt.percent of said metal, and g) the catalyst is heated in a hydrogen gas stream at a temperature between around 200 and around 500 degrees C to convert the products of decomposition of the precipitated salt into catalytically active metal. According to a preferred embodiment of the method, the carrier consists of beads of aluminium oxide and the beads are immersed in an ammonia solution of an iridium salt, after which the above-mentioned steps b)-g) are carried out. |
