Dataset Information

Synthesis of New Cyclodextrin-Based Adsorbents to Remove Direct Red 83:1.

ABSTRACT: Two cyclodextrins (CDs), γ- and hydroxypropyl (HP)-γ-CDs were used to synthesize new adsorbents by using epichlorohydrin (EPI) as cross-linking agent in order to remove Direct Red 83:1 (DR) from water. Both polymers were characterized in terms of Fourier spectroscopy, nuclear magnetic resonance, particle size distribution and thermogravimetric analysis. Experimental data for both polymers were well fitted to the pseudo-second order and intraparticle diffusion model, indicating that in the adsorption both chemical and physical interactions are essential in the removal of DR. Three different isotherm models were analyzed, concluding that γ-CDs-EPI followed the Temkin isotherm and HP-γ-CDs-EPI the Freundlich isotherm, these results suggested that the adsorption was happening onto heterogeneous surfaces. The results of the Gibbs free energy showed that the adsorption was spontaneous at room temperature. In order to eliminate the remaining dye after the polymer treatment, and advanced oxidation process (AOP) was considered, achieving more than 90% of removal combining both mechanisms.

SUBMITTER: Pellicer JA

PROVIDER: S-EPMC7576497 | biostudies-literature | 2020 Aug

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Synthesis of New Cyclodextrin-Based Adsorbents to Remove Direct Red 83:1.

Pellicer José A JA Rodríguez-López María Isabel MI Fortea María Isabel MI Gómez-López Vicente M VM Auñón David D Núñez-Delicado Estrella E Gabaldón José A JA

Polymers 20200820 9

Two cyclodextrins (CDs), γ- and hydroxypropyl (HP)-γ-CDs were used to synthesize new adsorbents by using epichlorohydrin (EPI) as cross-linking agent in order to remove Direct Red 83:1 (DR) from water. Both polymers were characterized in terms of Fourier spectroscopy, nuclear magnetic resonance, particle size distribution and thermogravimetric analysis. Experimental data for both polymers were well fitted to the pseudo-second order and intraparticle diffusion model, indicating that in the adsorp ...[more]

PMID: 32825485

Similar Datasets

Project description:Nitrites are metastable anions that are derived from the oxidation of ammonia by agricultural pollution, sewage, decaying protein, and other nitrogen sources. They are a recognized environmental issue due to their role in eutrophication, as well as in surface and groundwater contamination, being toxic to almost all living creatures. Recently, we reported on the high efficiency of two cationic resins (R1 and R2) forming hydrogels (R1HG and R2HG) by dispersion in water in removing anionic dyes from water by electrostatic binding. Here, aiming at developing adsorbent materials for nitrite remediation, R1, R2, R1HG, and R2HG were first tested in adsorption experiments in batches monitored by UV-Vis methods, using the Griess reagent system (GRS) in order to assess their removal efficiency by contact over time. Particularly, samples of water appositely contaminated with nitrites were analyzed by UV-Vis before and during treatment with the hydrogels. The initial concentration of nitrites was quantified (118 mg/L). Then, the removal of nitrites over time, the removal efficiency of R1HG (89.2%) and of R2HG (89.6%), their maximum adsorption (21.0 mg/g and 23.5 mg/g), as well as the adsorption kinetics and mechanisms were evaluated. Additionally, R1HG- and R2HG-based columns (h = 8-10 cm, ØE = 2 cm) mimicking mini-scale decontamination systems by filtration were used to rapidly filter samples of water polluted with nitrite that were under pressure. R1HG and R2GH were capable of totally removing nitrites (99.5% and 100%) from volumes of nitrite solutions that were 118 mg/L that is 10 times the volumes of resins used. Additionally, when extending filtration to increasing volumes of the same nitrite solution up to 60 times the volume of resins used, the removal efficiently of R1HG decreased, and that of R2HG remained stable at over 89%. Interestingly, both the worn-out hydrogels were regenerable by 1% HCl washing, without a significant reduction in their original efficiency. There is a lack of studies in the literature reporting on novel methods to remove nitrite from water. R1HG and especially R2HG represent low-cost, up-scalable, and regenerable column-packing materials with promise for applications in the treatment of drinking water contaminated by nitrites.

Project description:Water pollution from dyes is harmful to the environment, plants, animals, and humans and is one of the most widespread problems afflicting people throughout the world. Adsorption is a widely used method to remove contaminants derived from the textile industry, food colorants, printing, and cosmetic manufacturing from water. Here, aiming to develop new low-cost and up-scalable adsorbent materials for anionic dye remediation and water decontamination by electrostatic interactions, two cationic resins (R1 and R2) were prepared. In particular, they were obtained by copolymerizing 4-ammonium methyl and ethyl styrene monomers (M1 and M2) with dimethylacrylamide (DMAA), using N-(2-acryloylamino-ethyl)-acrylamide (AAEA) as cross-linker. Once characterized by several analytical techniques, upon their dispersion in an excess of water, R1 and R2 provided the R1- and R2-based hydrogels (namely R1HG and R2HG) with equilibrium degrees of swelling (EDS) of 900% and 1000% and equilibrium water contents (EWC) of 90 and 91%, respectively. By applying Cross' rheology equation to the data of R1HG and R2HG's viscosity vs. shear rate, it was established that both hydrogels are shear thinning fluids with pseudoplastic/Bingham plastic behavior depending on share rate. The equivalents of -NH3+ groups, essential for the electrostatic-based absorbent activity, were estimated by the method of Gaur and Gupta on R1 and R2 and by potentiometric titrations on R1HG and R2HG. In absorption experiments in bulk, R1HG and R2HG showed high removal efficiency (97-100%) towards methyl orange (MO) azo dye, fluorescein (F), and their mixture (MOF). Using F or MO solutions (pH = 7.5, room temperature), the maximum absorption was 47.8 mg/g in 90' (F) and 47.7 mg/g in 120' (MO) for R1, while that of R2 was 49.0 mg/g in 20' (F) and 48.5 mg/g in 30' (MO). Additionally, R1HG and R2HG-based columns, mimicking decontamination systems by filtration, were capable of removing MO, F, and MOF from water with a 100% removal efficiency, in different conditions of use. R1HG and R2HG represent low-cost and up-scalable column packing materials that are promising for application in industrial wastewater treatment.

Dataset Information

Synthesis of New Cyclodextrin-Based Adsorbents to Remove Direct Red 83:1.

Publications

Synthesis of New Cyclodextrin-Based Adsorbents to Remove Direct Red 83:1.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets