**Meet the editors**

Michael Schorr Wiener is a professor and doctor honoris causa at the Institute of Engineering, Universidad Autonoma de Baja California, Mexicali, Baja California, México. He has a BSc degree in chemistry and an MSc degree in materials engineering from the Technion-Israel Institute of Technology. He has published 406 scientific and technical articles on materials and corrosion in

English, Spanish, and Hebrew, including books by InTech. He has worked as a corrosion consultant and professor in Israel, the United States, Latin America, Spain, South Africa, and France. He has labored for the phosphoric acid industry in Israel, Europe, Venezuela, and South Africa during 1960–1998 and in Mexico and Brazil during 1998–2015. He is a member of the National System of Researchers in Mexico.

Benjamin Valdez was the director of the Institute of Engineering during 2006–2013, Universidad Autonoma de Baja California, Mexicali, Baja California, México. He has a BSc degree in chemical engineering, has an MSc degree and a PhD degree in chemistry, and is a member of the Mexican Academy of Science and the National System of Researchers in Mexico. He was the guest editor of

Corrosion Reviews, in which he produced two special issues on corrosion control in geothermal plants and the electronic industry. He is a full professor at the University of Baja California. His activities include corrosion research, consultancy, and control in industrial plants and environments. In August 2013, Mexico, he received a "Distinguished Service Award" from NACE International and Mexico Section.

### Contents

### **Preface XI**


Chapter 6 **Phosphate-Based Organic-Inorganic Hybrid Materials: Design, Construction and Technological Applications 121** Hussein M. H. Alhendawi, Ernesto Brunet and Elena Rodríguez-Payán

### Chapter 7 **Purification of Phosphoric Acid by Liquid‐Liquid Equilibrium 143** Khatereh Bahrpaima

### Preface

Chapter 6 **Phosphate-Based Organic-Inorganic Hybrid Materials: Design, Construction and Technological Applications 121**

Chapter 7 **Purification of Phosphoric Acid by Liquid‐Liquid**

Payán

**VI** Contents

**Equilibrium 143** Khatereh Bahrpaima

Hussein M. H. Alhendawi, Ernesto Brunet and Elena Rodríguez-

Phosphoric acid is an important industrial acid that is utilized for manufacturing phosphatic fertilizers and industrial products, for pickling and posterior treatment of steel surfaces to prevent corrosion, for ensuring appropriate paint adhesion, and for the food and beverages industry, e.g., cola-type drinks to impart taste and slight acidity and to avoid iron sedimen‐ tation. A singular application is the manufacture of artificial apatite for coating on stainless steel orthopedic implants in the human body.

Two main processes are used to produce this acid: the wet process PA (WPA) by treatment with H2SO4 and a relatively novel process by treatment with HCl followed by separation of PA applying solvent extraction technology. The composition and purity of the PA obtained by these processes depend upon the mineral and chemical composition of the phosphate rock and the acid used.

The global, economic, and social importance of the phosacid industry is evident by the reali‐ zation of the International Symposium on Innovation and Technology in the Phosphate In‐ dustry, with outstanding success (SYMPHOS, 2013, 2015).

This industry is spread out in countries of four continents—Asia, Africa, America, and Eu‐ rope—which operate mines and production plants and produce fertilizers. Phosacid is one of the most widely known acids. It is used in metallurgy, medicine, dentistry, and cosmetics; as an electrolyte for fuel cells; and as a quality promoter in the food industry.

This volume is well organized displaying the main problems affecting the industry and the solutions proposed in different fields.

In Chapter 1, M. Jamal et al. deal with the thermochemistry and kinetic reaction of apatite with acid solutions. W. Richard et al. explain how alkaline phosphatase is applied for biore‐ mediation of heavy metals from industrial and nuclear wastes in Chapter 2. The theoretical aspects of polysaccharide depolymerization are assessed by J Domingos et al.

M. Schorr and B. Valdez review the world phosphate rock market and the producers in several countries. The environmental problems generated by the phosphoric acid industry in Huelva, Spain, are described by Bolivar et al in Chapter 5. The technological application of phosphatebased materials is presented in Chapter 6. The purification of phosacid is shown in Chapter 7.

This multiauthored book offers a wide spectrum of basic knowledge and practical experience affecting the wide phosphoric acid industry. These learned specialists, producers, and re‐ searchers manifest different approaches and orientation that will be useful for the whole indus‐ try. The global phosacid market and its many phosphate derivatives are expanding worldwide; this trend is expected to continue in the next years, thus producing innovative products.

### **Dr. Michael Schorr Wiener and Dr. Benjamin Valdez Salas**

Institute of Engineering University of Baja California, Mexico

**Section 1**

**Theoretical Aspects**
