Taking the sand-steel-slag as an adsorbent, the process conditions and mechanisms of acidic Cr6+ removal in waste water was studied. The results show that the optimal removal conditions are pH of 0. 8~1. 5, temperature of 20℃ ~25℃, sand-steel-slag adsorbent of 5g and the initial waste water input of 150~200mL. Cr6+ removal amount has a linear relation-ship with slag solution stewing time, the correlative coefficients of the intra-particle diffusion model, quasi-one rate equation, quasi-two rate equation, Langmuir and Freundlich isotherm model are greater, which is monolayer adsorption mode and has bet-ter adsorption. The mechanism analysis show that the adsorption process of sand-steel-slag to acidic Cr6+ can be divided into 4 stages:reduction phase ( lowering drug) , hydration phase, precipitation phase, adsorption stage. The maximum adsorption ca-pacity of sand-steel-slag is 45. 872mg/g, accounting for a smaller proportion of sand-steel-slag, so it can be used to pre-pare mortar and concrete, etc. after adsorption.%以砂样钢渣作为吸附剂,研究了去除废水中Cr6+的工艺条件和机理. 结果表明,最佳工艺条件分别为:pH值0. 8~1. 5,温度为20℃ ~25℃,钢渣投放量为5 g,废水初始体积以150~200 mL为宜. 铬去除量与钢渣水溶液静置时间呈线性关系,且颗粒内扩散模型、准一级和二级速率方程、Langmuir和Freundlich吸附等温模型拟合曲线的相关系数较大,属于单分子层的吸附方式并具有较好的吸附性. 通过机理分析可知,砂样钢渣对Cr6+的吸附过程分为还原(降毒)、水化、沉淀、吸附等4个阶段,钢渣最大吸附量为45. 872 mg/g,占砂样钢渣的比例较小. 钢渣完成吸附铬后,仍可用来配制砂浆、混凝土等.
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