SELECTIVELY LEACHING RECOVERY PROCESS OF SELENIUM

摘要

PROBLEM TO BE SOLVED: To safely recover high space selenium simple substance at a low cost without being subjected to roasting or distillation by selectively leaching selenium from a selenium-containing solid substance containing impurities. SOLUTION: When a selenium containing substance is leached using a water- soluble sulfite, selenium is selectively leached by allowing a reducing agent having higher reducing power than that of the sulfite to act on the selenium containing substance and then selenium simple substance is recovered by precipitating and separating. The recovered selenium simple substance is red selenium. Crystallization is accelerated by treating the recovered selenium with warm water of >=50 deg.C and containing no selenium compound, and further heat-treating in air.