无硫膨胀石墨制备及影响因素分析

Preparation of Sulfur-free Expanded Graphite and Its Influencing Factors

以鳞片石墨、硝酸、双氧水、磷酸为原料,采用化学法经氧化酸化插层、水洗、干燥、高温膨胀过程制备无硫膨胀石墨。利用正交试验方法确定最佳工艺条件,并对相关影响因素作了分析。结果表明:按鳞片石墨、硝酸、双氧水、磷酸质量比1∶1.2∶0.2∶1.5,反应时间80 min,反应温度40℃,膨化温度900℃的条件下可以制备出膨胀体积为312 mL/g的无硫膨胀石墨,相关影响因素的大小依次为磷酸、双氧水、硝酸、反应时间。

Sulfur-free expanded graphite prepared by chemical oxidation intercalation acidification, washing, drying, heat expansion process with flake graphite, nitric acid, hydrogen peroxide, phosphoric acid as raw materials. The optimum conditions were determined by orthogonal test method, and related factors were analyzed. The results show that sulfur-free ex- panded graphite of the expansion volume 312 mL/g could be produced Under the optimum conditions with the weight ratio of natural flake graphite, nitric acid, hydrogen peroxide and phosphoric acid being 1 ： 1.2 ： 0. 2 ： 1.5, reaction time of 80 min, reaction temperature 40 ℃, and expanding temperature 900℃. The descending order of affecting factors is phosphoric acid, hydrogen peroxide, nitric acid and the reaction time.