Adsorption processes have experienced a significant growth in the last decades. This growth was a result of scientific and technological advances which generated new adsorbents as well as new concepts for processing systems (UOP's "Sorbex" process and PSA cycles). The expectations for a continued development of adsorption are high since process engineering is deeply concerned with intensive processes using less energy. Adsorption processes are also relevant to the increasingly important area of biotechonology. The development of affinity processes is a creative synthesis of biochemistry, molecular biology and chemical engineering. This NATO Advanced Study Institute on "ADSORPTION: SCIENCE and TECHNOLOGY" had as a primary objective to provide an updated treatment of the fundamentals of adsorption and adsorption processes. The lectures presented at the Institute are collected in this volume together with a few papers presented by participants. The material is arranged in four sections.Part I deals with the characterization of adsorption and thermodynamics of adsorption, namely the correlation of equilibrium data.Part II covers the kinetics of adsorption and fixed-bed processes (equilibrium theory, design aspects, adsorptive reactors).Part III is an extensive coverage of cyclic processes (pressure swing adsorption and thermal swing adsorption) and simulated moving beds (modeling for process optimization and industrial applications).Finally Part IV deals with applications mainly in biotechnolo gy (con tin uous adsorption, affini ty chrom atography, gel permeation, chromatographic reactors, scale-up methods).

Multiphase reactors are becoming an important subject as a result of numerous applications in various fields ranging from chemical and petrochemical to food, biological and pharmaceutical (FBPl en gineering, namely in the hydrodesulfurization of petroleum, produc tion of antibiotics and wastewater treatment. The importance of the subject is measured by the increasing num ber of publications and meeting sections dedicated to it. Therefore an Advanced Study Institute on Multiphase Chemical Reactors was held in Vimeiro, Portugal from 18 to 30 August 1980, following an International Symposium on Chemical Engineering of Gas-Liquid-Solid Catalyst Reactions, held in Liege, 1978. The purpose of this NATO ASI was to present a didacted approach to multiphase reactor design, through the interaction among hydro dynamics, reaction and transport processes. The lectures delivered there are compiled in two volumes. In the first volume an overview of the field is presented, followed by a detailed analysis of the fundamental concepts (interphase mass transfer models, mass transfer with chemical reaction, theory of residence time distributions and micromixing phenomenal.Numerical methods are often required to solve the mathematical models involved; so a chapter is dedicated to this subject followed by a discussion of steady-state multiplicity and stability. Finally, a section with special applications of multiphase reactors is included, presenting topics on biological reactors, emulsion po lymerization, supported liquid phase catalyst and enhanced oil re- VI covery."

In a general way, "percolation" might be defined as a process in which at least two phases, one continuous and the other dispersed, are in bulk relative movement and exchange heat and/or mass through their interface. In practical terms this covers operations such as adsorption, ion exchange, leaching, washing, fluid-fluid displacement in po rous media, deep bed filtration, chromatography. Apart from the fact that the design of these processes is almost empirical we have concluded to the necessity of organizing a Summer School on this topic because 1. Powerful new concepts have emerged in this area in the last decade, centered around unsteady-state, non-linearly coupled, multi component systems, and low energy processes 2. There is, potentially, a phenomenologythat is common to all percolation operations, and which even extends to other mi gration phenomena such as electrophoresis, sedimentation, traffic flow 3. There is a need for a synthetic and didatic approach to these problems and its spreading will be most fruitful for the de velopment of separation science. We have tried to choose lecturers who have, themselves, ma de significant contributions toward the development of such an approach. The lectures given at the Summer School held at Espinho, Portugal in July 17-29, 1978 were compiled in this volume. It is VI divided in three parts. In the first part some general and intro ductory notions common to all operations are presented and chroma tography is analised in detail."

Ion exchangeis a field in which cooperation betweenchemists and chemical engineersis highlydesirable. This NATO AdvancedStudy Institute had as aprimary objectiveto bring together chemists and chemical engineers. The Institute was dedicatedto the memory of Prof. Ted Vermeulen who was supposed to be our scientificadvisor. The lectures presentedat the Institute are collected in this volume together with papers presentedby F.Evangel ista, A.Bungeand G.Grevillot. The materialis arrangedin five sections. The Introduction con tains a review of the contributions of Vermeulen'swork to the field and an overviewof ion exchange. Section2 deals with the chemistry of ion exchangeresins.Section3 covers the chemical engineeringas pects of ion exchangeprocesses (thermodynamics, kinetics, modelling and modes of operation).Section 4 starts with a broad review of in dustrial applicationsof ion exchangefollowed by papers dealing with hydrometallurgy, react ion processes involvingion exchangers and zeolites.Finally section5 deals with Alternative Processes to ion exchange.Itincludesion exchangemembranes, solvent extraction, liquidmembranes andcementation. I am very grateful to my coworkerJ .Loureirofor the collabora tion as Institute Secretary. Cooperationof M.Hudson at severalsta ges of the organization of the Institute is gratefully acknowledged. The financialsupport of the NATO AdvancedStudy Institute Pro gramme made this course possible.The participants made it allworth while. October1,1985 A.E.Rodrigues VII NATO Advanced Stud y Institute "Ion Exchange: Science and Technology" Director: A.E.Rodrigues Advisory Committee: M.Hudson (co-director), M.Streatand D.Tondeur Lecturers: S.Carra, Politecnico Milano, Italy C.Costa, Universidade do Porto, Portugal P .Grammont, Duolite International, France F.Helfferich, Penn.State University, USA M.Hudson, University of Reading, UK ."

Adsorption processes have experienced a significant growth in the last decades. This growth was a result of scientific and technological advances which generated new adsorbents as well as new concepts for processing systems (UOP's "Sorbex" process and PSA cycles). The expectations for a continued development of adsorption are high since process engineering is deeply concerned with intensive processes using less energy. Adsorption processes are also relevant to the increasingly important area of biotechonology. The development of affinity processes is a creative synthesis of biochemistry, molecular biology and chemical engineering. This NATO Advanced Study Institute on "ADSORPTION: SCIENCE and TECHNOLOGY" had as a primary objective to provide an updated treatment of the fundamentals of adsorption and adsorption processes. The lectures presented at the Institute are collected in this volume together with a few papers presented by participants. The material is arranged in four sections.Part I deals with the characterization of adsorption and thermodynamics of adsorption, namely the correlation of equilibrium data.Part II covers the kinetics of adsorption and fixed-bed processes (equilibrium theory, design aspects, adsorptive reactors).Part III is an extensive coverage of cyclic processes (pressure swing adsorption and thermal swing adsorption) and simulated moving beds (modeling for process optimization and industrial applications).Finally Part IV deals with applications mainly in biotechnolo gy (con tin uous adsorption, affini ty chrom atography, gel permeation, chromatographic reactors, scale-up methods).