无硫高膨胀倍数可膨胀石墨的制备研究

Preparation of High Expansion Ratio Sulfur-free Expandable Graphite

以浓硝酸为插入剂,高锰酸钾为氧化剂制备无硫可膨胀石墨。对相关影响因素做了详细的探讨,得出最佳工艺条件为石墨(g)∶硝酸(mL)∶高锰酸钾(g)=1.0∶2.0∶0.15。反应温度20℃,反应时间为75min。该工艺制备的试样的膨胀体积可达500倍。与已有的工艺相比,该方法制备的膨胀石墨不含硫,膨胀充分,成本低,操作简单。

Sulfur-free expandable graphite was synthesized using the nitric acid as the oxidant and acetic acid as the inserting reagent,KMnO4 as oxidant.The influence factors were discussed in detail,The optimized experimental conditions as follows：the raw flaky graphite（g）∶the nitric acid（mL）∶potassium permanganate（g）=1.0∶2.0∶0.15,the reaction time is 75 minutes at 20 ℃.The expanded volume of the sample preparing by this method is over 500.Compared with the existing technology,this method is the sulfur-free,the full expansion of low cost,easy to operate.