This book is intended to serve as a textbook for degree courses in chemical engineering and related disciplines such as petrochemical engineering, biotechnology, safety, and fire engineering. It explains the theory, principles, and applications of mass transfer techniques in detail in a student-friendly manner. It deals with the principles of molecular diffusion, theory of convective and interphase mass transport, the theory and application of the different separation techniques such as gas absorption, distillation, The Solutions Manual of the book (e-version) is available free on the publisher's App CBSiCentral accessible through scratch code provided on the inside front cover of the book.humidification and dehumidification, extraction, leaching, drying, crystallization, and absorption. The book provides a balanced mix of fundamentals and applications. State of-the-art developments and trends in the design and construction of separation equipment and principles of their operation are covered in detail. An exhaustive coverage of the principles and applications of membranes and membrane separations is another highlight of this book. More than 157 worked-out examples, about 660 exercise problems with answers, more than 544 multiple choice questions and answers are included in this book.