Pesticides in aquatic environments and their removal by adsorption methods.

High-performance removal of diazinon pesticide from water using multi-walled carbon nanotubes

The quality of water is continuously under threat as increasing concentrations of pollutants escape into the aquatic environment. However, these issues can be alleviated by adsorbing pollutants onto adsorbents. Chitosan and its composites are attracting considerable interest as environmentally acceptable adsorbents and have the potential to remove many of these contaminants. In this review the development of chitosan-based adsorbents is described and discussed. Following a short introduction to the extraction of chitin from seafood wastes, followed by its conversion to chitosan, the properties of chitosan are described. Then, the emerging chitosan/carbon-based materials, including magnetic chitosan and chitosan combined with graphene oxide, carbon nanotubes, biochar, and activated carbon and also chitosan-silica composites are introduced. The applications of these materials in the removal of various heavy metal ions, including Cr(VI), Pb(II), Cd(II), Cu(II), and different cationic and anionic dyes, phenol and other organic molecules, such as antibiotics, are reviewed, compared and discussed. Adsorption isotherms and adsorption kinetics are then highlighted and followed by details on the mechanisms of adsorption and the role of the chitosan and the carbon or silica supports. Based on the reviewed papers, it is clear, that while some challenges remain, chitosan-based materials are emerging as promising adsorbents.

https://www.mdpi.com/1420-3049/26/3/594/pdf

Recent Developments in Chitosan-Based Adsorbents for the Removal of Pollutants from Aqueous Environments

Pesticides are a mixture of substances and widely used for destroying, combating, or controlling pests Various technologies used to control pesticide concentration in nature include photolysis, photo-Fenton, semiconductor-based photocatalysis and photoelectrocatalysis, etc. Among them semiconductor based photocatalysis has attracted huge attention due to its more feasible and higher rate of degradation which further leads to a great charge of mineralization. This review mainly focuses to discuss and summarize numerous characteristics of photocatalytic elimination of pesticides. The discussion includes the mechanism of semiconductor photocatalytic degradation, modifications over semiconductors that are available in the literature to increase the efficiency of the degradation process, and finally optimization of different parameters of a process for enhancement in the degradation course. The parameters elaborated in this study are pH of the system, amount of semiconductor catalyst, initial concentration of pesticides, calcination temperature of catalyst, and wavelength as well as the intensity of light.

Semiconductor based photocatalytic degradation of pesticides: An overview

Extreme utilization of pesticides for agricultural purposes increases the level of pesticide content in water. Seasonal use of pesticides can cause increased concentrations at potable water abstraction sites as a shock load, which can be difficult for conventional treatment processes to deal with. Choosing the right water treatment method to remove pesticides hangs on the nature of pesticides and the effectiveness of the technique. The focus of this review is to discuss the current developments and progress in the use of various techniques for possible removal of pesticides from wastewater. Some of these processes include advanced oxidation, adsorption, activated sludge treatment, bioreactors and membrane technologies. The solo and mixed treatment techniques have been reviewed in detail and analyzed rigorously. The utilization of hybrid disposal technologies exhibit potential for the development of innovative pesticide removal techniques. Form the process effectiveness point of view, it is very important to thoroughly analyze the composition of the influent and identify the best removal technique. Furthermore, study emphasizes on designing of water treatment plant, the decentralization of water treatment and economical approaches for removal of various types of pesticides from wastewater are discussed.

Recent trends and future challenges of pesticide removal techniques – A comprehensive review

In recent years, water pollution and pesticide residues in the food chain have become a serious environmental and health hazard problem. Therefore, an efficient technology is essential for complete mineralization of pesticides to non-toxic forms. Nanotechnology offers many potential benefits to improve existing environmental technologies using new materials with effective performance, resulting in less consumption of energy and materials. The aim of this review is to compile and study current publications regarding pesticides removal by nanotechnology. This study discusses the applications, advantages and limitations various nanotechnology processes for removal of pesticides.

http://www.ijnnonline.net/article_30199_d07958a9d6abde6ff5221c123ae3f28e.pdf

T. Taghizade Firozjaee

Papers

Application of Nanotechnology in Pesticides Removal from Aqueous Solutions - A review

The removal of diazinon from aqueous solution by chitosan/carbon nanotube adsorbent