Technology for preparing sulfur-free expandable graphite by utilizing high-concentration perchloric acid

Abstract

The invention discloses a technology for preparing sulfur-free expandable graphite by utilizing high-concentration perchloric acid. The technology comprises the following steps: adding hydrogen peroxide into flake graphite and uniformly stirring; then adding perchloric acid with the concentration of 98 percent and stirring in an ice water bath for 30 to 50 min, wherein the ratio of the hydrogen peroxide to the flake graphite to the perchloric acid is 1 to 5 to 10; after stirring, putting a mixture into a water bath with the temperature of 20 DEG C and oxidizing for 1 h; then washing with a perchloric acid solution with the concentration of 30 percent and performing suction filtration; then dropwise adding an anhydrous acetic acid solution with the concentration of 70 percent; stirring while dropwise adding the solution; after uniformly stirring, reacting for 20 min; then washing with water and perform suction filtration; drying under the temperature condition of 50 DEG C to prepare thesulfur-free expandable graphite. The perchloric acid and the hydrogen peroxide are used as oxidants and both have very strong oxidization performance; the oxidants are used for carrying out layered oxidization on the graphite, the oxidization is uniform and the oxidization depth is proper; the technology is simple in method and low in cost and the product contains no sulfur.

Description

technical field [0001] The invention belongs to the technical field of graphite, and in particular relates to a process for preparing sulfur-free expandable graphite by using high-concentration perchloric acid. Background technique [0002] Flexible graphite is a new type of functional material with excellent sealing performance. It is obtained by expanding expandable graphite at high temperature and is widely used. In the traditional process of preparing expandable graphite, the use of sulfuric acid causes harmful sulfur elements to remain in the flexible graphite, causing corrosion to the seals. Contents of the invention [0003] In order to overcome the above-mentioned technical problems in the prior art, the object of the present invention is to provide a process for preparing sulfur-free expandable graphite using high-concentration perchloric acid. [0004] A kind of technology that utilizes high-concentration perchloric acid to prepare sulfur-free expandable graphit...

AI Technical Summary

Problems solved by technology

In the traditional process of preparing expandable graphite, due to the use of sulfuric acid, harmful sulfur elements remain in the flexible graphite, which will corrode the seals