A kind of preparation method of low ash briquette coal-based activated carbon

Abstract

The invention provides a method for preparing low-ash briquette coal-based activated carbon, which belongs to the technical field of activated carbon. The preparation method includes the following steps: oxidizing and drying non-caking coal and long-flame coal in a ratio of 10 by weight: (1 ‑3) Mixing, adding a modified phenolic resin binder with a weight of 1‑3% of the mixed coal material, pressing and molding, then performing high-temperature carbonization and pyrolysis, drying and sieving, and gas activation in sequence, adding sodium hydroxide and potassium hydroxide A mixed solution of sodium bicarbonate and sodium hexametaphosphate is obtained by hot-dipping the treatment liquid; the low-ash briquette coal-based activated carbon has low ash content and high mechanical properties, and can retain activated carbon to the greatest extent The microporous structure can meet the requirements of industrial applications.

Description

technical field [0001] The invention relates to the technical field of activated carbon, in particular to a method for preparing low-ash briquetted coal-based activated carbon. Background technique [0002] Activated carbon is a hydrophobic adsorbent made from carbon-containing substances as raw materials, which is carbonized and activated at high temperature. Activated carbon contains a large number of micropores, has a huge specific surface area, can effectively remove color, odor, and remove organic pollutants and some inorganic substances in water bodies. It is widely used in environmental protection, chemical industry and other fields. Therefore, its The demand is increasing year by year. my country has abundant coal reserves, which can be effectively used to prepare coal-based activated carbon. According to different raw materials, coal-based activated carbon is divided into crushed activated carbon, columnar activated carbon and briquetted activated carbon, etc. Amo...

AI Technical Summary

Problems solved by technology

[0003] The formability and porosity of briquetted activated carbon are good, but the ash content is high, and the requirements for the production of raw coal are also high. It needs low ash content and suitable cohesiveness. Among them, weakly cohesive coal is suitable for , it is possible to prepare briquetted activated carbon whose adsorption index meets the requirements, but the reserve of this kind of weak caking coal is very limited

[0004] Strength is an important indicator of the performance of briquetted activated carbon. High-strength coal molding is also the basis for preparing high-strength activated carbon. Therefore, most coal powder molding technologies still need to add various binders such as coal tar pitch. Commonly used adhesives such as coal tar pitch and coal tar The binder will melt and volatilize after heating, so that the strength of the final product is not high, and in the production of activated carbon, residues such as coal tar pitch will block the pores of activated carbon, which is not conducive to improving the quality of activated carbon; Binder-free coal-based activated carbon has been developed. However, in order not to add a binder, a large amount of weakly cohesive coal and highly cohesive fat coal have to be added to the pulverized coal raw material. The addition of carbonization requires a slow increase in temperature to prevent the particles from foaming during carbonization, and a long activation time is required to obtain a sufficiently large surface area of ​​activated carbon