Separations Technology最新文献_第3页

Estimating internal mass transfer rates in soils using scintillation fluid extraction 用闪烁流体萃取法估算土壤内部传质速率

Separations Technology Pub Date : 1996-04-01 DOI: 10.1016/0956-9618(96)00145-2

Thomas C. Harmon , Brian K. Dela Barre , Paul V. Roberts

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引用次数: 2

Thermodynamics and kinetics of adsorption in the presence of geometric roughness 几何粗糙度下吸附的热力学和动力学

Separations Technology Pub Date : 1996-04-01 DOI: 10.1016/0956-9618(96)00149-X

Massimiliano Giona , Manuela Giustiniani

引用次数: 5

Analysis of the sodium lactate concentration process by electrodialysis 电渗析乳酸钠浓缩过程分析

Separations Technology Pub Date : 1996-02-01 DOI: 10.1016/0956-9618(96)00139-7

Nicoletta Boniardi, Renato Rota, Giuseppe Nano, Bruno Mazza

引用次数: 30

Recovery of cationic surfactant by using precipitation method 沉淀法回收阳离子表面活性剂

Separations Technology Pub Date : 1996-02-01 DOI: 10.1016/0956-9618(95)00131-X

A.K. Vanjara, S.G. Dixit

引用次数: 17

Separating oil from oil-water emulsions by electroflotation technique 电浮法分离油水乳状液中的油

Separations Technology Pub Date : 1996-02-01 DOI: 10.1016/0956-9618(95)00136-0

Ashraf Y. Hosny

{"title":"Separating oil from oil-water emulsions by electroflotation technique","authors":"Ashraf Y. Hosny","doi":"10.1016/0956-9618(95)00136-0","DOIUrl":"10.1016/0956-9618(95)00136-0","url":null,"abstract":"<div>The separation of finely dispersed oil from oil-water emulsions was carried out in an electroflotation cell which has a set of electrodes, a lead anode and stainless steel screen cathode. The effect of operating parameters on the performance of the batch cell was examined. The parameters investigated are electrical current, oil concentration, flotation time and flocculant agent concentrations. A well-fitted empirical correlation represents the change in percentage oil removal with wide range of operating conditions was obtained. The oil separation reached 65% at optimum conditions; 75% in the presence of NaCl (3.5% by wt. of solution); and 92% with the presence of NaCl and at optimum concentration of flocculant agent. Electrical energy consumption varied from 0.5 to 10.6 KWh/m3 according to experimental conditions. An equation relates the K with I was obtained. The general form of the equation is K = constant (I)n; where the n values are 0.6 4 and 0.62 for solutions with and without NaCl, respectively. The previous relation is valid only for current values from 0.3 to 1.2 A. The effect of emulsion flow rate on the separation process was determined on continuous scale.</div>","PeriodicalId":101160,"journal":{"name":"Separations Technology","volume":"6 1","pages":"Pages 9-17"},"PeriodicalIF":0.0,"publicationDate":"1996-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0956-9618(95)00136-0","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85419282","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: 137

Modelling of filtration processes of fibrous filter media 纤维过滤介质过滤过程的建模

Separations Technology Pub Date : 1996-02-01 DOI: 10.1016/0956-9618(96)00140-3

Jorge A. Destephen, Kyung-Ju Choi

{"title":"Modelling of filtration processes of fibrous filter media","authors":"Jorge A. Destephen, Kyung-Ju Choi","doi":"10.1016/0956-9618(96)00140-3","DOIUrl":"10.1016/0956-9618(96)00140-3","url":null,"abstract":"<div>This work presents a stochastic approach, based on Monte Carlo method, to simulate liquid filtration processes through non-woven fibrous materials. The real filter material is represented as a multilayer medium with a network of multiply connected pores. To describe the deposition and resuspension of particles on and from the filter medium, the following four mechanisms were considered: particle capture by sieving, patricle capture by fibers; particle capture by blocked pores; and particle re-entrainment. The particle capture by fibers and blocked pores, and particle re-entrainment depend on the balance between the adhesion and removal forces. The adhesion forces for particles of diameter smaller than 20 μm were determined through the concept of London-Van Der Waals forces. For particles of diameter greater than 20 μm, gravitational forces were considered. Three-dimensional random flow was assumed to stimulate the particles motion through the multilayer medium. The pressure drop across the filter medium was calculated as the sum of the pressure drop across the clean filter plus the pressure drop due to the deposited particles.A FORTRAN Program was developed to implement the filtration process model. For a wide range of typical filtration conditions, the calculated filter efficiencies predicted the experimental results with a percent difference between 0.5 and 19.3 depending on the particle size. The filter material capacities were predicted with an average discrepancy of 23.0%</div>","PeriodicalId":101160,"journal":{"name":"Separations Technology","volume":"6 1","pages":"Pages 55-67"},"PeriodicalIF":0.0,"publicationDate":"1996-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0956-9618(96)00140-3","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85359250","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: 28

Synthesis of anion exchange adsorbent particles by surface functionalization of polystyrene-divinylbenzene based spherical porous matrices 聚苯二乙烯基球形多孔基质表面功能化合成阴离子交换吸附剂颗粒

Separations Technology Pub Date : 1996-02-01 DOI: 10.1016/0956-9618(96)00142-7

A. Tongta , A.I. Liapis , S. Hagen

{"title":"Synthesis of anion exchange adsorbent particles by surface functionalization of polystyrene-divinylbenzene based spherical porous matrices","authors":"A. Tongta , A.I. Liapis , S. Hagen","doi":"10.1016/0956-9618(96)00142-7","DOIUrl":"10.1016/0956-9618(96)00142-7","url":null,"abstract":"<div>The replacement of Br− by trimethylamine for the synthesis of anion exchange adsorbent particles by surface functionalization of polystyrene-divinylbenzene based spherical porous particles was studied experimentally and theoretically. The calculated values of the kinetic parameters indicate that the net rate of the replacement of Br− by trimethylamine is dominated by the kinetic mechanism involving the formation and opening of an epoxide, <figure><img></figure> where P represents the polymeric backbone. The theoretical results obtained from the solution of the equations of the mathematical model that describes the dynamic behavior of the kinetic mechanisms, clearly indicate that the highest concentration of the desired product, <figure><img></figure> on the surface of the pores of the particles, is obtained when the initial concentration of trimethylamine is highest. The equilibrium adsorption of bovine serum albumin (BSA) into the anion exchange adsorbent particles produced in this work was also studied, and the results indicate that the maximum value of the concentration of BSA in the adsorbed phase is a weak function of the concentration of the desired product, <figure><img></figure>, on the surface of the pores of the particles.</div>","PeriodicalId":101160,"journal":{"name":"Separations Technology","volume":"6 1","pages":"Pages 77-89"},"PeriodicalIF":0.0,"publicationDate":"1996-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/0956-9618(96)00142-7","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77412869","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: 0

Modelling studies on the transient and steady state behaviour of a simulated counter-current chromatographic system 模拟逆流色谱系统瞬态和稳态行为的模型研究

Separations Technology Pub Date : 1996-02-01 DOI: 10.1016/0956-9618(95)00138-7

Bee-Gim Lim, Chi-Bun Ching

引用次数: 13

Optimization of continuous countercurrent adsorption systems 连续逆流吸附系统的优化

Separations Technology Pub Date : 1996-02-01 DOI: 10.1016/0956-9618(95)00137-9

M.M. Hassan, K.F. Loughlin, M.E. Biswas

引用次数: 4

Recovery of carboxylic acids, C2C6, from an aqueous waste stream using tributylphosphate (TBP): Effect of presence of inorganic acids and their sodium salts 用磷酸三丁酯(TBP)从含水废水中回收羧酸C2C6:无机酸及其钠盐存在的影响

Separations Technology Pub Date : 1996-02-01 DOI: 10.1016/0956-9618(95)00132-8

M.N. Ingale, V.V. Mahajani

引用次数: 42