الفهرس 
Introduction and Review of LiteratureOnly 14 pages are availabe for public view
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Abstract
Water pollution is a major challenge for environmental scientists and a growing interest in largescale pollution of surface and groundwater with organic and inorganic compounds due to the rapid development of the chemical and petroleum industries over the past several decades. Therefore, removing water pollutants such as heavy metals, dyes, and pesticides has become so important. Several studies have been conducted to suggest innovative and effective materials to treat water from pollutants. Contamination of water resources with toxic heavy metals from industrial wastewater is a serious global problem related to the environment and human health. Long-term exposure may lead to Alzheimer’s disease, Parkinson’s disease, muscle atrophy, multiple sclerosis, cramping, nausea, vomiting, difficulty breathing, emotional instability and insomnia. The toxic effects of dyes are a major concern about their use. The textile industry consumes the largest share of dyes. Approximately 10% of the dyes used in the manufacturing industries are released into the environment, which poses a strong threat to the environment. It is estimated that more than 10,000 types of dyes used in the industry are directly disposed of. The majority of dyes are considered carcinogens, causal to gene mutations and chromosomal abnormalities, breathing disorders and skin diseases. Dye molecules in polluted water prevent sunlight from reaching the water system leading to a deterioration in the level of dissolved oxygen leading to toxic effects on living organisms. The increasing use of pesticides to obtain higher agricultural yields causes many environmental and health problems. The excessive use of these agrochemicals in fields and orchards pollutes surface and groundwater. Exposure to pesticides is linked to various diseases, including cancer, hormonal disorders, asthma and allergies. This situation of environmental and health impacts needs urgent attention with an acceptable solution to remove heavy metals, dyes and pesticides from industrial wastewater, agricultural drainage. Various treatment techniques and materials like adsorption, biological treatment, oxidation, ion-exchange, filtration, precipitation, electrolysis, reverse osmosis, coagulation, biofloulents, and biodegradable materials have been employed to remove heavy metals, dyes and pesticides from wastewater. Among the techniques stated above, adsorption is arguably the most sought after techniques for removing heavy metals, dyes and pesticides from industrial effluents and wastewater owing to its excellent efficiency, process simplicity as well as cost effectiveness. In the present study, successfully synthesized novel nanocomposite materials like oxidized activated carbon (OAC), cetyltrimethyl ammonium bromide intercalated and branched poly(hydroxystyrene) functionalized montmorillonite nano-composite (BPS-CTABMMT) and polymer clay nanocomposite (PHS-MMT). Structural elucidation of these synthesized nanocomposite materials was carried out by Fourier-transform infrared spectroscopy (FT-IR) spectroscopic technique, surface morphology of nanocomposite materials was carried out by using scanning electron microscopy (SEM). Surface area of the adsorbent particles was measured by Brunauer-Emmett-Teller (BET) surface area analyzer. Thermal behavior of assynthesized materials was studied by thermal gravimetric analyses (TGA) and diffraction pattern analysis was carried out by X-ray powder diffraction analysis (XRD). Size and shape of the assynthesized materials was investigated using Transmission electron microscopy (TEM). Batch adsorption experiments using the modified materials were carried out to investigate the heavy metal Co(II), cationic dyes, methylene Blue (MB), rhodamine-B (RB), Crystal Violet (CV) and Carbaryl pesticide removal capacity from contaminated water. Various experimental parameters including adsorbent dosage, initial concentration of pollutant, contact time between adsorbent and pollutant, and pH of the system were optimized for obtaining best adsorption. Further, the kinetics and equilibrium studies were investigated via Lagergren pseudo-first-order, and McKay’s pseudo-second-order kinetics, while the adsorption isotherm was investigated via the linear transformation of Langmuir, Freundlich and Sips isotherms models. These results clearly indicated the effective adsorption of heavy metals, dyes and pesticide in aqueous medium and waste water by using the novel developed adsorbents, (OAC), (BPS-CTAB-MMT) and (PHSMMT), a promising adsorbents could be successfully applied for removing of organic and inorganic pollutants from water. The results showed that the highest adsorption capacity of cobalt Co (II) using OAC adsorbent was 83.6 mg /g and followed the pseudo-second-order model and fitted with the equilibrium data of Frindlish model. The pH 4 was appropriate for the optimum adsorption process. While the highest adsorption capacity of the second adsorbent BPS-CTAB-MMT for MB, RB and CV were 84.8, 125.3 and 120.8 mg/g, respectively. It follows the pseudo-second-order model and the Sips isotherm model. The suitable pH of the adsorption for MB, RB and CV, were 2.11, 5 and 5.75 respectively. The highest adsorption capacity of BPS-MMT for Carbaryl insecticide was 48.9 mg/g. It followed the pseudo-secondorder model and the Langmuir isotherm model. The appropriate pH was 4. The results of this study indicated that these novel prepared adsorbents applied are promising adsorbents for removing organic and inorganic pollutants from aqueous solutions.