Preparation method of coal-based activated carbon for nitrogen/methane separation and prepared activated carbon

Abstract

The invention discloses a preparation method of coal-based activated carbon for nitrogen/methane separation and the prepared activated carbon. The preparation method comprises the following steps: taking anthracite as a raw material, and crushing; uniformly mixing the pulverized coal obtained by crushing with a binder, an activated catalyst and water to obtain a mixture; carrying out pressure molding on the obtained mixture, and naturally airing molded strips to cure the molded strips; putting the cured molded strips into a carbonization furnace, and carbonizing the molded strips under the condition of air isolation; putting the obtained carbonized material into an activating furnace, and performing activating by adopting carbon dioxide gas as an activating agent to obtain the coal-based activated carbon for nitrogen/methane separation. By selecting suitable coal types, improving the production process and simplifying the preparation process, the preparation process of the coal-based activated carbon for nitrogen/methane separation suitable for large-scale production is successfully researched, and the purpose of preparing a high-performance activated carbon adsorbent at low cost is achieved.

Description

technical field [0001] The invention relates to the field of coal-based activated carbon, in particular to a coal-based activated carbon for nitrogen / methane separation and a preparation method thereof. Background technique [0002] my country's coalbed methane, oilfield gas and landfill gas contain a large amount of CH4 gas, such as the volume fraction of CH4 in oilfield gas is about 70%-80%, the volume fraction of CH4 in landfill gas is about 60%, and the volume fraction of CH4 in coal mine gas The content of CH4 is relatively small, and the volume fraction is about 20%-50%. The utilization of these methane gases can effectively improve the energy structure and reduce greenhouse gas emissions. Because the physical properties of N2 and CH4 are similar, it is difficult to separate them by conventional physical methods. Pressure swing adsorption (PSA) technology uses the principle of kinetic effect or equilibrium effect. When the ratio of the equilibrium separation coefficien...

AI Technical Summary

Problems solved by technology

[0005] Currently, about CH 4 / N 2 There are relatively few studies on PSA activated carbon for separation, especially fewer reports on the preparation of this type of pressure swing adsorption carbon using coal as raw material, and the preparation process is cumbersome, which does not have engineering application value economically.

For example, CN200910103409.5 discloses a preparation method of shaped activated carbon, which specifically goes through technological procedures such as pulverization, air pre-oxidation, kneading, molding, carbonization, activation, water washing and drying. The carbonization and activation processes are all carried out under nitrogen protection, and It involves air pre-oxidation, water washing, drying and other processes, which will inevitably lead to an increase in manufacturing costs in actual production

CN02117916.6 discloses a high specific surface area activated carbon, the specific surface area is 1700m 2 / g above, it is only mentioned that the activated carbon can realize CH 4 / N 2 Separation of , did not explain the adsorption effect

In addition, the higher the specific surface area, it does not mean that the separation effect is better, and usually only increases the preparation cost