Cellulose nanocrystal modified with 3‐chloro propyl trimethoxysilane: a new bio‐adsorbent for nitrate removal from water

Abstract

In this work, preparation, characterization and nitrate removal ability of a chemically modified cellulose nanocrystal (CPTMS/CNC) were investigated for the first time. The FTIR, FESEM, EDX and TG analyses confirmed the successful modification of the cellulose nanocrystal (CNC) by 3-chloro propyl trimethoxysilane (CPTMS) and the thermal stability of CPTMS/CNC. The optimum removal efficiency (86.5%) occurred at initial pH of 7 and room temperature (~25°C) with an initial nitrate concentration of 20 mg/L, contact time of 10 min and CPTMS/CNC dosage of 3 g/L. The nitrate adsorption dropped noticeably in the presence of sulphate, followed by bicarbonate, chloride and phosphate, respectively. The kinetic adsorption data were fitted well with the pseudo-second-order kinetic model and the adsorption process involved two stages. The equilibrium adsorption data obeyed the Freundlich isotherm model. Thermodynamic analysis suggested a spontaneous and exothermic adsorption process with a decrease in random collisions at the solid-solution interface.

A comprehensive review on nitrate and phosphate removal and recovery from aqueous solutions by adsorption

“…Nitrate adsorbents, such as chitosan hydrogel beads (Chatterjee & Woo 2009), chitosan/PEG, and chitosan/PVA polymer composites (Rajeswari et al 2016) were synthesized through grafting and chelating with chitosan. Chemically modified cellulose nanocrystal (CNC) was investigated for nitrate removal from aqueous solution by Manhooei et al (2019). According to their experiment, an optimum nitrate removal efficiency of 86.5% was achieved at pH 7, initial nitrate concentration of 20 mg/L, room temperature, and the dose of 3 g/L within 10 minutes, and nitrate adsorption was found to be affected by anions in the order of SO 4 2À .…”

“…Cl À . PO 4 3À (Manhooei et al 2019). Yang et al (2017) also synthesized modified steel slag (MSS) by mixing steel slag, aluminum hydroxide, and deionized water using a ratio of 3:0.45:2 followed by aging and thermal activation at 800°C.…”

“…Most of the reported nitrate adsorbents had negative value standard free energy (ΔG o ) which indicates spontaneous adsorption (Xiao et al 2017). The value of ΔG o was observed to increase (Banu et al 2019;Manhooei et al 2019;Alagha et al 2020), and decrease (Chatterjee & Woo 2009;Rezaei Kalantary et al 2016;Song et al 2016;Manhooei et al 2019) with a temperature that indicates the adsorption process is favorable at low and high temperature, respectively. Endothermic (Rajeswari et al 2016;Rezaei Kalantary et al 2016;Song et al 2016), and exothermic nature of the adsorption process (Chatterjee & Woo 2009;Deng & Shi 2015) was observed by a positive and negative value of enthalpy (ΔH o ), respectively.…”

Novel cellulose supported 1,2-bis(4-aminophenylthio)ethane Ni(ii) complex (NiII(BAPTE)(NO3)2-Cell) as an efficient nanocatalyst for the synthesis of spirooxindole derivatives

“…[40][41][42][43][44][45] At the nanoscale, cellulose nanocrystals, in addition to their cellulose properties, also exhibit specic properties of nanomaterials, such as dispersion and greater contact surface area. 46 Cellulose with a modied surface has many applications. [47][48][49] For example, by placing a coating of aluminum oxide on the surface of cellulose, a suitable compound is obtained to adsorb metal halides from ethanol.…”

Nanocrystalline cellulose based on chitosan hydrogel structure as a biological adsorbent for effluent of fish culture farms

“…Extensive development of aquaculture increases the discharge of farm e uents into natural ecosystems such as surface waters and rivers, which contain large amounts of nitrogen and phosphate compounds, and its discharge into the aquatic environment causes degradation and adverse effects (Nora'aini et al, 2005). In aquatic ecosystems, the most common ionic forms of mineral nitrogen are ammonium (NH4), nitrate (NO3) and nitrite (NO2).…”