摘要
This study focused on leaching behavior of alkaline anion and sodium in bauxite residue through ammonium chloride treatment.The results showed that the pH of bauxite residue decreased from 10.49 to 8.93,total alkaline anion(HCO3^-,CO3^2-,OH^-,AlO2^-)concentration reduced from 38.89 to 25.50 mmol/L,leaching rate of soluble sodium was 80.86%with ammonium chloride addition of 0.75%,liquid/solid(L/S)ratio of 3(mL/g),temperature of 30°C and reaction time of 18 h;L/S ratio was the main factor affecting the removal of alkaline anion and the leaching of sodium.Furthermore,ammonium chloride promoted the dissolution of diaspore and changed the micro/morphological characteristics with the increase of massive structure.The findings of this work will contribute to achieve soil-formation of bauxite residue.
研究氯化铵处理对赤泥碱性阴离子及钠离子浸出行为的影响。结果表明:在氯化铵添加量为0.75%、液固比为3、温度为30℃、浸出时间为18h的条件下,赤泥pH从10.49降至8.93,碱性阴离子(HCO_3^-,CO_3^(2-),OH^-,AlO_2^-)浓度从38.89降至25.50mmol/L,可溶性钠浸出率为80.86%;液固比是影响碱性阴离子和钠离子浸出的主要因素。氯化铵促进了赤泥中一水铝石的溶解及团粒结构的形成,有助于实现赤泥的土壤化。
基金
Projects(41877511,41842020) supported by the National Natural Science Foundation of China
Project(201509048) supported by the Environmental Protection’s Special Scientific Research for Chinese Public Welfare Industry
