CATALYST FOR PRODUCING SULFUR FROM ACIDIC GASES AND METHOD OF PREPARATION THEREOF Russian patent published in 1997 - IPC

FIELD: preparation of catalysts. SUBSTANCE: invention relates to catalysts used in production of sulfur from acidic gases according to Claus method, in particular, to so called protective-bed catalysts serving as protectors for main-bed catalysts against oxygen in reactors of Claus plants and reactors for afterpurification of tail gases. Catalyst contains alumina and iron oxides and additionally magnesium and silicon oxides, and also phosphates of indicated metals (2.0-14% FeO and Fe₂O₃, 1-1.5% SiO₂, 0.3- 0.5% MgO, 0.5-1.0 P₂O₅, and Al₂O₃ - the balance). Alumina is mechanically mixed with iron oxide and hydroxide, silicon and magnesium oxides followed by plasticization of mixture by adding 20- 30% phosphoric acid aqueous solution, granulation, and heat treatment of granules. Ratio of starting components (on conversion to oxides) is: Al₂O₃ : Fe₂O₃ : SiO₂ : MgO : P₂O₅ = 1: (0.013-0.107):(0.019- 0.028):(0.009-0.015):(0.0004-0.007). Heat treatment of catalyst is conducted in linear heating condition with rate 1-2 C/min in temperature range 20-120 C with subsequent aging for 2-3 h, then with rate 2-3 C/min within the range 120-550 C and aging for 3-4 h. Finally cooling is performed at the rate 4-5 C/min. EFFECT: improved quality of catalyst. 4 cl, 1 tbl