The modern developments of the CRT theory are described and extensively documented. For practical application, these models are categorized and evaluated. The models of catalysis and diffusion phenomena are treated in detail, particularly in porous media such as zeolites, clays, and nanotubes. Modern theoretical methods such as molecular dynamics, Monte Carlo, and quantum chemistry are presented. Adsorption and desorption in catalysis are thoroughly described both theoretically and experimentally. Additionally, the existing literature is comprehensively addressed and evaluated. Thus, the book provides a very comprehensive representation of the current status, serving as an introduction and overview for engineers and scientists in research, development, and education in chemistry, chemical engineering/process engineering, and related fields.