Separations Technology最新文献_第2页

Design of combined membrane and distillation processes 膜蒸馏联合工艺设计

Separations Technology Pub Date : 1996-07-01 DOI: 10.1016/0956-9618(96)00151-8

Torbjørn Pettersen , Andrew Argo , Richard D. Noble , Carl A. Koval

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引用次数: 42

Adsorption and separation of β, β-dimethylnaphthalene isomers on various large-pore zeolites having 12-oxygen-member-ring structure β， β-二甲基萘异构体在12-氧元环结构大孔沸石上的吸附与分离

Separations Technology Pub Date : 1996-07-01 DOI: 10.1016/0956-9618(96)00152-X

S.B. Pu, Y. Tanaka, T. Inui

引用次数: 6

Displacement washing of lime mud: tailing effects 石灰泥浆置换洗涤:尾矿效应

Separations Technology Pub Date : 1996-07-01 DOI: 10.1016/0956-9618(96)00154-3

Gunnar Eriksson, Anders Rasmuson, Hans Theliander

引用次数: 14

Crystal growth of thiourea adducts with cyclohexane-methylcyclopentane mixture 环己烷-甲基环戊烷混合物中硫脲加合物的结晶生长

Separations Technology Pub Date : 1996-07-01 DOI: 10.1016/0956-9618(96)00156-7

Kwang-Joo Kim , Jung-Min Lee , Seung-Kon Ryu

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引用次数: 1

Special issue: separations in environmental systems 特刊:环境系统中的分离

Separations Technology Pub Date : 1996-04-01 DOI: 10.1016/S0956-9618(96)90005-3

Sotira Yiacoumi (Guest Editor)

引用次数: 0

Efficient separation and recovery of technetium-99 from contaminated groundwater 从污染地下水中高效分离和回收锝-99

Separations Technology Pub Date : 1996-04-01 DOI: 10.1016/0956-9618(96)00147-6

Baohua Gu , Kathryn E. Dowlen , Liyuan Liang , Jay L. Clausen

{"title":"Efficient separation and recovery of technetium-99 from contaminated groundwater","authors":"Baohua Gu , Kathryn E. Dowlen , Liyuan Liang , Jay L. Clausen","doi":"10.1016/0956-9618(96)00147-6","DOIUrl":"10.1016/0956-9618(96)00147-6","url":null,"abstract":"<div>This work reports a new approach that can effectively separate and recover Tc (as pertechnetate, TcO4−) from contaminated groundwater. Activated carbon was used in both batch adsorption and column leaching studies. The adsorption experiments indicated that activated carbon adsorbs TcO4− selectively and effectivele over a wide range of pH values and from various dilute electrolyte solutions (< 0.01 M). The partitioning coefficient (Kd) of TcO4− exceeded 27 000 ml/g when actual groundwater was used, and exceeded 12000 ml/g when background solutions of 0.01 M CaCl2 and Na2SO4 were used. TcO4− removal efficiency was > 99% under these conditions, except in a 0.01 M NaNO3 background solution. Column studies confirmed a high adsorption capacity and selectivity of activated carbon for TcO4−. Within the detection limit, no Tc breakthrough was observed when more than 14000 pore volumes of contaminated groundwater (containing ∼3000 pCi Tc/1) were passed through a small column (6.6 × 30 mm) with 0.5 g activated carbon. Recovery of TcO4− from activated carbon was studied using various chemical reagents such as salicylate, phthalate, NaNO3, NaCl, and Na2SO4. Salicylate was found to be the most effective in desorbing and recovering the adsorbed TcO4− (as high as 100%). Therefore, the spent carbon can be disposed as low-level radioactive wastes or may be regenerated. Results of this work suggest that the use of activated carbon to remediate Tc-contaminated groundwater can be a promising technology — it is cost-effective and requires minimal installation and maintenance during the pump-and-treat processes.</div>","PeriodicalId":101160,"journal":{"name":"Separations Technology","volume":"6 2","pages":"Pages 123-132"},"PeriodicalIF":0.0,"publicationDate":"1996-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0956-9618(96)00147-6","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77581659","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 61

Equilibrium and kinetic studies of copper adsorption by activated carbon 活性炭吸附铜的平衡及动力学研究

Separations Technology Pub Date : 1996-04-01 DOI: 10.1016/0956-9618(96)00146-4

Jiaping Chen, Sotira Yiacoumi, Timothy G. Blaydes

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引用次数: 65

Design equations for soil aeration via bioventing 通过生物通风设计土壤通气方程

Separations Technology Pub Date : 1996-04-01 DOI: 10.1016/0956-9618(96)00144-0

David W. DePaoli

引用次数: 5

Removal of technetium-99 from contaminated groundwater with sorbents and reductive materials 用吸附剂和还原性材料从污染地下水中去除锝-99

Separations Technology Pub Date : 1996-04-01 DOI: 10.1016/0956-9618(96)00148-8

Liyuan Liang, Baohua Gu, Xiangping Yin

{"title":"Removal of technetium-99 from contaminated groundwater with sorbents and reductive materials","authors":"Liyuan Liang, Baohua Gu, Xiangping Yin","doi":"10.1016/0956-9618(96)00148-8","DOIUrl":"10.1016/0956-9618(96)00148-8","url":null,"abstract":"<div>Pertechnetate oxyanion (TcO4−), which is highly soluble in water and readily mobile in the environment, can be immobilized through an ion exchange /adsorption process and chemical reduction followed by adsorption and/or precipitation. Previous studies have focused on the separation and removal of 99TcO4− from high-level waste streams; however, little information is available for 99TcO4− removal from only slightly contaminated groundwater. This paper describes treatment of 99TcO4−-contaminated groundwater with both batch and column flowthrough experiments. Synthetic resins and sponges, and zero-valence iron filings were used to evaluate their capacities and the rates of 99TcO4− removal. The toxicity characteristic leaching procedure (TCLP) was applied to evaluate the leachability of 99Tc adsorbed or co-precipitated on iron. Results suggest that both iron and synthetic resins remove 99TcO4− from groundwater and that at a high flow rate (with residence time of less than 1 min), 99TcO4− removal capacity is greater for iron filings than for the synthetic resins on a volume basis. Additionally, the rate of 99TcO4− sorption on the sponge is slow (approximately 3 days), and the capacity is relatively low. No appreciable amount of 99Tc can be leached out from the spent iron filings by the TCLP test. Overall, zero-valence iron filings provide fast reaction and high removal capacity for 99TcO4− in groundwater. The high removal efficiency, low cost, and the small waste production of zero-valence iron are attractive for remediation of 99TcO4−-contaminated groundwater.</div>","PeriodicalId":101160,"journal":{"name":"Separations Technology","volume":"6 2","pages":"Pages 111-122"},"PeriodicalIF":0.0,"publicationDate":"1996-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0956-9618(96)00148-8","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82943580","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 85

Biological activated carbon treatment of effluent water from wastewater treatment processes of plating industries 生物活性炭处理电镀工业废水的研究

Separations Technology Pub Date : 1996-04-01 DOI: 10.1016/0956-9618(96)00150-6

Yoshitake Suzuki , Kazuhiro Mochidzuki , Yasushi Takeuchi , Yoshiteru Yagishita , Tadashi Fukuda , Hideo Amakusa , Hiroshi Abe

引用次数: 18