| 摘要 |
<p>1,213,098. Sulphur purification. EMPRESA AUXILIAR DE LA INDUSTRIA S.A. 8 April, 1969 [23 April, 1968], No. 18014/69. Heading C1A. Crude sulphur, obtained from iron pyrites or other similar sulphur-containing ores, is purified by treating the crude sulphur suitably at an elevated temperature with an aqueous acid leaching liquor which includes an oxidizing agent for quantitatively transforming arsenic sulphide contained in the crude sulphur into sulphuric and arsenic acids, decanting the leaching liquor and washing the purified sulphur thus obtained. Suitable specified oxidizing agents are an aqueous solution of an alkali metal or alkaline-earth metal hypochlorite, an aqueous solution of chlorine, a vapour of an oxide of nitrogen, an alkali metal nitrate, nitric acid, or a mixture of any of these with an aqueous solution of an alkali metal or alkaline-earth metal chloride, hydrochloric acid or sulphuric acid. The leaching liquor may be purged of the sulphuric and arsenic acids and recycled to treat further crude sulphur.</p> |
