Optimization of the preparation method of a mechanically strong carbon electrode

Abstract

Nowadays, a strategy for the utilization of secondary resources to obtain valuable components is actual. It will lead to the most rational use of natural resources and environmental protection. Electrochemical methods are perfectly applicable to solve this problem. Electrochemical methods allow concentrating of the target components without preliminary preparation of the raw material. Carbon materials (CM) based on plant and carbon-mineral raw materials are an excellent option as a matrix for obtaining the electrodes, due to their availability, low cost, high specific surface area, and the presence of different functional groups. The lack of theoretical substantiation of the adsorption phenomena on carbon electrodes served as an incentive for the study and development of a method for obtaining a mechanically strong electrode based on modified carbon and polyethylene. The design and mechanical strength of carbon electrodes (CE) are of great importance for the efficiency of purification and extraction of valuable components. In this article, we obtained carbon material from walnut shells by hydrothermal carbonization with further steam-gas activation (the specific surface area is 754.0 m2/g). The structural, physicochemical characteristics of the carbon material, binder, and carrier material were studied by the following methods: scanning electron microscope (SEM), Brunauer–Emmett– Teller (BET), thermogravimetric analysis and differential scanning calorymetry (TGA-DSC). The method of hot-pressing is applied for obtaining the carbon electrodes. Using the method of full-factor experiment and steepest ascent, the values of pressure and temperature during pressing and the ratio of carbon material: binder was optimized: P = 226 atm; T = 90.8 ℃; carbon material: binder ratio = 67.5:32.5 %, respectively.