Removal of paraquat herbicide from water by textile coated with anionic cyclodextrin polymer

Abstract

The coating of anionic cyclodextrin polymer on polyethylene terephthalate (PET) textile was achieved by crosslinking between β-cyclodextrin (β-CD) and citric acid (CTR) to adsorb paraquat herbicide from aqueous solution. This coating performance (30 min, 170 °C) was 22.18% of weight gain which was corresponded to 0.51 mmol/g of ion exchange capacity (IEC). Then, the samples were characterized by scanning electron microscopy (SEM), attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR) and thermogravimetric analysis (TGA). The appropriated pH was 6.5 and the equilibrium time was 420 min. At 30 °C, the adsorption capacity towards paraquat (PQ) was enhanced (4.5, 18.9 and 23.7 mg/g) when the initial concentration of paraquat was increased (10, 50 and 250 mg/L). The adsorption kinetics was fitted to the pseudo-second-order model and the adsorption isotherm was suitable to Langmuir model. For the thermodynamic studies, the negative ∆G° revealed a spontaneous process, the negative ∆H° showed an exothermic process and the positive ∆S° displayed an enhanced disorder. Finally, the reusability of functionalized textile in methanol was reached 78.6% after six regeneration cycles and the stability of sample in various solvents was also studied. Graphical abstract Anionic cyclodextrin polymer coated on PET textile issued from the crosslinking between β-cyclodextrin and citric acid was used as an efficient adsorbent for paraquat removal from aqueous solution.

In vitro removal of paraquat and diquat from aqueous media using raw and calcined basil seed

“…Similar trends were reported previously (Kumari et al, 2019). Moreover, to obtain the information regarding the adsorption process relating to chemical reactions, mass transfer, and the adsorption order, pseudo-first-order and pseudo-second-order models were employed (Junthip et al, 2019).…”

“…Based on the fitting adsorption isotherm curves of these two models, with the use of BS1000, the correlation coefficient in the Langmuir isotherm model was ranged from 0.946-0.995 which was greater than that in the Freundlich isotherm model (0.826-0.984), except for paraquat in the commercial product. Therefore, monolayer adsorption for paraquat and diquat dominated on the homogeneous surface of BS and BS1000 (Junthip et al, 2019). Additionally, the q max value in BS1000 was greater than that in BS for each herbicide.…”

“…The use of pesticides in agricultural fields is very important as they are a useful means of reducing production efforts and increasing agricultural productivity (Junthip et al, 2019). Paraquat and diquat are widely used and classified as non-selective contact viologen herbicides that kill plant tissue on contact (Kumari et al, 2019).…”

Cyclodextrin Polymers and Cyclodextrin-Containing Polysaccharides for Water Remediation

“…Among the various methods employed to remove paraquat (a toxic herbicide commonly used for weed and grass control) from aqueous systems, adsorption has demonstrated higher efficiency, straightforward operation, and low cost. Junthip et al [161] have proposed and tested the adsorption of paraquat in aqueous solutions using a textile coated with anionic polycyclodextrin, with citric acid as an anchor agent. The removal performance was assessed considering different conditions, including an initial concentration of pesticide, pH of the solution, and adsorption temperature.…”

“…It was found that neutral pH and lower temperatures favored the adsorption of the pesticide on the functionalized textile. The reusability of the material was also relevant, reaching 78.6% of the maximum adsorption capacity after 6 regeneration cycles [161].…”