Noble metal catalyst used in hydrocracking and isomerization of Fischer-Tropsch synthetic wax and preparation method therof

Abstract

The invention provides a noble metal catalyst used in hydrocracking and isomerization of Fischer-Tropsch synthetic wax and a preparation method thereof. The a catalyst carrier comprises the following components: 70 to 85 weight percent of amorphous silicon aluminum and 15 to 30 weight percent of alumina adhesive, wherein active components are selected from noble metal Pt and Pd elements (in a molar ratio of 0.1 to 0.6) and the noble metal active components account for 0.1 to 1 weight percent of the carrier; the specific surface area of the catalyst is 150 to 400m2/g, while the pore volume is 0.3 to 1.4ml/g and the NH3-TPD total acidity is between 0.5 and 1.5mmol/g; and 4 to 15nm pore distribution accounts for 60 to 90 percent of total pore volume respectively. The preparation method comprises the following steps: (1) adding the alumina adhesive, 1 to 5 weight percent pore-forming agent CMC of the amorphous silicon aluminum and 1 to 3 weight percent extrusion-aid agent sesbania powder into the amorphous silicon aluminum of required weight, extruding the mixture on an extruder after mixed kneading and roller compaction, and drying and baking to obtain the carrier; and (2) loading active components Pt and Pd noble metal elements by a common dipping method and then carrying out vacuum drying to obtain the catalyst through calcination.

Description

technical field [0001] The invention relates to a precious metal catalyst for hydrocracking and isomerization of Fischer-Tropsch synthesis wax and a preparation method thereof, more specifically to an amorphous silicon-aluminum precious metal catalyst for producing middle distillate oil and a preparation method thereof. The invention belongs to the technical field of cracking and isomerization of heavy distillate oil and wax synthesized by Fischer-Tropsch. Background technique [0002] In recent years, with the shrinking of the world's oil resources and the rise of crude oil prices, related research and technological progress in seeking oil alternative resources are in the ascendant. Synthesis gas (CO+H) is obtained by gasification of coal, natural gas or biomass 2 ), followed by conversion of syngas to hydrocarbons (CH) by Fischer-Tropsch synthesis, a process commonly referred to as XTL. The products of Fischer-Tropsch synthesis can be further processed to obtain high-qua...

AI Technical Summary

Problems solved by technology

However, at present, hydrocracking catalysts containing zeolite are used in the processing of heavy crude oil. These catalysts have relatively strong cracking ability. When applied to the processing of wax, the selectivity of middle distillates (including jet fuel and diesel oil) is poor.

[0005] Chinese patent 01111439.8 discloses a catalyst for producing diesel from Fischer-Tropsch synthesis product wax and its preparation method. In addition to using Y zeolite components, the catalyst uses alumina or a silicon-aluminum mixture as a dispersant. It is characterized in that it uses cobalt oxide or oxide At the same time, Mo or W oxide is used as the active component. Although the catalyst has the characteristics of high activity and high isomerization performance, the selectivity of medium oil of the catalyst is low

Although the catalyst has high medium oil selectivity, its activity is low. To achieve 60% conversion rate, the reaction temperature is generally above 400°C