材料期刊网

在自制的冷凝回流浸取装置中,用四氯化碳浸取试样中的游离硫,过滤后将滤液浓缩至石英舟中,于1000℃管式炉中通氧气燃烧,生成的二氧化硫,以淀粉吸收液吸收,用碘量法测定.对CCl_4浸取游离硫的条件进行研究,结果表明,浸取温度、CCl_4的用量、浸取时间、称样量(硫量)以及在浸取过程中溶液的搅拌程度对测定结果都有影响.实验选用在60 mLCCl_4中加入1～5 g试样,于80℃恒温水浴上加热回流15～20 min的条件下进行浸取.方法用于二硫化钨中游离硫质量分数为0.65%～2.42%的样品测定,相对标准偏差在1.3%～2.7%之间.

Free sulfur in WS_2 sample was extracted by CCl_4 in a self-made condensate reflux extraction plant. The filtrate was concentrated into a quartz-boat, and then combusted in a tube-stove at 1 000 ℃by filling oxygen. The produced sulfur dioxide was absorbed with starch solution and then determined by iodimetry. The extraction conditions of free sulfur by CCl_4 were studied. The results indicated that the extraction temperature, dosage of CCl_4, extraction time, sampling amount (sulfur content) and the stirring of solution had all influence on the determination. In this study, 1-5 g of sample was added into 60 mL of CCl_4, and then extracted at 80 ℃ in thermostat water bath under refluxing for 15-20 min. This method was applied to the determination of tungsten disulfide sample containing 0.65-2.42 % (mass fraction) free sulfur. The relative standard deviations were in the range of 1.3 %-2.7%.