Rapid and Continuous Extraction of Methyl Red from Wastewater Using Counter Current Chromatography

A new prototype and simple low speed counter current chromatography (LSCCC) has been fabricated and a laboratory work has been carried out for rapid and continuous removal of methyl red from wastewater using xylene as an extractant. The distribution ratio (D) and percentage of recoveries were calculated. The optimum concentration for extraction of methyl red was in the range of 2 × 10-4 to 8 × 10-4 mol·L-1. Maximum extraction achieved at pH range of 2 to 4.5. Various dye concentrations and solvent effects were studied to optimized conditions. It was shown that when the ratio of the organic phase to aqueous phase increased to more than 3:1, the striping efficiency decreased sharply. The experiments were carried out for 5 times and the highest extraction achieved was 99.8 per cent by two-solvent system LSCCC in just 5 minutes. Real wastewater samples were analyzed and the efficiency of the technique was compared with liquid-liquid extraction (LLE). In practice it was shown that although both techniques are rapid, the efficiency of the LSCCC is much better than LLE.

可控移动式顶抽除尘罩系统在不锈钢连铸切割中的应用

为解决不锈钢铸坯在线切割时产生的金属粉尘污染工作环境的问题,设计并制作了一套可控移动式顶抽除尘罩系统,在保证除尘效果的前提下,有效实施对切割区域的散热,保证切割机和辊道系统的正常使用。

连续带渣浸提法提取天然烟碱

采用连续带渣浸提法从烟草中获取烟碱 ,通过研究烟碱在溶剂相、水相和烟叶渣之间的分配特征 ,确立了浸提过程的关键控制因素。在控制烟叶初始含水量 30 %～ 50 %、原料超声波处理、调整无机碱添加量为烟叶量的 3%～ 5%等的基础上 ,将烟叶浸泡和液液萃取两步同时进行。确定萃取时间、级数、溶剂比后 ,在日处理 2 0kg烟叶的中试装置进行 4级连续逆流放大实验 ,平均萃取率超过 90 %。整个过程基本无废水排放 ,工艺过程缩短。采用富含正己烷的 6号溶剂油也是本工艺的一大特点 ,萃取效果好 ,毒性低 。

湖北建始县建业镇土壤有机质光谱特征分析

以湖北省建始县建业镇行政区内158个土壤样品有机质含量及其对应反射率光谱为数据源,对土壤有机质的光谱特征进行分析。通过九点加权平均滤波对光谱曲线进行噪声去除,对噪声去除后的反射率光谱进行包络线去除、倒数变换、对数变换、指数变换、一阶微分等12种数学变换,然后将反射率光谱与土壤样品有机质含量进行相关性分析,提取敏感波段,并基于包络线去除提取敏感波段范围内的吸收深度、吸收高度、吸收高差、吸收谷面积、吸收位置等特征参数,提取的特征参数与土壤有机质含量进行相关性分析,最后将敏感波段作为入选变量进行多元逐步回归,建立土壤有机质含量的拟合模型。结果表明,经过倒数一阶微分变换后反射率光谱对土壤有机质最为敏感;经过相关性分析后得到两个对土壤有机质敏感的波段范围分别是600~800 nm、2185~2223 nm;通过敏感波段包络线去除的光谱曲线及光谱特征曲线的结果观察到在2133~2268 nm有一个可能的吸收谷;在敏感波段范围内所提取的特征参数中对土壤有机质含量最为敏感的是吸收谷左面积;基于敏感波段的倒数一阶微分变换的多元逐步回归模型对土壤有机质的拟合结果最好,决定系数R 2为0.785,总均方根误差RMSE为0.523。可利用遥感高光谱快速、大区域预测土壤有机质含量。

铜电解液净化脱砷新工艺

总结了萃取法和连续电积法两种铜电解液净化脱砷新工艺的特点，并进行了分析比较。