The effectiveness of Soxhlet extraction as a simple method for GO rinsing as a precursor of high-quality graphene

Abstract

Graphite-oxide (GO) is a valuable compound produced by the chemical oxidation of graphite. The procedure for converting graphite into GO includes two steps: oxidation and subsequent rinsing. Proper rinsing is essential to obtain processable and applicable graphite-oxide. Traditionally, the rinsing involves filtration or centrifugation; both processes are extremely time-consuming, expensive, unsafe, and produce environmentally hazardous liquid waste in large volume. This study reveals an alternative method to rinse graphite-oxide using a Soxhlet extractor. Since only the vapor of the solvent is used for washing, Soxhlet rinsing offers reuse of the same solvent for many automatic subsequent cycles, leading to considerable solvent savings, reducing pollutants and work time, and ensuring safer production. The quality of the produced GO is evaluated by Raman spectroscopy, X-Ray diffraction (XRD), inductively coupled plasma (ICP), elemental analysis, and electron microscopy. Moreover, we test the electrochemical performances of reduced GO (rGO), the main final product of graphite-oxide. Finally, we discuss the benefits involved in the suggested rinsing method and compare its profitability with traditional methods. Soxhlet rinsing is favored environmentally and economically. Particularly, the automatic operation of many washing sequences saves labor time, and the reuse of the washing solvent spares a large volume of chemically deleterious solvents.