This book focuses on lignin biorefinery, with special emphasis on lignin extraction, its chemical structure, depolymerization and degradation techniques, and its applications in the production of green industrial products. It provides an overview of lignin chemistry and biorefinery processes, as well as the potential of lignin in the synthesis of industrial chemicals. This book covers pretreatment methods for lignocellulosic biomass using various extraction techniques and includes the chemical analysis of lignin structures obtained from different methods. It also explains the catalytic valorization of lignin and its biological degradation processes. Key features:Covers the latest lignin extraction and valorization technologies. Provides updated information on pretreatment technologies for lignin synthesis from biomass. Provides insights into the conversion of depolymerized lignin into biopolymers, resins, and other high-value products. Discusses the exploration of lignin-based modern medicines and smart nano-biomaterials. Provides a discussion of the environmental and market impacts of lignin-based biorefinery. This book is intended for researchers and graduate students in chemical engineering, lignin chemistry, and bioresource engineering.