Method for preparing composite catalyst by extracting aluminum from phosphogypsum

Abstract

The invention discloses a method for preparing a composite catalyst by extracting aluminum from phosphogypsum, comprising the following steps: carrying out acid leaching of waste gypsum, separating and purifying aluminum to prepare gamma-Al2O3, and modifying ZSM-5 by using the prepared gamma-Al2O3 sample to obtain the composite catalyst. By the method, part of impurities in phosphogypsum are removed to realize recycling of the phosphogypsum solid waste; and by the utilization of properties of impurities, the prepared gamma-Al2O3(at)ZSM-5 composite catalyst has long life, product selectivity ishigh, and reaction temperature is reduced.

Description

technical field

[0001] The invention relates to a method for preparing a composite catalyst by extracting aluminum from phosphogypsum, which belongs to the field of catalyst preparation. Background technique

[0002] ZSM-5 catalyst is used in the field of preparing other chemical products from methanol. It has a relatively large pore structure and relatively low product selectivity. Usually, ZSM-5 is modified by modifying to prepare hierarchically porous molecular sieves to narrow the pores and enhance the shape-selective function, thereby improving product selectivity. In addition, in the reaction process of preparing other chemical products with methanol, the temperature is mostly above 400 °C, and the carbon deposit formation rate has an exponential growth relationship with the reaction temperature, which makes the catalyst life short. Therefore, the modified composite catalyst can reduce the reaction temperature of the system, effectively alleviate the formation rate of...