粉磨酸浸-氯化氢通气结晶法提取粉煤灰中氧化铝

摘要

Grinding-acid-leaching and HCl gas sparging technology was used for preparing Al2O3 from coal fly ash.First,Al was leached out from coal fly ash by mechanical grinding and hydrochloric acid leaching.Then,the Al3+ in the leached liquid were crystallized by sparging HCl gas and pure aluminum chloride(AlCl3·6H2O) was obtained by filtering and washing with hydrochloric acid.Finally,the pure AlCl3· 6H2O was calcined to Al2O3 product.The optimal conditions of the whole technology were determined by experiments.The extraction efficiency of Al2O3 can reach 80.35％ under the optimal conditions and the quality of the Al2O3 product(99.29％) was up to the technical indicator of YS/T 803—2012(AO-1) standard.%采用粉磨盐酸酸浸联合氯化氢通气结晶法从煤粉炉粉煤灰中提取氧化铝.首先,通过将煤粉炉粉煤灰机械粉磨活化后,用盐酸将灰中氧化铝浸出于酸浸液中;然后,采用向酸浸液通入氯化氢气体的方法,将溶液中铝离子结晶析出为六水氯化铝晶体,经过滤分离-洗涤除去杂质离子后得到纯净的六水氯化铝;最后,将所得六水氯化铝煅烧得到最终氧化铝产品.通过实验研究确定了该工艺的最佳条件,氧化铝提取率最高可达80.35％,纯度为99.29％,达到冶金级氧化铝一级标准[YS/T803—2012(AO-1)].