锰渣-赤泥吸附剂制备及其对铜（Ⅱ）吸附性能

锰渣是锰矿石生产硫酸锰过程产生的酸性过滤渣,赤泥是拜耳法生产氧化铝过程产生的碱性废渣,两种废渣排放量大,综合利用程度低。以锰渣和赤泥为原料,混合焙烧制备锰渣-赤泥吸附剂,实现了两种废渣的中和,制得的吸附剂pH接近中性。研究了锰渣-赤泥吸附剂对溶液中2价铜离子的吸附性能,为废渣的综合利用提供新途径。考察了吸附时间、溶液初始铜离子质量浓度、溶液pH等条件对吸附剂吸附溶液中铜离子的影响。结果表明：不同焙烧温度制得的吸附剂对铜离子的吸附平衡时间为22 h;焙烧温度为700 ℃制得的吸附剂（A700）对铜离子的吸附效果最好,在固液质量体积比（g/L）为0.4∶1条件下,达到平衡时溶液中铜离子的质量浓度可从20 mg/L降低到0.053 mg/L,平衡吸附量为45.739 2 mg/g,对铜离子的吸附去除率达到99.72%。吸附剂A700对铜离子的吸附符合准一级动力学模型和Langmuir等温吸附模型。

Preparation of manganese residue-bauxite residue adsorbent and its adsorption capacity on Cu 2+

Manganese residue is an acidic filter residual produced in the process of producing manganese sulfate using pyrolusite,and bauxite residue（red mud） is an alkaline waste derived from Bayer process of producing alumina.Both of the two kinds of waste residues have large amounts of discharge and low comprehensive utilization rates.Manganese residue and red mud were used as raw materials to prepare adsorbents by mixing and roasting,through which the two kinds of waste residues can be neutralized and the pH of the prepared adsorbent is close to neutral.The adsorption property of the manganese residue-bauxite residue adsorbent on copper ion was studied.And a new route for comprehensive utilization of waste residues was provided.Effect of the conditions,such as adsorption time,initial mass concentration of Cu ²⁺ in solution and pH of solution etc.,on the Cu ²⁺ in solution of adsorbent were investigated.Results showed that the adsorption equilibrium time of Cu ²⁺ was 22 h by the adsorbents under different roasting temperatures.The adsorbent prepared under the roasting temperature of 700 ℃（A700） presented the best capacity on the adsorption of Cu ²⁺.Under the conditions of solid-liquid mass-volume（g/L） ratio of 0.4∶1,The concentration of copper ion in the solution can be reduced from 20 mg/L to 0.053 mg/L atthe adsorption equilibrium,the adsorption capacity was as high as 45.739 2 mg/g and the adsorption rate on Cu ²⁺ was 99.72%.The adsorption behavior of adsorbent A700 on Cu ²⁺ was demonstrated following the pseudo first-order kinetic model and Langmuir isothermal adsorption model.