This book consists of 8 chapters on the latest advances in chemistry research. Chapter 1 is devoted to the state-of-the art catalysts for pyrolysis to obtain biofuels and chemicals from biomass, plastics and other residues. The studies catalysts are critically revised, focusing on the most promising solids and their improvements using bifunctional catalysts. In addition, guidance on their future perspectives is discussed. Chapter Two focuses on a general approach to the various sulfides on the occurrence of sulfites and the methods usually used to monitor and warn about possible adverse reactions resulting from their use in food products. A case study of sulfites in meat preparations is also presented. In Chapter 3, the authors considered the methods available in literature on the synthesis of apatite-structured compounds. Chapter 4 focuses on the magnetic torque inside the superoxide radical as the driving force for oxygen activation by cofactor-free dioxygenases. In Chapter 5, the developments in covalent organic frameworks membranes over the past few years are reviewed. The fabrication methods of COF membranes, including bottom-up strategy and top-down strategy are discussed and the applications of COF membranes in liquid separation are highlighted. Finally, the existing challenges and outlook in this field are analyzed. Chapter 6 reviews various eco-friendly green and one-pot synthetic approaches useful in preparing 1,2,4-thiadiazole containing derivatives. Chapter 7 gives brief details on the chemistry, physicochemical properties, clinical uses, and chemical and photodegradation of 5-fluorouracil (5-FU), an anticancerous agent which is widely used in the treatment of different malignancies including stomach cancer, head and neck cancer, and breast cancer. The last chapter of this volume collectively describes the recent important catalytic roles of manganese Schiff base catalysts. The role of Mn-Schiff base complexes in biological activities is also examined.