电镀污泥氨浸渣中铬的回收

以电镀污泥氨浸渣为研究对象,采用钠化氧化焙烧方法,实现了铬物相的转化和回收。钠化氧化焙烧过程以Na_2CO_3作为钠化剂,掺量为20%(质量分数),在750℃下焙烧2.5h,铬的转化效果最佳。X射线光电子能谱结果表明,钠化氧化焙烧实现了氨浸渣中铬由非水溶态Cr(OH)_3向水溶态Na_2CrO_4的有效转变。在室温条件下水浸,固液比1g∶10mL,浸出5min,铬浸出率可达到91.36%。热力学计算结果显示,Cr(OH)_3与O_2、Na_2CO_3反应的吉布斯自由能为负值,表明Cr(OH)_3易于生成Na_2CrO_4,Na_2CrO_4易溶于水,易于回收。     

饮用水的生物脱氮

饮用水的硝酸盐浓度超标已引起世界各国的高度重视，这是因为摄入过量的硝酸盐可导致婴儿的高铁血红蛋白血症；硝酸盐和亚硝酸盐转化为亚硝胺，则具有“致癌、致变和致畸”作用[1]。由于生物处理具有高效低耗的特点，饮用水的生物脱氮得到了广泛而深入的研究。本文拟就此作一综述。1电子供体的选择生物脱氮实质上是硝酸盐作为脱氮菌呼吸链的末端电子受体而被还原为气态氮化物的过程。要使该生物反应顺利进行，必须为其提供合适的电子供体。曾被用作电子供体的物质很多，从物理状态上看，涉及气体[2]、固体[3]和液体[4]3种状态；从化学成分上…     

氨法回收人造金刚石酸洗废液中的镍,钴,锰

本文用氨法处理人造金刚石酸洗废液，从而分离回收镍，钴锰。适当控制工艺参数及条件，可获得良好的镍，钴分离效果。     

焦炉煤气净化新工艺

焦炉煤气进行脱硫脱氰净化处理，采用国内先进水平的氨硫循环洗涤，克劳斯法回收硫技术，收到良好的环境效益和经济效益。     

Chemical behavior of organic compounds in the interface of water/dual-cation organobentonite

The sorption behavior of polar of ionizable organic compounds,such as p-nitrophenol,phenol and aniline,in the water/organobentonite systems is investigated.Both adsorption and partition occur to the sorption of organic compounds to dual-cation organobentonites.The separate contributions of adsorption and partition to the total sorption of organic compounds to dual-cation organobentonites are analyzed mathematically in the first time.The factors to the contributions are also discussed.The results indicated that the contribution of adsorption and partition is related to the composition and ratio of dual-cation surfactants exchanging onto the bentonite.The sorption of organic compounds to dual-cation organobentonite is dominated by adsorption at low concentrations and by partition at high concentrations,making the organobentonites powerful sorbents for organic contaminants over wide range of concentrations.