METHOD OF PREPARING FISCHER-TROPSCH CATALYST PRECURSOR Russian patent published in 2004 - IPC

FIELD: polymerization catalysts. SUBSTANCE: catalyst precursor preparation is started with treating suspension containing catalyst carrier, active component precursor, and water at elevated temperature T₁ (60-95^o) and subatmospheric pressure P₁ (up to vacuum 20 kPa at 60^o and up to vacuum 83 kPa at 95^o) so that carrier is impregnated with active component precursor and partially dried. Initial treatment stage is no longer continued when impregnated carrier achieves calcination loss below 1.2 calcination loss obtained at original wetness (LOI_iw). In the next treatment step, partially dried impregnated carrier is exposed to elevated temperature T₂ and subatmospheric pressure P₂ is maintained such that following conditions are satisfied: 60^o <T₂ ≤95^o and T₂>T₁ and/or P₂ <20 kPa and P₂<P₁. Catalyst can further be obtained by reducing its precursor. Method also provides for storage of dry impregnated carrier after subsequent treatment under dry conditions at ambient temperature prior the material is subjected to calcination. Allowable storage time should be shorter than ((-8,1/LOI_iw)LOI_unload+26,2) hours, where LOI_unload represents loss at which preceding treatment step was ended. Excellent properties of catalyst achieved upon drying are preserved until calcination. EFFECT: enhanced catalytic efficiency due to optimized drying conditions. 27 cl, 6 dwg, 7 tbl, 11 ex