Preface

Colloids are types of mixtures in which a microscopic substance is dispersed throughout a dispersion medium. The particles of the dispersed phase have a diameter of 1–1000 nanometers.

The most common phenomena of colloids in the ecosystem appear in the blue color of the sky, which is due to the scattering of light by colloidal particles in the air, known as the Tyndall effect. In our body, blood is a colloidal solution. Other examples include milk, cream, gelatin, jelly, colored glass, river mud, and butter.

Colloids and colloidal systems are useful in human health as well as commercial and industrial situations. The important applications of colloids are in medicines, sewage disposal, water purification, formation of the delta, cleansing action of soap, industry, mining, smoke precipitation, photography, electroplating, agriculture, rubber industry, artificial rain, and more.

Colloids - Types, Preparation and Applications deals with several aspects of colloid morphology, synthesis, and applications. It gathers recent research by outstanding experts in the field of colloids, including research into colloid synthesis, modification, and applications.

The book includes twelve chapters divided into three sections. The first section includes four chapters that discuss different techniques for synthesizing colloids: Chapter 1, "Optimization of Biogenic Synthesis of Colloidal Metal Nanoparticles"; Chapter 2, "Recent Progress in the Electrochemical Exfoliation of Colloidal Graphene: A Review"; Chapter 3, "A Simple and "Green" Technique to Synthesize Metal Nanocolloids by Ultrashort Light Pulses"; and Chapter 4 "Gemini Imidazolinium Surfactants: A Versatile Class of Molecules". The second section includes three chapters that explain the structure, dynamic and stability of colloids: Chapter 5, "Aerogels Utilization in Electrochemical Capacitors"; Chapter 6, "Structure and Dynamics of Aqueous Dispersions"; and Chapter 7, "Colloidal Stability of Cellulose Suspensions" The third section includes five chapters that discuss applications of colloidal particles: Chapter 8, "Removal of Copper Ions from Aqueous Solution Using Liquid Surfactant Membrane Technique"; Chapter 9 "Hydrocolloids in Dentistry: A Review"; Chapter 10, "Application of Colloids and Its Relevance in Mineral Engineering"; Chapter 11 "Magnetic Iron Oxide Colloids for Environmental Applications"; and Chapter 12, "Colloidal Nanocrystal-Based Electrocatalysts for Combating Environmental Problems and Energy Crisis".

I would like to express our sincere thanks to Dr. Haiam Morsy Aboul-Ela, Marine Biotechnology and Natural Products Lab, the National Institute of Oceanography and Fisheries, Alexandria branch, Egypt; Dr. Radwa El-Salamony, Egyptian Petroleum Research Institute; and Dr. Khalid ElWakeel, Faculty of Science, Port Said University, Egypt for their contributions in the scientific revision of the book chapters.

**II**

**Section 3**

Membrane Technique

Application of Colloidal Particles **133**

**Chapter 8 135**

**Chapter 9 147**

**Chapter 10 155**

**Chapter 11 165**

**Chapter 12 191**

Colloidal Nanocrystal-Based Electrocatalysts for Combating Environmental

*by Roshan Nazir, Abhay Prasad, Ashish Parihar, Mohammed S. Alqahtani* 

Removal of Copper Ions from Aqueous Solution Using Liquid Surfactant

*by Huda M. Salman and Ahmed Abed Mohammed*

*by Stanley Onwubu and Chibuzor Stellamaris Okonkwo*

*by Abhyarthana Pattanaik and Rayasam Venugopal*

*María del Puerto Morales and Jesús G. Ovejero*

Problems and Energy Crisis

*and Rabbani Syed*

Application of Colloids and Its Relevance in Mineral Engineering

Magnetic Iron Oxide Colloids for Environmental Applications *by Alvaro Gallo-Cordova, Daniela Almeida Streitwieser,* 

Hydrocolloids in Dentistry: A Review

I would also like to express my thanks to IntechOpen Author Service Manager Ms. Kristina Kardum Cvitan. I am also grateful to the book authors for their hard work and worthy contributions.
