Chapter 19 - Polymeric supports for water treatment applications

Abstract

The development of industry and urbanization caused the improvement of the quality of life and civilization. Over time, it also increased pollution and various kinds of waste, which affected the most important elements of life: air, water, and soil, and, therefore, human health. Pollution of the natural source of water with organic and inorganic pollutants is a global concern. The presence of chemicals in drinking water, rivers, seawater, or even in groundwater reservoirs over certain limits raises a major problem in maintaining the health of the population, especially in overcrowded and over-industrialized urban areas. Many organic pollutants in wastewater are responsible for a large number of negative effects on human health and environment: organic solvents, phenols, biphenyls, oils, greases, phthalates, bisphenol and its derivatives, dyes, hydrocarbons, surfactants, plasticizers, alcohols, esters, pharmaceutical wastes, pesticides, herbicides, fertilizers, and chlorinated compounds, etc.. There are countless studies on toxicity and health risks regarding the presence of chemicals in the environment, and therefore, for several decades, researchers have been searching for effective materials and methods for purifying wastewater and air. Different methods for the removal of organic pollutants from wastewaters are used: adsorption, filtration, ion exchange, coagulation, precipitation, ozonization, advance oxidation, reverse osmosis, just to mention a few. Among the possible techniques for wastewater treatments, the adsorption process by solid adsorbents shows potential as one of the most efficient methods for the treatment and removal of organic contaminants. Nowadays, a variety of specifically functionalized polymer adsorbents were prepared in the last decades for the removal of certain pollutants. These polymers are synthetic polymers based on styrene-divinylbenzene, methacrylates, glycidyl acrylates, metal-organic framework-based materials, porous organic polymers, etc. or natural polymers based on cellulose, cotton, cyclodextrin, chitosan, etc. Another class of adsorbents developed in recent years, the so-called green adsorbents, has been prepared from agricultural waste and by-products (vegetables, fruits). The natural bio-based materials are increasingly used as adsorbents for removing organic pollutants in water or volatile organic compounds (VOCs) in air due to certain advantages regarding their availability and low cost, high uptake capacity, and feasible regeneration.