Preface

The synthesis and study of clays and clay minerals are some of the widest fields of research in materials science and technology. Characterization and application of many derived clay materials with different polymers and organic and biological molecules are attracting great interest from scientists and researchers, especially with the emergence of nanotechnology. The catalytic behavior of some clay surfaces can change the properties of adsorbed or intercalated molecules. Theoretical approaches using ab initio, quantum chemical, and Monte Carlo calculations combined with new spectroscopic techniques are expanding the knowledge of clay properties. New two-dimensional materials based on clays and clay minerals are attracting attention for their outstanding properties that make them useful as hosts or supporting matrixes in applications such as pharmaceuticals, tissue engineering, environmental remediation, biosensors, filtration, wound dressings, drug delivery, enzyme immobilization, 3D printing, and more. This book is a comprehensive overview of clay science and technology, focusing on synthesis, characterization, simulation, and applications. It is divided into two parts: "Clay Properties and Characterization" and "Clay Properties and Applications."

The first section of the book includes chapters dealing with fundamental properties of clays, their related materials, and characterization techniques.

Chapter 1 reviews studies related to polymer–clay materials with emphasis on the use of molecular and vibrational spectroscopies in the characterization of conducting polymer-clay nanocomposites.

Chapter 2 reviews fundamental concepts related to clay structure and properties. It also discusses reasons to use clay in hybrid materials.

Chapter 3 focuses on the thermodynamics and kinetics of removing copper (II) and methyl orange from an aqueous solution using natural clay and its composites.

Chapter 4 presents the chemical, mineralogical, and rheological characterization of samples from four clay deposits before and after fractionation. These raw clays are used in the production of ceramic tiles, bricks, blocks, and artisanal pieces in Sergipe, Brazil, for possible use in high value-added products such as cosmetics and pharmaceuticals.

Chapter 5 examines one-dimensional natural clay decorated with magnetic nanoparticles of Fe3O4. The material is well characterized by different physicalchemical techniques. The chapter shows that the functionalization of one-dimensional clay minerals has potential applications in display devices, photonic switches, and other applications.

The second section of the book includes chapters dealing with applications of clays and their related materials.

Chapter 6 discusses the use of bentonite clay in the recovery of copper metal atoms from printed circuit boards (from electronic waste). The recovery process is optimized by several parameters, and this chapter proposes an eco-friendly way to recover copper ions with no environmental issues.

Chapter 7 examines the effect of the addition of two types of wastes on the technological properties of fired brick-based yellow clay. The test results indicate that the addition of wastes to clay bricks improves their technological properties and highlights the possibility of waste reuse in a safe and sustainable way.

Chapter 8 discusses the thermal behavior of geopolymers, which can be changed by clay and alkali compositions. The chapter shows that geopolymers can be used as fire-resistant materials.

Chapter 9 reviews the thermal activation of clays to produce an extraordinarily high-quality supplementary cementitious material (SCM) based on the contents of its hydraulic factors: reactive silica (SiO2r–) and reactive alumina (Al2O3r–). The production process and the optimization of its use in the new types of cement offer better performance, features, and durability.

Chapter 10 considers the production of electric porcelain insulators utilizing local raw materials from developing countries. The raw materials used include feldspar, quartz/silica, and kaolin. The chapter concludes that standard and acceptable electric porcelain insulators can be produced from local raw materials.

Chapter 11 discusses the physical-chemical characterization of titania-pillared clay hybrid membranes. The developed membranes can be used to remove heavy metal ions from wastewater, the recovery of which yields maximum benefit. The product presented can best treat textile effluent from the dye industry with concentrations in the range of 50 ppm.

Even though knowledge of the real impact of materials derived from clay on the environment, industrial processes, and human health is still limited, I hope that this book will prove useful for understanding the broad and complex field of clay science and technology. Finally, I would like to thank all the contributing authors as well as the staff at IntechOpen for their efforts and support throughout the publishing process.

> **Dr. Gustavo Morari do Nascimento** Professor, Centre for Natural Sciences and Humanities, Federal University of ABC, Santo André, Brazil

Section 1
