Removal of 2,4-D herbicide from aqueous solution by aminosilane-grafted mesoporous carbons

Abstract

2,4-Dichlorophenoxyacetic acid (2,4-D) is the most commonly used herbicide in plant protection products. 2,4-D is poorly biodegradable and it is often found in aquatic environment. The development of an effective way to reduce the amount of this toxic contaminant from aqueous solution became an urgent issue. Therefore, in this study series of aminosilane-grafted mesoporous carbons were synthesized, characterized and then applied as adsorbents for 2,4-D. The impact of various factors such as the contact time (0-360 min) of herbicide with adsorbents, pH (2-11), temperature (25, 45, 60 °C) and initial concentration (6.25-150 mg/l) of the 2,4-D on the sorption capacity of materials was analyzed. The results proved that functionalization of mesoporous carbons with aminosilane increased the sorption capacity (q e = 142-191 mg/g) towards herbicide compared to pristine material (q e = 109 mg/g). The functional groups presented on the surface of materials enhanced the interaction between mesoporous carbons and herbicide. The most effective adsorbent for 2,4-D was the material that had the highest amount of basic groups on the surface (2.79 mmol/g) of all samples tested (0.06-0.52 mmol/g). For all studied materials the Langmuir model was the most suitable to describe the isotherms of 2,4-D adsorption (R 2 = 0.999). While the kinetics of herbicide adsorption on the functionalized mesoporous carbons were best fitted to the pseudo-second-order model. The presented study proved that the aminosilane-grafted mesoporous carbons could be promising adsorbents for effective removal of 2,4-D from aqueous environment.

Adsorption of 2,4-D and MCPA Herbicides on Carbon Black Modified with Hydrogen Peroxide and Aminopropyltriethoxysilane

“…The pH PZC concept seems to explain the adsorption behavior of 2,4-D and MCPA on APTES-modified carbon black well, suggesting that attractive and/or repulsive electrostatic interactions are one of the main mechanisms of phenoxyacetic herbicides adsorption on this adsorbent. These findings agree with the research results presented in other papers [ 10 , 11 , 12 , 13 , 14 , 15 , 16 ]. As in the paper [ 16 ], a significant reduction in adsorption on an adsorbent with an oxidized surface was observed here as well.…”

“…The results showed that 2,4-D adsorbed better and easier on the adsorbent with positively charged amine groups due to electrostatic interaction. A similar phenomenon (improved adsorption of phenoxyacetic herbicides) was also observed on other APTES-modified materials including mesoporous silica [ 12 , 13 ], mesoporous carbons [ 14 ], and a magnetic nanoadsorbent (Fe 3 O 4 @SiO 2 ) [ 15 ]. Our previously published work [ 16 ] investigated the adsorption of three phenoxy herbicides including MCPA, 2-(4-chloro-2-methylphenoxy) propanoic acid, and 4-(4-chloro-2-methylphenoxy) butanoic acid on the activated carbons with different surface chemical properties.…”

Sustainable synthesis of magnetic Sargassum siliquastrum activated carbon loaded with NiS nanorods for adsorption of 2,4-D herbicide

“…Conventional carbonaceous material adsorbents have difficulty removing 2,4-D because of their characteristics (Corwin and Summers 2012 ). The elimination of 2,4-D from water has thus been explored using a variety of modified AC, including chemically activated AC by H 3 PO 4 (Njoku and Hameed 2011 ), magnetic AC (AC/Fe 2 O 3 ) nanocomposite (Vinayagam et al 2022 ), AC fiber modified by nitric acid (Li et al 2018 ), AC-polyvinyl alcohol composite (Nawi et al 2018 ), and aminosilane-grafted mesoporous carbons (Goscianska and Olejnik 2019 ).…”

The Electrospray (ESI) and Flowing Atmosphere-Pressure Afterglow (FAPA) Mass Spectrometry Studies of Nitrophenols (Plant Growth Stimulants) Removed Using Strong Base-Functionalized Materials

“…The controlled release of bioactive compounds from hybrid materials or functionalized polymers is studied not only in the field of biomedicine [ 13 , 14 , 15 ] but also in agriculture [ 16 , 17 , 18 , 19 ]. In the case of nitrophenols, there are no sufficient studies on their controlled delivery using hybrid materials as transporting platforms.…”