Metals Removal Via Spouted Bed Electrolytic Reactors

在2003年CERCLA公布的275种物质中，包括了所有的重金属。因此，有效修复受污染的场地以供再利用，必须始终解决有效地从固体材料和地下水中去除重金属的问题。该项目的目标是开发两种新的污染场地异地修复技术，其基础是应用喷动床颗粒电极去除污染水域中的重金属：(1)电积金属和金属混合物的喷动床电解回收(SBER)；(2)喷动床电解回收 用于电辅助吸附某些重金属化合物的床电吸附/解吸(SBED)，通过增加其容量和污染物清除率来提高活性碳吸附剂的使用效率，从而减少对吸附剂的需求，并降低当前的热再生成本。这一目标将通过实现以下具体目标来实现：具体目标1：将建设和开发两个新的喷动床槽系统：一个用于金属电积(喷动床电解回收，SBER)，另一个用于在活性碳吸附材料上电吸附/解吸重金属化合物(喷动床电吸附/解吸，SBED)。具体目标2：SBER将被用来研究和开发有效的方法，在同一装置中从溶液中高速回收多种金属。这种方法将包括研究单个金属的电化学和从选定的四种(Cd、Cr、Cu和Ni)单个金属中回收，依次形成二元、三元和四元混合物。这还将涉及采用新技术，例如电解回收与“过程中沉淀”相结合，以获得高回收率。具体目标3：将使用SBED系统来研究和开发某些重金属(As和Hg)化合物的电辅助吸附的有效方法，以提高受污染水的去除率， 并降低目前活性碳吸附剂热再生的成本。 具体目标4：基于现有的流体力学模型以及从任务1、2和3获得的流体力学和电化学数据，将开发SBER和SBED系统的数值模型，并用于探索实验室系统到操作规模系统的放大策略。具体目标5.该项目的最终结果将侧重于从从地下水和/或含有金属混合物的受污染土壤的淋滤中获得的受污染场地的样品中回收选定的金属。具体的来源将根据我们SBRP和RIDEM的人工建议来确定。

Among the 275 substances on 2003 CERCLA Priority List of Hazardous Substances are included all the heavy metals. Thus, the effective remediation of contaminated sites for reuse must invariably address the efficient removal of heavy metals from solid materials and groundwater. The goal of this project is the development of two new ex-situ remediation technologies for contaminated sites, based on the application of spouted bed particulate electrodes to the removal of heavy metals from contaminated waters: (1) Spouted Bed Electrolytic Recovery (SBER) for electrowinning metals and metal mixtures; and (2) Spouted Bed Electrosorption/Desorption (SBED) for the electro-assisted adsorption of certain heavy metal compounds to improve the effectiveness of the use of activated carbon adsorbents by increasing their capacity and contaminant removal rates, so that less adsorbent is needed, and to reduce the current costs of thermal regeneration. This goal will be achieved by fulfilling the following Specific Aims: Specific Aim 1: Two new spouted bed cell systems will be constructed and developed: one for metal electrowinning (Spouted Bed Electrolytic Recovery, SBER), and the other for electrosorption/desorption of heavy metal compounds on activated carbon adsorbents (Spouted Bed Electrosorption/Desorption, SBED). Specific Aim 2: The SBER will be used to investigate and develop effective methods to recover multiple metals from solutions at high rates in the same device. This approach here will involve investigation of the electrochemistry and recovery of individual metals from a selected set of four (Cd, Cr, Cu and Ni) individual metals, successively building up to binary, ternary, and finally quaternary mixtures. This will also involve adaptation of new techniques, such as electrolytic recovery coupled with "in-process precipitation" for high recovery rates. Specific Aim 3: The SBED system will be used to investigate and develop effective methods for the electro-assisted adsorption of certain heavy metal (As and Hg) compounds to improve removal rates from contaminated water, and to reduce the current costs of thermal regeneration of activated carbon adsorbents. Specific Aim 4: Numerical models of SBER and SBED systems, based on existing hydrodynamic models, and hydrodynamic and electrochemical data obtained from Tasks 1, 2, and 3 will be developed and used to explore scale-up strategies of laboratory systems to operating-scale systems. Specific Aim 5. The culmination of the project will focus on recovery of selected metals from samples from contaminated sites obtained from groundwater and/or by leaching of contaminated soils containing mixtures of metals. Specific sources will be identified based uoon recommendations from oarticioants in our SBRP and RIDEM.