NTE: Removal of Toxic Metal Ions from Contaminated Water by Dendrimer Enhanced Ultrafiltration

ABSTRACTProposal没有。项目类型：环境倡议新技术（00-49）主要研究者：Mamdou S. diallo机构：霍华德大学NTE：树状聚合物增强超滤去除污染水中的有毒金属离子有毒金属离子排放到公有水处理厂（POTWs）、地表水体、含水层和沿海水系统中已经在全世界造成了一个重大的水污染问题。聚合物增强超滤（PEUF）是一种有前途的处理有毒金属离子污染的水的方法。在PEUF中，将一种对有毒金属离子具有强结合亲和力的水溶性聚合物添加到被污染的水中。所得溶液通过孔径小于金属离子负载聚合物的超滤膜（UF）。利用PEUF获得了高纯度的渗透物。该项目利用纳米化学的最新进展，如树状大分子的发明，为PEUF开发更高效、更经济的功能材料。树状大分子是高度支化的聚合物，具有可控的组成和结构，由三部分组成：核心功能，内部分支细胞和末端分支细胞。树状大分子的关键性质，如尺寸、形状、核心化学、表面化学和多分散性，可以通过明智地选择合成构件和反应条件来控制。例如，树突分子的末端基团可以设计成与特定表面相容或不相容，而其核心可以作为金属离子的受体。该项目的总体目标是评估树状聚合物增强超滤（DEUF）作为一种高效、环保、经济的处理有毒金属离子污染的水的方法的可行性。商业树状大分子正在被化学修饰，以确定不同形式的树状大分子在分离铜、锌和镉离子方面的有效性。树状大分子污染UF膜的倾向也在测试中。金属制品和机械（mp&m）行业是DEUF应用的首要目标。在塑料行业的7万家公司中，大约有4万家产生的废水受到有毒金属离子的污染。根据现行法规，塑料行业必须在排放到污水处理厂之前对其污染的废水进行处理。环境保护署正在为塑料工业颁布新的更严格的污水浓度限制。使用目前可用的最佳可行控制技术遵守这些新条例的额外费用估计为每年19.5亿至35.9亿美元。EPA对PEUF工艺的初步评估表明，与化学沉淀法相比，PEUF工艺具有成本效益，化学沉淀法是mp&p行业的废水处理基准技术。由于树状大分子的金属离子结合能力明显大于目前在PEUF中使用的线性聚合物，使用DEUF应该会带来更有效的水净化，并为MP&amp； M行业节省大量资金。

ABSTRACTProposal No.: CTS-0086727Proposal Type: New Technologies for the Environment Initiative (00-49)Principal Investigators: Mamdou S. DialloInstitution: Howard University NTE: Removal of Toxic Metal Ions from Contaminated Water by Dendrimer-Enhanced UltrafiltrationThe discharge of toxic metal ions into publicly owned water-treatment works (POTWs), surface water bodies, aquifers and coastal water systems has caused a major water contamination problem throughout the world. Polymer-enhanced ultrafiltration (PEUF) is emerging as a promising process for treatment of water contaminated by toxic metal ions. In PEUF, a water-soluble polymer with strong binding affinity for toxic metal ions is added to contaminated water. The resulting solution is passed through an ultrafiltration (UF) membrane with pore sizes smaller than those of the metal-ion-laden polymer.Highly purified permeates have been obtained using PEUF. This project exploits recent advances in nanoscopic chemistry such as the invention of dendrimers to develop more efficient and cost effective functional materials for PEUF. Dendrimers are highly branched polymers with controlled composition and architecture consisting of three components: a core functionality, interior branch cells, and terminal branch cells. Critical properties of dendrimers such as size, shape, core chemistry, surface chemistry andpolydispersity can be controlled by a judicious choice of synthetic buildingblocks and reaction conditions. For example, the terminal groups of adendrimer can be designed to be compatible or incompatible with a specificsurface, while its core may act as receptor for metal ions. The overallobjective of this project is to evaluate the feasibility of DendrimerEnhanced Ultrafiltration (DEUF) as an efficient, environmentally acceptable,and cost effective process for treating water contaminated by toxic metalions. Commercial dendrimers are being modified chemically to determine the effectiveness of various forms in separating copper, zinc, and cadmium ions. The tendency of the dendrimers to foul UF membranes is also being tested.The Metal Products and Machinery (MP&M) industry is the first target for theapplication of DEUF. Approximately 40,000 of the 70,000 companies ofthe MP & M industry generate wastewater contaminated by toxic metal ions.Under current regulations, the MP& M industry is required to treat its contaminated wastewater prior to discharge into POTWs. EPA is in the process of issuing new and more stringent effluent concentration limitations for the MP&M industry. The additional costs of compliance to these new regulations using the best practicable control technology currently available are estimated to range from 1.95 to 3.59 billiondollars per year. A preliminary evaluation by EPA of the PEUF process showsit to be cost effective compared to chemical precipitation, the wastewatertreatment baseline technology in the MP& P industry. Because the metal-ionbinding capacity of dendrimers is significantly larger than that of linearpolymers currently used in PEUF, the use of DEUF should result in more efficient water purification and significant savings for the MP& M industry.