This book is a comprehensive introduction to the principles of mass transfer and their applications to major separation processes. Presenting sufficient theory and design fundamentals to ensure a sound understanding of basic concepts, this clearly written and well-organized text is suitable for courses in Mass Transfer, Separation Processes, Transport Processes, and Unit Operations offered to undergraduate students in chemical engineering. It will also be useful to postgraduate students of chemical engineering, students of allied disciplines, and practising engineers. Progressive in approach, the phenomenon of diffusion and the concept of mass transfer coefficient have been elucidated by drawing numerous examples from diverse areas. Separation processes relevant to chemical and allied industries have been discussed in considerable depth, and the design methodologies have been illustrated. Adequate emphasis has been placed on practical applications. Details of construction and operation of various separation equipment including recent developments have been explained. The book has about one hundred and fifty solved problemsand over three hundred exercise problems, many of which directly pertain to process industries. In addition, over five hundred short and multiple choice questions have been designed to stimulate students’ understanding.