Single and binary adsorption of dyes from aqueous solutions using functionalized microcrystalline cellulose from cotton fiber

Hongjuan Bai,Junhang Chen,Xiangyu Zhou,Chengzhi Hu 한국화학공학회 2020 Korean Journal of Chemical Engineering Vol.37 No.11

Simultaneous removal of dyes in the effluents of printing and dyeing industries is challenging, and the mechanism of the co-adsorption of dyes is still unclear. In this context, a novel adsorbent based on microcrystalline cellulose from cotton fiber through a simplified chemical modification process was prepared. Methylene blue (MB) and neutral red (NR) were selected to investigate their adsorption/co-adsorption on such functionalized microcrystalline cellulose. The experimental adsorption results indicated that the adsorption quantity of both dyes was similar for the single solute. The kinetics of adsorption processes could be better described with the pseudo-second order models for both single and binary dye solutes. The results of the co-adsorption suggested that the extended Langmuir model could well predict equilibrium. The maximum adsorption capacity of MB and NR for the single systems was 115.2 and 83.2mg/g, respectively. Moreover, an antagonistic effect could be found in the binary dye solute. The obtained results revealed that the co-adsorption of dyes might be driven by hydrogen bonding, - stacking interaction as well as electrostatic interaction.

Biocolloid transport and deposition in porous media: A review

Hongjuan Bai,Junhang Chen,Yumu Hu,Gang Wang,Wenju Liu,Edvina Lamy 한국화학공학회 2022 Korean Journal of Chemical Engineering Vol.39 No.1

In an effort to protect surface and groundwater supplies from contamination, to assess the risk of microbial groundwater contamination and for the purpose of soil bioremediation, considerable efforts have been made to investigate biocolloid transport and retention in porous media. The current work provides an introductory overview of biocolloid transport and deposition in porous media so as to have a better understanding of the environmental behavior of biocolloids. In this review, biocolloid transport and deposition in porous media are discussed with an emphasis on transport and deposition mechanisms, numerical modeling and influencing factors. Moreover, major findings with respect to the forces acting on biocolloid transport and deposition are addressed, and research methods used to study biocolloid transport and deposition in porous media are also presented. Finally, based on the reported results, future research perspectives considering the microscopic pore scale study for biocolloid transport and deposition in porous media are also suggested.

Removal of fluoroquinolone antibiotics by adsorption of dopamine-modified biochar aerogel

Hongjuan Bai,Qiaofei Zhang,Xuan Zhou,Junhang Chen,Zihan Chen,Zhuangzhuang Liu,Jun Yan,Jing Wang 한국화학공학회 2023 Korean Journal of Chemical Engineering Vol.40 No.1

As emerging contaminants used for treating various tract infections, fluoroquinolones (such as enoxacin, ofloxacin, etc.) enter water bodies via point-source discharges of wastewater treatment plants and many of them raise environmental and health concerns. Herein, a novel adsorbent, derived from a useful renewable low-cost grapefruit peel, was prepared to investigate the adsorption behavior of fluoroquinolone antibiotics (enoxacin and ofloxacin). The obtained adsorbent was characterized by scanning electron microscopy (SEM), Fourier transform infrared (FTIR), X-ray diffraction (XRD) and thermo-gravimetric analysis and differential scanning calorimetry (TG-DSC). Further, the equilibrium sorption of the adsorption process was analyzed with isotherm models and kinetic models. Under optimal adsorption conditions, equilibrium data conformed to the Elovich model, and the kinetics of adsorption was fitted well with Redlich-Peterson model. Combined with thermodynamic analysis, electrostatic interaction, hydrogen bond, π-π stacking interaction were the possible adsorption mechanisms for both fluoroquinolone antibiotics onto the novel adsorbent. This work explored a promising adsorbent for the elimination of fluoroquinolone antibiotics in environmental remediation.

Characterization of modified sawdust, kinetic and equilibrium study about methylene blue adsorption in batch mode

Weihua Zou,Hongjuan Bai,Shuaipeng Gao,Ke Li 한국화학공학회 2013 Korean Journal of Chemical Engineering Vol.30 No.1

Methylene blue (MB) biosorption by citric acid modified pine sawdust (Pinus tabulaeformis) was studied from aqueous solutions. Batch experiments were conducted to determine the biosorption properties of the biomass. The Langmuir isotherm equation could fit the equilibrium data. The maximal equilibrium quantity of MB from Langmuir model was 111.46 mg g−1 at 293 K. The Elovich model adequately described the kinetic data in comparison to the pseudo-first-order model and pseudo-second-order model; the process involving rate-controlling step is very complex involving both boundary layer and intra-particle diffusion processes. The effective diffusion parameter Di and Df values were estimated at different initial concentration, and the average values were determined to be 5.76×10−8 and 2.12×10−7 cm2 s−1. Thermodynamic parameters showed that the adsorption of methylene blue onto pine sawdust biomass was feasible, spontaneous and endothermic under studied conditions. The physical and chemical properties of the biosorbent were determined by SEM, TG-DSC, XRD, and the point of zero charge (pHpzc) and the nature of biomass-dye interactions were evaluated by FTIR analysis, which showed the participation of COOH, OH and NH2 groups in the biosorption process. Biosorbents could be regenerated using 0.01 mol L−1 HCl solution at least three cycles, with up to 90% recovery. Thus, the biomass used in this work proved to be effective for the treatment of MB bearing aqueous solutions.

Renewable magnetic alginate-graphene oxide hybrid for efficient cationic dye removal

Wenju Liu,Hongjuan Bai,Weiqiang Gao,Zihan Chen,Zhuangzhuang Liu,Zilong Chen,Junhang Chen 한국화학공학회 2022 Korean Journal of Chemical Engineering Vol.39 No.10

A batch system was applied to investigate the behavior of adsorption of methylene blue (MB) and crystal violet (CV) from aqueous solution using a renewable magnetic alginate composite containing graphene oxide (M-GO/ Alg) in single and binary systems. The surface morphology and chemical structure of the adsorbent were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), thermogravimetric analysis (TGA), and vibrating sample magnetometer (VSM) analysis. The experimental data were fitted by the isotherm models and adsorption kinetics. And the maximum adsorption quantity of MB and CV reached 459.85 and 69.46mg/g at 298 K for M-GO/ Alg, respectively, as deduced from Langmuir model. After five successive adsorptive removal cycles for both dyes, no significant performance loss was observed for M-GO/Alg. Moreover, M-GO/Alg was easily separated under an external magnetic field. In binary system, MB and CV exhibited competitive adsorption. The obtained results suggested that M-GO/Alg can be used as an eco-friendly and recyclable adsorbent to remove cationic dyes from aqueous solutions.

Analysis of the effect of Rhodopseudomonas palustris on the lead exposure rat model using 1H-NMR-based metabolomics of urine and plasma

Chai Shutong,Zheng Ziyun,Liu Yani,Liang Yanhui,Yang Hong,Chen Jie,Bai Hongjuan,Yang Guan-e 대한독성 유전단백체 학회 2023 Molecular & cellular toxicology Vol.19 No.2

Background Rhodopseudomonas palustris had the eff ect of adsorbing and removing lead ions. Metabolomics is a comprehensive analysis based on several metabolites or biomarkers. Objective The paper aimed to investigate the restorative eff ect and the potential mechanisms of R. palustris in rats with the lead exposure model using 1 H-NMR metabolomics. Results Nine endogenous metabolites from rat plasma and 13 endogenous metabolites from rat urine were identifi ed as potential biomarkers of the symptoms of lead poisoning. The changes of metabolites levels in the plasma included lower levels of valine, acetoacetate, and N-acetyl-glycoprotein and a higher concentration of lactate, acetate, creatine, threonine, glutamine, and asparagine in model group compared with control group. Furthermore, increased citrate, succinate, dimethylamine, pyruvate, acetoacetate, α -oxoglutarate and asparagine, accompanied by decreased LDL/VLDL, taurine, creatinine, glucose and hippurate levels were observed in the model group compared with the control group in the urine. Biochemical parameters and histopathology examination dovetailed well with the metabolomics data. Treatment with R. palustris at a certain degree returned the levels of these metabolites to normal levels. Plasma and urine metabolomic analysis showed changes associated with energy metabolism, amino acids and fatty acid metabolism of lead exposure rats. Conclusion The eff ects of removing lead ions of R. palustris in rats with lead exposure were confi rmed. This research demonstrated that 1 H-NMR-based metabolomics was a promising tool to identify potential biomarkers and unravel protective eff ect mechanisms of R. palustris in lead poisoning rats.