Development of Surfactant Application in Wastewater Treatment

Abstract

Water is the most important and essential component for the existing activities of human beings, animals and plants. It is estimated that the total amount of water on the earth is about 1.3 billion tons, but 97% of that is salty ocean water and not suitable for drinking. With the rapid growth of population, industrialization and agricultural modernization and other geological and environmental changes, the water environment is deteriorating continuously. Water pollution and water shortage are two of the most important environmental problems in the world. Consequently, water pollution has become a critical issue in recent years. Pollutants in wastewater include organic, inorganic, biological compounds. As many of them have serious toxicity and even show carcinogenic, the release of considerable amount of wastewater into environment causes damages to human being and aquatic conditions, and further leads to the shortage of water resources. Therefore, the need for wastewater treatment in a low-cost, safe and efficient way and improving the reuse efficiency of water resources have become a must. In recent years, surfactant-based separation techniques have made a great progress in industrial and analytical areas. It offers many advantages including low-energy consumption and environment protection, and has been proved efficient in the separation of many inorganic and organic pollutants. To enhance the application of surfactant-based separation techniques in wastewater treatment, it is very important to have a better understanding of the mechanisms involved in this process. The mechanism and development of surfactant-based wastewater treatment techniques, including micelle-enhanced ultrafiltration (MEUF), surfactant-modified solid phase adsorption and surfactant-based liquid-liquid phase separation are summarized. The effects of the surfactant characteristics, the chemistry of the pollutants and the solution conditions used in experiments on the extract kinetics and efficiencies are discussed. This review aims to provide reference and inspiration for researchers and promote the development of wastewater treatment technologies.