The effects of sulphurizing agent on the formation of calcium lanthanum sulphide

✍ Scribed by Ming Shyong Tsai; Min Hsiung Hon

• Publisher: Elsevier Science
• Year: 1994
• Tongue: English
• Weight: 573 KB
• Volume: 26
• Category: Article
• ISSN: 0921-5107
• DOI: 10.1016/0921-5107(94)90183-x

✦ Synopsis

For calcium lanthanum sulphide (CLS) formation, the effect of the sulphurizing agent is studied. CS 2 and sulphur are used as sulphurizing agents to sulphurize the lanthanum and calcium carbonate precursors which are formed by a coprecipitated method. With CS2 as a sulphurizing agent, the intermediate product formed is LaS 2 whereas when sulphur is employed, the La202S was the intermediate product. If LaS2 is formed first, it is not difficult to complete the sulphurizing reaction for CLS at a low temperature (700 °C) for a short soaking time (3 h). However, if the La202S is formed first, the phase formation reaction of CLS should be completed at a high temperature (800-1050 °C) for a long soaking time in order to dissociate the La-O bond.