Research On Production Of Insoluble Sulfur By Low Temperature Method

This thesis gave a relatively comprehensive review in technical progress.of insoluble sulfur (IS) at home and abroad. Based on the background of low temperature molten method for insoluble sulfur production with normal sulfur, the effect of technical conditions on sulfur polymerization into IS was studied. Meanwhile the polymerization stabilizers and new extractants for IS purification were investigated. The results show as following:the suitable conditions of normal sulfur polymerization into IS are reaction temperature 260℃, reaction time 60min, mass ratio of quenching medium to sulfur 12/1 and quenching medium at room temperature. The proper stabilizers added into polymerization system and quenching medium are KBr (by 0.05 m%) and ethylene glycol (by 0.6 m%) respectively. In this case, IS content in polymerization product can reached above 40%. The extraction efficiency of IS-R1 and AL-1/AH are close to carbon disulfur and other aspects such as recovery methods, solvent loss, safety and toxicity are superior to carbon disulfur. Therefore IS-R1 and AL-1/AH are hopeful to be the new extractant replacing carbon disulfur. By the low temperature molten polymerization, extraction with IS-R1 and oil-treatment with stabilizer, IS-7020 product is obtained and its thermal stability is above 90%which meet thermal stability requirement for insoluble sulfur.