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).

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.

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).

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.