Electroconductive RGO-MXene membranes with wettability-regulated channels: improved water permeability and electro-enhanced rejection performance

● Electroconductive RGO-MXene membranes were fabricated. ● Wettable membrane channels were established between RGO and MXene nanosheets. ● Hydrophilic MXene reduces the resistance of water entering the membrane channels. ● Water permeance of RGO-MXene membrane is 16.8 times higher than that of RGO membrane. ● Electro-assistance can enhance the dye rejection performance of RGO-MXene membrane. Reduced graphene oxide (RGO) membranes are theoretically more conducive to the rapid transport of water molecules in their channels compared with graphene oxide (GO) membranes, as they have fewer oxygen-containing functional groups and more non-oxidized regions. However, the weak hydrophilicity of RGO membranes inhibits water entry into their channels, resulting in their low water permeability. In this work, we constructed wettable RGO-MXene channels by intercalating hydrophilic MXene nanosheets into the RGO membrane for improving the water permeance. The RGO-MXene composite membrane exhibits high pure water permeance of 62.1 L/(m²·h·bar), approximately 16.8 times that of the RGO membrane (3.7 L/(m²·h·bar)). Wettability test results and molecular dynamics simulations suggest that the improved water permeance results from the enhanced wettability of RGO-MXene membrane and increased rate of water molecules entering the RGO-MXene channels. Benefiting from good conductivity, the RGO-MXene membrane with electro-assistance exhibits significantly increased rejection rates for negatively charged dyes (from 56.0% at 0 V to 91.4% at 2.0 V for Orange G) without decreasing the permeate flux, which could be attributed to enhanced electrostatic repulsion under electro-assistance.     

Ceramic membrane fouling mechanisms and control for water treatment

● The fouling is summarized based on ceramic membrane performance and pollutants. ● The current research methods and theoretical models are summarized. ● The membrane fouling control methods and collaborative technology are reviewed. Membrane separation, as an important drinking water treatment technology, has wide applications. The remarkable advantages of ceramic membranes, such as chemical stability, thermal stability, and high mechanical strength, endow them with broader prospects for development. Despite the importance and advantages of membrane separation in water treatment, the technique has a limitation: membrane fouling, which greatly lowers its effectiveness. This is caused by organics, inorganic substances, and microorganisms clogging the pore and polluting the membrane surface. The increase in membrane pollution greatly lowers purification effectiveness. Controlling membrane fouling is critical in ensuring the efficient and stable operation of ceramic membranes for water treatment. This review analyzes four mechanisms of ceramic membrane fouling, namely complete blocking, standard blocking, intermediate blocking, and cake filtration blocking. It evaluates the mechanisms underlying ceramic membrane fouling and summarizes the progress in approaches aimed at controlling it. These include ceramic membrane pretreatment, ceramic membrane surface modification, membrane cleaning, magnetization, ultrasonics, and nanobubbles. This review highlights the importance of optimizing ceramic membrane preparation through further research on membrane fouling and pre-membrane pretreatment mechanisms. In addition, combining process regulations with ceramic membranes as the core is an important research direction for ceramic membrane-based water treatment.     

Prenatal diagnosis of severe combined immunodeficiency with defective synthesis of HLA molecules

The immunodeficiency associated with a defective expression of HLA molecules is an autosomal recessive disorder leading to death during childhood. We have performed prenatal diagnosis for six fetuses at risk for this disease by membrane immunofluorescence on blood lymphocytes and monocytes, using specific monoclonal antibodies for HLA class I and II molecules. Two pregnancies have been found to be affected. The diagnosis has been confirmed on each abortus by the study of the membrane expression of HLA class I and II molecules on blood lymphocytes and monocytes, and on thymic and splenic cells. The four other cases were found to be normal both during pregnancy and after birth. The detection of the defect as early as the 20th week of gestation allows selective termination.     

超滤法处理清洗乳化液废水的应用研究

采用自制超滤膜设备对上海拖拉机内燃机公司油嘴油泵 清洗乳化废水进行了实验室试验，和近一年的生产性应用，结果表明，清洗乳化液废水经超滤处理，ＣＯＤｃｒ去除率为８５％－９１％，油的去除率为９９．４％－９９．９％，出水添加适量新清洗剂后可以回用于生产。     

化工生产中的清洁工艺

简述了清洁生产产生的背景及其重要意义，从改进工艺（聚乙烯醇生产工艺改革），改变生产原料（以乙烯取代乙炔作为合成有机中间体的原料），应用生物技术（两步发酵法生产维生素Ｃ）和改变反应设备（离子膜法生产氢氧化钠）等４个方面说明清洁工艺在化工生产领域取得的实际成效。     

膜分离稀土废水预处理中钙镁去除的研究进展

稀土废水成分复杂,硬度高,利用膜法处理时,进膜之前必须进行预处理.介绍了降低稀土废水硬度传统的和新型的方法.经过分析得出,根据具体水质情况,选择适当的互补处理方法,稀土废水完全可达到膜分离装置进水水质要求.     

膜电除尘器-静电除尘新技术

膜电除尘器是将炭纤维或硅纤维编织膜作为集尘极的新式电除尘器,它克服了传统电除尘器存在的一些缺点,进一步提高了除尘效率,降低了电除尘器的造价,同时能去除粉尘中的酸性盐.介绍了膜电除尘器的结构、特点及除尘性能,并指出了进一步研究的方向.     

好氧生物处理污染水体的供氧技术

针对好氧生物处理污染水体需要充足的溶解氧，阐述了氧传递原理、传统供氧技术（机械供氧，鼓风供氧、氧载体供氧）和新型供氧技术（射流曝气供氧、膜供氧）。指出氧载体供氧和膜供氧技术具有广阔的应用前景。从材料，工艺及应用等方面详细介绍了膜供氧技术的研究进展，并对其发展前景进行了展望。     

膜—生物反应器特性影响因素研究

通过对外压管式膜组件与曝气池构成的好氧膜生物反应器的研究，分别考究膜组件的操作压力，膜面流速以及活性污泥混合液的污泥浓度，溶解性有机特的含量和温度等对膜通量的影响。     

A review of removal technology for antimony in aqueous solution

Antimony (Sb) and its compounds, toxic metalloid, have been classified as high-priority pollutants. Increasing Sb released into the water environment by natural processes and anthropogenic activities, which exposure threatens to human health and ecosystems. Therefore, it is of unquestionable importance to remove Sb from polluted water. Keeping in view the extreme importance of this issue, we summarize the source, chemistry, speciation, distribution, toxicity, and polluted situation of Sb about aqueous solution. Then, we provide the recent and common technology to remove Sb, which are based on adsorption, coagulation/flocculation, electrochemical technology, membrane technology, ion exchange, etc. In this review, we focus in detail on the adsorption method, researchers at present have been investigating to discover more advanced, cost-effective, eco-friendly, reusable adsorbents. However, to date the Sb-containing wastewater treatment technologies are not sufficiently developed and most of research have been tested only in controlled lab conditions. Few reports are available that include field studies and applications. We critically analyzed the salient features and removal mechanisms, evaluating benefits and limitations of these technologies, hoping to provide more references for further research. Finally, we considered the Fe- or Mn-based technologies was the most promising technique to remove Sb for field application.