Co-reporter:Dongbei Wu, Meirong Yi, Huiying Duan, Jingyan Xu, Qigang Wang
Carbon 2016 Volume 108() pp:394-403
Publication Date(Web):November 2016
DOI:10.1016/j.carbon.2016.07.025
We present a facile one-pot approach to fabricate tough TiO2-rGO-PDMAA nanocomposite hydrogel. Both synchronous polymerization of N, N-dimethylacrylamide (DMAA) monomer and reduction of graphene oxide (GO) sheets into porous hydrogel network are triggered by TiO2 nanoparticles under the UV irradiation. The reduction of GO is accompanied color changes of the hydrogel from light-brown to black. The interpenetrating double hydrogel network between PDMAA chains and rGO can be fabricated at a considerable GO content, at which the hydrogel exhibits tough mechanical strength, good swelling ratio and quick self-recovery character. Benefiting from the excellent carrier mobility and large surface area of the rGO, our hydrogel has an improved photo degradation performance for methylene blue, suggesting its potential application in the wastewater treatment.
Co-reporter:Dongbei Wu, Yawei Gao, Wenjun Li, Xiangning Zheng, YongGui Chen, and Qigang Wang
ACS Sustainable Chemistry & Engineering 2016 Volume 4(Issue 12) pp:
Publication Date(Web):September 15, 2016
DOI:10.1021/acssuschemeng.6b01691
Rare earth elements are an important strategic resource, and it is urgent that the rare earth industry continue to explore and develop novel separation methods and technologies. Herein, we fabricated an efficient semi-IPN alginate-clay-poly(n-isopropylacrylamide) (NIPAm) hydrogel by a frozen polymerization method with the help of UV light irradiation, where alginate was employed as the main adsorption functional compound. The as-prepared hydrogel exhibits tough, sponge-like hierarchical macroporous and reversible temperature-responsive characteristics. The maximum adsorption capacity of La3+ is 182 mg/g for the hydrogel composition of 5.0% NIPAm, 4.0% clay, and 3.0% alginate. The Langmuir isotherm fits the data very well, and the adsorption follows the pseudo-second-kinetic equation. The trace of La3+ ions can be effectively separated from the coexisting metal ions. After six repeated adsorption–desorption cycles, no obvious deformation of the shape and or loss of adsorption capacity of the bulk hydrogel is found, but the stress level of the original hydrogel is significantly enhanced. Our results indicate that the green, sustainable, adsorbent hydrogel may serve as a versatile platform for recovery, separation, and purification of rare earth ions and suggest its potential applications in the fields of hydrometallurgy industries and wastewater treatment.Keywords: Adsorption; Alginate; Clay; La (III); Poly(n-isopropylacrylamide) (PNIPAm);
Co-reporter:Song Bao, Dongbei Wu, Teng Su, Qing Wu and Qigang Wang
RSC Advances 2015 vol. 5(Issue 55) pp:44342-44345
Publication Date(Web):12 May 2015
DOI:10.1039/C5RA02162F
This communication describes the preparation of microgels via enzyme-triggered inverse emulsion polymerization, which provides an effective method for immobilizing enzymes with tunable catalytic performance and high stability.
Co-reporter:Xinhua Liu, Zubiao Wen, Dongbei Wu, Huanlei Wang, Jinhu Yang and Qigang Wang
Journal of Materials Chemistry A 2014 vol. 2(Issue 30) pp:11569-11573
Publication Date(Web):03 Jun 2014
DOI:10.1039/C4TA01944J
Herein, we describe a supramolecular approach to synthesize tough ionogels through self-initiated ultraviolet polymerization. The prepared ionogel can be used as the integrated electrolyte and separator in the all-solid supercapacitor. The electrochemical performance can be tuned by the temperature, and a higher value can be achieved at higher temperature.
Co-reporter:Xiangning Zheng, Dongbei Wu, Teng Su, Song Bao, Chuanan Liao, and Qigang Wang
ACS Applied Materials & Interfaces 2014 Volume 6(Issue 22) pp:19840
Publication Date(Web):October 27, 2014
DOI:10.1021/am505177c
Here, we provide an effective method to fabricate magnetic ZnO clay nanocomposite hydrogel via the photopolymerization. The inorganic components endow the hydrogel with high mechanical strength, while the organic copolymers exhibit good adsorption capacity and separation selectivity to La (III) ions. An optimized hydrogel has the maximum compressive stress of 316.60 ± 15.83 kPa, which still exhibits 138.98 ± 7.32 kPa compressive strength after swelling. The maximum adsorption capacity of La ion is 58.8 mg/g. The adsorption matches the pseudo-second-order kinetics model. La (III) ions can be effectively separated from the mixtures of La/Ni, La/Co, La/Cu, and La/Nd in a broad pH range (2.0 to 8.0). After six adsorption–desorption cycles, the hydrogel can maintain its adsorption capacity. This work not only provides a new approach to the synthesis of tough hydrogels under irradiation, but also opens up enormous opportunities to make full use of magnetic nanocomposite hydrogels in environmental fields.Keywords: clay; La (III) adsorption; magnetic separation; nanocomposite hydrogel; ZnO
Co-reporter:Baohui Zhu, Dongbei Wu, Yuhui Yang, Yonggui Chen, Wenjun Li, Junfang Guo, and Qigang Wang
Journal of Chemical & Engineering Data 2012 Volume 57(Issue 2) pp:553-560
Publication Date(Web):December 22, 2011
DOI:10.1021/je201122f
Super paramagnetic nanosorbents coated by saponified sec-octylphenoxy acetic acid (MSCA-12) were prepared as a kind of sorbent for magnetically assisted chemical separation of lanthanum(III) ions using a equilibrium batch experiment. The effects of various parameters such as contact time, pH, ion strength, interference ions, and metal ion concentration on the adsorption was investigated. The optimal pH for La(III) ions was equilibrium pH 7.0. The adsorption isotherm followed the Langmuir model with the maximum sorption capacity of 22.0 mg·g–1. The sorbent showed a good affinity toward La(III), and the stability of the sorbent in acidic solutions was also improved by the coating. The recovery of La(III) could be achieved using a 0.01 mol·kg–1 HCl solution. The repeated use three times of the adsorbent was possible. The sorbent was shown to have potential in the extraction of La(III) from the lake water, ground waters, and artificial wastewater.
Co-reporter:Dongbei Wu;Ling Zhang;Li Wang;Baohui Zhu ;Liyan Fan
Journal of Chemical Technology and Biotechnology 2011 Volume 86( Issue 3) pp:345-352
Publication Date(Web):
DOI:10.1002/jctb.2522
Abstract
BACKGROUND: The risk of environmental pollution is aggravated by the increasing application of considerable amounts of rare earth elements in advanced materials. This paper reports the preparation of novel magnetic alginate–chitosan gel beads and their application for adsorption of lanthanum ions from aqueous solution.
RESULTS: Stable magnetic alginate–chitosan gel beads with average diameter 0.85 ± 0.05 mm were prepared by loading iron oxide nanoparticles onto a combined alginate and chitosan absorbent. The performance of the prepared beads for the adsorption of lanthanum ions from aqueous solution was tested. It was found that various parameters, such as aqueous pH, contact time, metal ion concentration, ion strength and temperature, have an effect on the adsorption. Adsorption equilibrium was reached in 10 h and the maximum uptake capacity was 97.1 mg g−1. From the analysis of pH, FTIR and XPS data, it is proposed that lanthanum adsorption proceeds through mechanisms of cation exchange, electrostatic interaction and surface complexation, with the oxygen atoms the main binding sites. In addition, lanthanum ions could be selectively separated from coexisting base metal ions such as Pb (II), Cd (II), Co (II), Ni (II) and Cu (II) in the aqueous solution.
CONCLUSION: The prepared magnetic alginate–chitosan gel beads exhibit high uptake capacity and selectivity for lanthanum sorption, and thus can be used for adsorptive recovery of lanthanum from aqueous solutions. Copyright © 2010 Society of Chemical Industry
Co-reporter:Baohui Zhu, Nan Ma, Dongbei Wu, Yanhong Sun, and Wenjun Li
Industrial & Engineering Chemistry Research 2011 Volume 50(Issue 20) pp:11698-11705
Publication Date(Web):September 11, 2011
DOI:10.1021/ie200792j
Magnetic nanoparticles coated with mixtures of sodium oleate and saponified 2-ethylhexyl phosphonic acid mono-2-ethylhexyl ester were prepared as a kind of adsorbent for magnetically assisted chemical separation of copper ions. The extraction behavior was investigated using equilibrium batch experiment. The results demonstrated that mixtures of sodium oleate and saponified 2-ethylhexyl phosphonic acid mono-2-ethylhexyl ester had an evident synergistic effect on the copper extraction. The adsorption isotherm followed the Langmuir model, and the maximum sorption capacity of Cu(II) was 24.2 mg/g. The sorbent was highly selective toward Cu(II) at equilibrium pH 6.5, while the extraction of other metal ions was quite low in the binary solution systems. Artificial wastewater was prepared for selective removal of Cu(II) at the optimal experiment conditions. Desorption could be achieved using a 0.01 mol/L HCl eluent. The synergistic extraction mechanism of copper was confirmed to be ion exchange and surface complexation through pH analysis, Fourier transform infrared (FTIR), and X-ray photoelectron spectroscopy (XPS) techniques.
Co-reporter:Ling Zhang, Dongbei Wu, Baohui Zhu, Yuhui Yang, and Li Wang
Journal of Chemical & Engineering Data 2011 Volume 56(Issue 5) pp:2280-2289
Publication Date(Web):March 10, 2011
DOI:10.1021/je101270j
Magnetic alginate microcapsules containing the extractant 2-ethylhexyl phosphonic acid mono-2-ethylhexyl ester (P507) were prepared for adsorption and selective separation of neodymium using equilibrium batch experiments. The effect of various parameters such as adsorbent dose, contact time, temperature, pH, and metal ion concentration on adsorption was investigated. The results demonstrated that the adsorption data fit well the pseudosecond order kinetic model, and the Langmuir adsorption isotherm was suitable for the description of adsorption process. The adsorption capacity had the order Pb2+ > Nd3+ > Cu2+ > Zn2+ > Co2+ > Ni2+ for mono- and multicomponent systems, and Nd3+ could be selectively separated from the mixed Nd3+/Co2+ and Nd3+/Zn2+ solutions over the whole concentration range. Furthermore, solvent extraction and ion exchange mechanisms were confirmed to contribute to the adsorption process by FTIR spectra studies, pH analyses, and adsorption isotherms with possible structures of the complex proposed. Thermogravimetric analysis, desorption, and regeneration tests forecasted that the magnetic alginate P507 microcapsules would be an excellent candidate for their potential industrial application.
Co-reporter:Dongbei Wu, Chunming Zhu, Yonggui Chen, Baohui Zhu, Yuhui Yang, Qigang Wang, Weimin Ye
Applied Clay Science (July 2012) Volumes 62–63() pp:87-93
Publication Date(Web):July 2012
DOI:10.1016/j.clay.2012.04.015
Co-reporter:Xinhua Liu, Zubiao Wen, Dongbei Wu, Huanlei Wang, Jinhu Yang and Qigang Wang
Journal of Materials Chemistry A 2014 - vol. 2(Issue 30) pp:NaN11573-11573
Publication Date(Web):2014/06/03
DOI:10.1039/C4TA01944J
Herein, we describe a supramolecular approach to synthesize tough ionogels through self-initiated ultraviolet polymerization. The prepared ionogel can be used as the integrated electrolyte and separator in the all-solid supercapacitor. The electrochemical performance can be tuned by the temperature, and a higher value can be achieved at higher temperature.
