CHINESE JOURNAL OF CHEMICAL ENGINEERING
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2025
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IF 3.7
Huagui Jin,Xuebin An,Shizhao Wang,Yunshan Wang,Gang Yang,Yong Sun
s This study investigates the removal of fluorine (F) impurities from phosphogypsum (PG) using steam as the reaction medium. The effects of the reaction atmosphere, temperature, time, and steam velocity on F impurities removal were systematically examined. The results showed that with a steam velocity of 0.0184 m·s −1 , a reaction temperature of 700 °C, and a reaction time of 60 min, the F removal rate reached 95.87%. Further investigations into the defluorination mechanism revealed that steam and SiO 2 synergistically enhance fluoride removal, playing a crucial role in improving the defluorination efficiency. Kinetic analysis of the defluorination process, based on the shrinking core model (SCM), indicated that internal diffusion is the rate-controlling step, with the activation energy of 30.12 kJ·mol −1 . This study identifies optimal conditions for PG defluorination and proposes a defluorination mechanism, contributing to the theoretical understanding of impurity removal through the thermal treatment of PG.
研究领域:
化学工程
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环境科学
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DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2025
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IF 8.5
Liping Mei,Jiao Wei,Ruirui Yang,Wei Guo,Yuexin Liu,Fei Ke,Chuanyi Peng,Ruyan Hou,Guijie Chen,Junsheng Liu,Daxiang Li,Xiaochun Wan,Huimei Cai
To mitigate the risk associated with water-soluble fluoride in tea and to have less influence on the contents of tea infusion, a highly selective lanthanum modified silk fibroin (SF) and polyvinyl alcohol (PVA) composite film (SF/PVA-La) was prepared to remove fluoride from brick tea infusion. Notably, SF/PVA-La could remove about 48 % of the fluoride from in brick tea infusion within 30 min. Importantly, the reduction in total tea polyphenols in brick tea did not exceed 10 %, and the reduction in caffeine was only 0.4 %. In addition, the Langmuir model revealed a maximum fluoride adsorption capacity of 9.15 mg/g for SF/PVA-La in brick tea infusion. Both FTIR and XPS analyses confirmed that SF/PVA-La engages in electrostatic adsorption of fluoride ions, with ion exchange occurring between the hydroxyl groups on its surface and the fluoride ions. These findings underscore the potential of SF/PVA-La as an effective material for selective fluoride removal from brick tea infusions.
研究领域:
材料科学
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环境科学
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DOI
PubMed
高影响因子
ADVANCED FUNCTIONAL MATERIALS
·
2023
·Vol. 33
·期 20
·2213999
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IF 19
Yizhong Zhang,Liuchang Wang,Ruichi Zhang,Chao He,Lixia Jia,Xunliang Wang,Xuemin Feng,Tianxiang Jiang,Baolong Xie,Xiaolei Ma,Junrui Cao,Yuhui Ma,Xin Tan,Tao Yu
Because of spontaneous agglomeration effect and undesirable electronic state of Zr sites on the surface, zirconium (hydro)oxides generally exhibit suboptimal defluoridation capacity. Herein, a template confinement-ligand anchoring strategy is developed by utilizing confined growth of zirconium hydroxide (ZH) inside chitosan hydrogel beads (CHB) and subsequent anchoring of fumaric acid (fm) on its surface Zr sites in a monodentate mononuclear coordination mode. This technique leads to uniform dispersion of ultrafine fmZH (≈3.4 nm) and tunable electron density at the Zr sites. Due to the electron-withdrawing ability of fm, electron-delocalized Zr sites increase the orbital energy level matching and vacate Zr 4d orbitals to promote hybridization with the F 2p orbitals. Ultimately, robust Zr F bond can be formed as a result of reduced the adsorption energy toward fluoride ions. The defluoridation capacity shows positive linear relationship with the electron extraction ability of ligands. The saturation adsorption capacity and dynamic treatment capacity of CHB@fmZH are 10.8 and 45.9 times higher than that of CHB@ZH, respectively, owing to high electron extraction (0.098 e − ) of fm. This study offers a novel insight into the design and synthesis of high-efficiency metal oxide adsorbents by steering its surface metal sites’ electronic state through ligand effect.
研究领域:
材料科学
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环境科学
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DOI
高影响因子
CARBOHYDRATE POLYMERS
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2025
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IF 12.5
Wenyue Yu,Huan Guo,Ya Liu,Yangyu Zhou,Yue Xiao,Jinrong Bai,Yanping Wu,Kai Zhong,Yina Huang,Hong Gao
High fluoride intake from tea consumption poses significant health risks, necessitating the development of defluorination adsorbents in the food industry. Defluorination from tea is particularly challenging due to the requirements for high adsorption efficiency, preservation of sensory quality, and high recovery rates of the adsorbents. In this study, we introduced an innovative aerogel bead, CMC-Al/HAP, which integrates hydroxyapatite (HAP) into a carboxymethylcellulose (CMC) sphere crosslinked with aluminum chloride through a green and straightforward process. Our results demonstrated that CMC-Al/HAP achieved a remarkable fluoride adsorption capacity of 23.51 ± 0.46 mg/g. Subsequently, we investigated the impact of various adsorption parameters, kinetics, isotherms, coexisting anions, and recycling potential on the adsorption behavior of the beads. The adsorption kinetics followed the pseudo-second-order and dubinin-radushkevich models, while the Langmuir isotherm provided a good fit for the adsorption data. Characterization studies conducted before and after adsorption indicated that the adsorption mechanism mainly involved ion exchange and electrostatic interactions. Notably, CMC-Al/HAP effectively reduced fluoride levels in brick tea infusions without affecting quality such as tea color, catechins, and aroma. These findings underscore the potential of CMC-Al/HAP aerogel beads as a practical defluorination solution, providing valuable insights into alternative methods for defluorination in the tea industry.
研究领域:
食品科学
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环境科学
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DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2014
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IF 4.058
Nantong Zhang,Xuan Yang,Xinyao Yu,Yong Jia,Jin Wang,Lingtao Kong,Zhen Jin,Bai Sun,Tao Luo,Jinhuai Liu
In this study, adsorption potential of a typical aluminum-based metal–organic frameworks (MOFs), Al 12 O(OH) 18 (H 2 O) 3 (Al 2 (OH) 4 )(BTC) 6 ·24H 2 O (referred as MIL-96), was investigated for defluoridation of drinking water using batch experiment. The effects of different parameters such as pH, contact time, initial fluoride concentration, and competing anions were studied to understand the adsorption behavior of the adsorbent under various conditions. Optimum removal of fluoride ions occurred in a pH range of 3–10. The results indicated that the defluoridation efficiency and aluminum residual of MIL-96 were far superior to that of activated alumina (AA) or nano-alumina (NA). The Langmuir equilibrium model was found to be suitable for describing the fluoride sorption on MIL-96. The maximum fluoride uptake capacity for MIL-96 was calculated to be 31.69 mg g −1 at the temperature of 298 K. Moreover, there were no significant influence on fluoride removal by MIL-96 in the presence of chloride, nitrate, sulfate, bicarbonate and phosphate. Temperature study was carried out at 298 K, 308 K and 318 K revealed that the adsorption process was endothermic reactions. In column tests using real groundwater as influent, about 140 bed volumes (BVs) of groundwater were treated before breakthrough was reached under space velocities (SVs) of 4 h −1 . Results from this study demonstrated the MIL-96 is a promising adsorbent that can be potentially used into drinking water processes.
研究领域:
环境科学
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材料科学
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DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2020
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IF 5.774
Qi Dong,Dongxu Yang,Liang Luo,Qiang He,Fangheng Cai,Si Cheng,Yi Chen
Chronic accumulation of fluoride (F − ) threats human health and eventually brings about skeletal fluorosis, dental fluorosis and joint deformation, which has aroused global attention. As an emerging technique, electrosorption presented great potential in wastewater purification. The key role in electrosorption is the exploitation of economical, environmentally-friendly and efficient electrode material. Nowadays, many existing investigations on the preparation of porous carbon material focused on the introduction of extra dopant and activation reagent. However, the information concerning the preparation of pure porous biochar and the inherent environmental significance is neglected. Here, a win–win strategy, named conversion waste biomass into porous biochar, has been applied in capacitive fluorine removal. The results indicated that the capacity of porous biochar electrode was 1.28 mg/g, which was improved by 48.8% in contrast to activated carbon electrode. Furthermore, competition experiments revealed concentration-dependence interference in the present of foreign ions. Electrosorption cycle experiment manifested excellent stability of the biochar electrodes. The electrode was regenerated without consuming any chemicals and could produce current for energy recovery. More importantly, continuous-flow experiment showed that the removal efficiency of F − was 91.98% at the synthetic wastewater. High specific capacitance, low internal resistance and appropriate pore distribution were responsible for the F − removal mechanism. Overall, this work would pioneer a facile method in the preparation of low-price electrode material and their potential applications in environmental remediation.
研究领域:
环境工程
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材料科学
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水处理
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DOI
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
·
2013
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IF 3.365
Xudong Zhao,Dahuan Liu,Hongliang Huang,Wenjuan Zhang,Qingyuan Yang,Chongli Zhong
The stability of metal–organic frameworks (MOFs) in fluoride solutions was studied based on 11 water-stable MOFs (MIL-53(Fe, Cr, Al), MIL-68(Al), CAU-1, CAU-6, UiO-66(Zr, Hf) and ZIFs-7, -8, -9), and several factors were found to have large influence, such as the central metal activity, pore topology and coordination number. Furthermore, the defluoridation performance of UiO-66(Zr) was investigated comprehensively, which shows an adsorption capacity of 41.36 mg g −1 that is higher than most of the reported adsorbents. The initial pH of fluoride solution has little effect in neutral range, while shows a negative effect when pH >9.0; the adsorption data of UiO-66(Zr) fit well with the Langmuir model, and pseudo-second-order kinetic model was found to be suitable for depicting the F − adsorption process, and finally, it was observed that the extent of the effect of co-existing ions is largely ion-dependent. On the basis of the systemic study, this work suggests that increasing the number of –OH groups is an efficient strategy to improve the defluoridation performance of MOFs, and MOFs are promising adsorbents for defluoridation in waste water.
研究领域:
材料科学
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环境科学
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DOI
高影响因子
DESALINATION
·
2023
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IF 9.9
Wei Wang,Pin Ma,Haibo Li
Transition metal oxides (TMOs) have great application potential in capacitive deionization (CDI), which can selectively extract ions from water with high charge efficiency and low contamination. Previous studies have found that cationic segregation of TMOs has adverse effects on their electrochemical performance, but its effect on CDI remains unclear. Herein, we demonstrate for the first time that Ca 2+ segregation provides more sites for F − adsorption by synthesizing Ca 2 Mn 3 O 8 for CDI selective defluorination . The Ca 2 Mn 3 O 8 material has a graded porous structure , low charge transfer resistance , high specific capacitance (255.64 F/g, 1 mV/s, 0.5 M NaF solution) and good charge/discharge reversibility (about 100 % charge specific capacity retention after 50 cycles). Moreover, Ca 2 Mn 3 O 8 has a high specific adsorption capacity (SAC) for NaF (1419.07 μmol/g) and excellent cyclic stability (capacity retention rate is 96.69 % after 100 cycles). The Ca 2+ segregation from lattice to surface provides more sites for F − adsorption and greatly shortens ion transport paths. Density functional theory (DFT) calculation further suggests that the adsorption energy of Ca 2 Mn 3 O 8 for F − is much greater than that of Cl − . As a result, the removal rate of F − by Ca 2 Mn 3 O 8 in mixed solutions is up to 20 times higher than that of Cl − .
研究领域:
材料科学
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环境工程
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DOI
高影响因子
ENVIRONMENTAL GEOCHEMISTRY AND HEALTH
·
2024
·Vol. 47
·期 1
·1-18
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IF 3.2
Gong Huichun,Ke Pingchao,Zhou Yipeng,Xu Lingling,He Guang,Jian Peng
Fluoride contamination is a serious environmental problem in lepidolite hydrometallurgy wastewater. The treatment of fluoride-bearing wastewater is challenging because of the presence of coexisting ions including lithium (Li + ), rubidium (Rb + ), silicate (SiO 3 2− ), sulfate radical (SO 4 2− ). However, aluminum-modified zeolite (Al@zeolite) with sufficient hydroxyl groups and high adaptability has unique advantages for eliminating fluoride from lepidolite hydrometallurgy wastewater. Al@zeolite was prepared on natural zeolite by an atmospheric process and then used for the adsorption of fluorine from fluoride-bearing wastewater produced by the lepidolite hydrometallurgy process. The results of material characterization confirmed the successful immobilization of aluminum within the zeolite pores and indicated the formation of zeolite-Al–OH. The zeolite host significantly enhanced the chemical stability of Al@zeolite against pH changes for a wide pH range of 2.0–10.0. The adsorbent had a surface area of 33.46 m 2 /g and demonstrated excellent capacity and selectivity for fluoride adsorption. Notably, a maximum adsorption of 98.6% was observed at a pH value of 6.0 for a duration of 20 min with a fluoride content of 20 mg/L, and the equilibrium concentration decreased to 0.4 mg/L. The results of fluorine adsorption showed that fluoride uptake onto Al@zeolite agreed well with the pseudo-second-order kinetic model and the Langmuir isotherm model. The reusability of the substance was evaluated for up to eight cycles following consecutive regeneration with 0.2 mol/L AlCl 3 . The exhausted Al@zeolite was effectively regenerated through simple alkaline treatment for recycling. The above results verified that Al@zeolite is a new kind of efficient defluoridation adsorbent for lepidolite hydrometallurgy wastewater with practical application prospects.
研究领域:
环境科学
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材料科学
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DOI
PubMed
高影响因子
Advanced Science
·
2024
·
IF 14.3
Junce Wang,Jinfeng Chen,Ningning Liu,Jingjing Lei,Hong-Wen Gao,Fei Yu,Fanghui Pan,Jie Ma
Controlled synthesis and regulation of 2D nanomaterials with sufficient active sites are promising in electrochemical fluorine capture, but simultaneously achieving rapid rates and efficient activity of intercalation materials remains challengs. Herein, an integrated strategy of micro-regulation interlayer space and in situ modification of MXenes is proposed to enhance ion storage kinetics. The wedge-like microstructure of aluminum oxide/incomplete-Ti 3 C 2 T x MXene (Al 2 O 3 /i-Ti 3 C 2 T x ) is constructed by incomplete etching MAX and in situ derivation of A-layer element, in which the sub-nanoscale interlayer space is conducive to the small size ions intercalation, and the formation of “nanopump-like” effect boosted the ions diffusion. As evidenced by simulation calculations, Al 2 O 3 nanoparticles not only shorten the migration distance of electrons/hydrated ions in interlayers but also contribute a lower adsorption energy barrier, bringing excellent capture kinetics and stability. Benefiting from the interfacial conversion-intercalation pseudocapacitance, such electrode is endowed with a high defluoridation capacity (69.9 mg g −1 at 1.6V) and an outstanding instantaneous adsorption rate (9.51 mg g −1 min −1 ), and shows satisfactory stability in more than 200 cycles. The physicochemical coupling strategy opens a novel approach to optimizing the interlayer structure and in situ modification interface of MXene, which also provids a universal idea for efficient capture of varisized ions of intercalation materials.
研究领域:
材料科学
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环境科学
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DOI
PubMed
高影响因子
APPLIED SURFACE SCIENCE
·
2023
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IF 6.7
Shaomeng Huang,Xueyang Zhang,Liping Wang,Dan Li,Can Zhang,Lei Yang,Qiongqiong He,Bin Gao
Hydroxyapatite (HAP) is one of the fluoride adsorbents to remove fluoride in water, but F - is hard to enter the lattice of HAP caused by spatial confinement and competitive adsorption, which leads to low defluoridation efficiency. In this study, Ca-deficient regulation method was used to create ion channels during HAP synthesis to overcome the inhibition caused by spatial confinement effect, which increased the defluoridation capacity by 50 % from 1.56 to 2.34 mg/g (Initial F - concentration: 5 mg/L). The effects of dosage, pH, initial F - concentration and co-existing ions on defluoridation process were evaluated and the dosage of 1.4 g/L under neutral condition was the economic condition. The adsorption performance followed the Pseudo-second-order kinetic model and Freundlich isotherm model, which was a spontaneous and endothermic process. The results of molecular mechanics and density functional theory (DFT) calculations showed ion channels near the F - adsorption sites on HAP surface were generated due to the calcium deficiency, which effectively promoted F - into the lattice. The defects also changed the adsorption energy and sites of HF and F - , which reduced the competitive adsorption. In addition, the catalytic decomposition of HF molecules occurred on the surface of HAP was discovered for the first time.
研究领域:
环境科学
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材料科学
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DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2023
·
IF 13.6
Chengyi Wang,Yangbo Qiu,Chao Wang,Yubo Xu,Long-Fei Ren,Jiahui Shao
Fluoride (F − ) pollution in groundwater is an important environmental issue and capacitive deionization (CDI) holds promise for defluorination at moderate concentrations (e.g., 200 −1000 mg L −1 ). However, existing electrodes suffer from the overlap of electrical-double-layer (EDL) and severe co-ion effects at low (e.g., <200 mg L −1 ) and high sodium fluoride (NaF) concentrations (e.g., >1000 mg L −1 ), respectively, exhibiting poor salt adsorption capacity (SAC). Hence, a three-layer structured electrode, “membrane/carbon nanotube (CNT)/activated carbon (AC)” (CNT-MCE), was prepared through electrospinning CNT onto AC, followed by a polymer membrane coating. Compared to AC and membrane coated electrode, CNT-MCE with mesopore-dominated structure prevented EDL overlap, achieving a higher SAC of 40.8 mg g −1 at 100 mg L −1 NaF. At 1500 mg L −1 NaF, the positively charged CNT-MCE exhibited an improved SAC of 58.8 mg g −1 by inhibiting co-ion effects. Meanwhile, CNT-MCE consistently demonstrated superb SACs at 200 − 800 mg L −1 NaF and maintained excellent stability over a wide concentration gradient by inhibiting severe oxidation. Notably, CNT-MCE successfully decreased the F − concentration in simulated groundwater from 3.4 to 1.1 mg L −1 . Overall, our work provides an efficient strategy of electrode design to broaden the applicability of CDI for groundwater defluorination over a wide concentration gradient.
研究领域:
环境科学
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材料科学
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DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）