Method for preparing activated carbon from rice husks

Abstract

The invention belongs to the field of preparation of activated carbon, and particularly relates to a method for preparing activated carbon from rice husks. According to the method, zinc chloride is used as an activator to treat substances, dissolved in zinc chloride, in raw material rice husks, saccharides such as glucose and the like are gradually decomposed and then further oxidized into uronic acid, uronic acid and aldose are condensed to form furfural, the furfural further has a polycyclic aromatization reaction to form condensed carbon, finally, an activated carbon structure is formed, the activated carbon structure is loose, the porous structure is more stable, and the specific surface area is larger. Alkali dissolution is performed with a sodium hydroxide solution, silicon dioxide in the rice husks is removed, and the porosity and activity of carbon are further increased. The more expensive zinc chloride can be recycled in the production process, raw materials are easy to obtain, the preparation process is pollution-free, and the product is low in impurity content, good in looseness, large in specific surface area and high in adsorption capacity.

Description

technical field [0001] The invention belongs to the field of activated carbon preparation, and in particular relates to a method for preparing activated carbon from rice husks. Background technique [0002] Activated carbon is a black porous solid carbon. Generally, it is produced by crushing, forming or carbonizing and activating coal with uniform coal particles. The main component is carbon, and contains a small amount of oxygen, hydrogen, sulfur, nitrogen, chlorine and other elements. The specific surface area of ​​ordinary activated carbon is 500~1700m 2 / g room. It has strong adsorption properties and is an industrial adsorbent with a wide range of uses. It is widely used in various fields. It is used in industry to decolorize and make the solution pure. It is used in medicine to absorb toxins, bacteria or gases in the stomach and intestines. It is used as an additive in cosmetics to remove grease; in water purification filters. Activated carbon is often used as a ...

AI Technical Summary

Problems solved by technology

The method for preparing activated carbon from dried fruit shells as disclosed in CN104512890A, and the method for producing activated carbon disclosed in CN103159214A all emphasize the use of natural organic matter as raw materials to prepare activity. Dried fruit shells, etc., all contain silica to form a protective mechanism. Professor Saito Hidetoshi of Nagaoka University of Technology and Science pointed out in his paper that if the plant fruit shells are simply heated to make charcoal, the residual silica will prevent it from functioning as activated carbon