IP: 141.135.81.238 On: Thu, 14 Jun 2018 17:54:39 Copyright: American Scientific Publishers Delivered by Ingenta Copyright © 2018 American Scientific Publishers All rights reserved Printed in the United States of America Article Journal of Nanoscience and Nanotechnology Vol. 18, 3218–3229, 2018 www.aspbs.com/jnn Surfactant Coated Silica Nanoparticles as Smart Scavengers for Adsorptive Removal of Naphthalene Savita Chaudhary 1 ∗ , Priyanka Sharma 2 , Arshpreet Kaur 1 , Rajeev Kumar 2 , and S. K. Mehta 1 1 Department of Chemistry and Centre of Advanced Studies in Chemistry, Panjab University, Chandigarh 160014, India 2 Department of Environment Studies, Panjab University, Chandigarh 160014, India This manuscript represents the synthesis of silica nanoparticles modified with four different types of cationic surfactants. The surfactant capped nanoparticles have better control over the size of silica nanoparticles. The as formed as model nanomaterials were used for the removal of naphthalene, a simple white crystalline polycyclic aromatic hydrocarbon (PAH) from aqueous media. The obtained materials were characterized by various microscopic and spectroscopic techniques. The average particle size of nanoparticles was approximately between 50 and 75 nm. The removal kinetic and adsorption studies were also conducted on silica nanoparticles with different contact time, initial concentrations of silica and naphthalene to achieve the optimum adsorption conditions. CPB func- tionalized nanoparticles have displayed higher removal efficiency of more than 85% as compared to 75 to 80% in case of CTAB, CTAC and CPC functionalized silica nanoparticles. The effects of various parameters like pH, adsorbent doses, naphthalene concentration and addition of salt have also been investigated for better understanding of the removal efficacy of prepared nanoparticles. Keywords: Pesticides, Naphthalene, Polycyclic Aromatic Hydrocarbon, Adsorption, Silica Nanoparticles. 1. INTRODUCTION Currently, the disproportionate use of polycyclic aromatic hydrocarbon (PAH) enhances the contamination risk of water resources, which causes a serious threat to the liv- ing organisms. Living beings are facing a lot of health connected troubles due to the extensive use of PAH. 1 2 There are various kinds of PAH molecules being used in the market, out of them naphthalene (white crystalline compound) is one of the most commonly used pesti- cide present in mothballs and other pest control products. Naphthalene has been registered for indoor and outdoor use to prevent moths and snakes from nesting. 3 Its expo- sure to humans could be through breathing, eating and drinking in the contaminated environment. Naphthalene is highly toxic, carcinogenic and mutagenic with well- documented ill effects like nausea, abdominal pain, anemia etc. in human beings. 4 5 Excessive exposure to naphtha- lene can damage the red blood cells leading to haemolytic anaemia. The excessive breathing of naphthalene fumes ∗ Author to whom correspondence should be addressed. can cause dizziness and later the gastrointestinal problems in humans. Accidental ingestion of naphthalene or naph- thalene affected moths can cause bloody urine and faeces. 6 The wearing of naphthalene protected clothes, diapers or using blankets may also cause skin irritation in human beings. 7 Earlier, various methods have been employed for remov- ing naphthalene from wastewater. 8–10 All these conven- tional water treatment methods are not much effective as naphthalene is non-biodegradable and insoluble in water. 1 In this prospective, various substrates such as zeolites, polymeric absorbents, water-ion exchange resins, meso- porous molecular sieves and activated carbons have been employed for the adsorptive removal of naphthalene. 7 Liu et al. 9 have solved the problem of lower solubility of naph- thalene by employing micellar media. Cooper et al. 11 have used the electron beam process for treating naphthalene waste present in aqueous media. Woo et al. 10 have stud- ied the photocatalytic degradation of some of the con- ventionally used PAHs such as naphthalene, phenanthrene, anthracene and degraded their removal by enhancing their 3218 J. Nanosci. Nanotechnol. 2018, Vol. 18, No. 5 1533-4880/2018/18/3218/012 doi:10.1166/jnn.2018.14650