Nanomaterials
·
2021
·Vol. 11
·期 10
·2580
·
IF 5.076
Jien Ye,Yating Luo,Jiacong Sun,Jiyan Shi
The aggregation of nanoscale zero-valent iron (nZVI) particles and their limited transport ability in environmental media hinder their application in environmental remediation. In this study, the Cr(VI) removal efficiency, transport performance, and toxicity of nZVI and bentonite-modified nZVI (B-nZVI) were investigated. Compared with nZVI, B-nZVI improved the removal efficiency of Cr(VI) by 10%, and also significantly increased the transport in quartz sand and soil. Increasing the flow rate can enhance the transport of nZVI and B-nZVI in the quartz sand columns. The transport of the two materials in different soils was negatively correlated with the clay composition. Besides, modification of nZVI by bentonite could reduce toxicity to luminous bacteria (Photobacterium phosphereumT3) and ryegrass (Lolium perenneL.). Compared with Fe-EDTA, the transfer factors of nZVI and B-nZVI were 65.0% and 66.4% lower, respectively. This indicated that although iron nanoparticles accumulated in the roots of ryegrass, they were difficult to be transported to the shoots. The results of this study indicate that B-nZVI has a strong application potential in in situ environmental remediation.Keywords:nanoscale zerovalent iron (nZVI);hexavalent chromium;bentonite;toxicity
研究领域:
环境科学
·
化学
·
纳米技术
✓ 已验证
DOI
PubMed
高影响因子
APPLIED CLAY SCIENCE
·
2021
·
IF 5.467
Lei Wang,Haris Muhammad,Minwang Laipan,Xiaohu Fan,Junkang Guo,Yongtao Li
The demand for clean water and soil drives high efficiency, less expensive, and eco-friendly clay-composites as adsorbents for remediation of heavy metals polluted environment. We have developed a new water remediation technique by using an organic-inorganic composite, L-cysteine doped polypyrrole modified bentonite (L-cys/PPy/BT) for removal of Cr(VI) and Mo(VI). The L-cys/PPy/BT showed maximum adsorption capacities of 318.5 and 65.4 mg/g for Cr(VI) and Mo(VI) respectively. For Cr(VI) and Mo(VI) the sorption process on L-cys/PPy/BT followed the Freundlich and Langmuir isotherm models, respectively. Furthermore, the pseudo-second-order kinetic model described the adsorption behavior of Cr(VI) and Mo(VI). Moreover, the thermodynamic parameters indicated that sorption processes were endothermic and spontaneous. Mechanistic assessment revealed that adsorption of Mo(VI) on L-cys/PPy/BT could be attributed to chelation, electrostatic attraction and ion-exchange of Mo(VI) with the imine/amine functional groups in the material's matrix , while electrostatic attraction, ion exchange, chelation and redox reaction played a significant role in the removal of Cr(VI). This research provides a new approach for the use of clay materials as potential sorbents for removal of heavy metal ions in contaminated water .
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2021
·
IF 7.963
Junzhi Yu,Zhansheng Wu,Xiongfang An,Fei Tian,Bing Yu
The stability of biochar is a crucial parameter in determining the potential of biochar for carbon sequestration . Many studies have demonstrated that the addition of clay during the pyrolysis of biomass is beneficial for the production of biochar with a high stability, but finding a strategy for a further improvement of stability of clay-modified biochar is still highly desirable. Herein, the co-pyrolysis of biomass and clay mediated by trace metal elements is proposed as a new strategy for the production of biochar with exceptionally high stability. The results indicate that the biochar resistance index for biochar obtained from the trace metal elements mediated the co-pyrolysis of biomass and clay is ~0.75, which is much higher than that of biochars obtained from biomass pyrolysis or the co-pyrolysis of biomass and clay, demonstrating that the presence of metal ions during the co-pyrolytic process can significantly improve the oxidation resistance of biochar. Thermogravimetric analysis reveals that the carbon retention value is reduced when the addition of metal ions during the co-pyrolytic process, and the presence of metal ions can reduce the starting temperature of the pyrolysis reaction and catalyze the process of biomass pyrolysis. In addition, the percentages of C C, C C, and C H in all biochars obtained from trace metal elements mediated the co-pyrolysis of biomass and clay are greater than 41.82%, which are higher than that of original biochar. Besides, the percentage of oxygen-containing functional groups is found to be decreased after the presence of metal ions during the co-pyrolytic process. The presence of metal ions can form metal nano-sulfides and oxides on the surface, which plays a physical barrier to the anti-oxidation performance of biochar. Furthermore, compared to BBC or BC, MnBBC and ZnBBC have a better leaching resistance to P, while FeBBC has almost no leaching resistance to soil P. Overall, the study reveals that the addition of trace element metal ions during the co-prolysis of biomass and bentonite is an effective method to increase the stability of obtained biochar, and it is also beneficial for retarding the release of nutrients in the soil and thus increase the utilization of nutrients.
研究领域:
环境科学
·
土壤学
✓ 已验证
DOI
高影响因子
JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY
·
2024
·
IF 1.5
Tian Yunting,Li Yongmei,Tan Kaixuan,Li Chunguang,Li Xiaojie,Liu Wei,Tang Zhipeng,Liu Longcheng
Bentonite colloids and fluid velocity significantly influence the migration behavior of the redox sensitive nuclide Se(IV) in the disposal repository. In this study, the migration behavior of Se(IV) in artificial fracture, which was created by Beishan granite and polyethylene pipe, was studied under reduced condition, with Br − as a tracer. The effects of bentonite colloids and fluid flow rate on the migration of Se(IV) in the fracture were explored. The results show that a part of Se(IV) would adsorb on the surface of granite in reduced condition. The maximum penetration rate of Se(IV) increases with the decrease of water flow rate. In addition, the colloids hindered the migration of nuclide Se(IV) in the fissure to some extent during the process of co-migration.
研究领域:
环境科学
·
放射性废物管理
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2024
·
IF 7.7
Irfan Ijaz,Aysha Bukhari,Ezaz Gilani,Ammara Nazir,Hina Zain,Attia Shaheen,Mohammed Rafi Shaik,Mujeeb Khan,Mohamed E. Assal
A rising quantity of drugs has been discharged into the aquatic environment, posing a substantial hazard to public health. In the current work, a novel hydrogel (i.Carr@Bent@PTC), comprised of iota-carrageenan, bentonite, and 4-phenyl-3-thiosemicarbazide, was successfully prepared. The introduction of 4-phenyl-3-thiosemicarbazide and bentonite in iota-carrageenan significantly increased the mechanical strength of iota-carrageenan hydrogel and improved its degree of swelling, which can be attributed to the hydrophilic properties of PTC and Bent. The recorded contact angle was 70.8°, 59.1°, 53.9°, and 34.6° for pristine i.Carr, i.Carr@Bent, and i.Carr@Bent@PTC, respectively. The low contact angle measurement of the Bent and PTC loaded-i.Carr hydrogel was attributed to the hydrophilic Bent and PTC. The ternary i.Carr@Bent@PTC hydrogel demonstrated broad pH adaptability and excellent adsorption capacities for sulfamethoxazole (SMX) and losartan potassium (LP), i.e., 467.61 mg. g −1 and 274.43 mg. g −1 at 298.15 K, respectively. The pseudo-first-order (PSO) model provided a better fit for the adsorption kinetics . The adsorption of SMX and LP can be better explained by employing the Sips and Langmuir isotherm models. As revealed by XPS and FTIR investigations, π-π stacking, complexation, electrostatic interaction , and hydrogen bonding were primarily involved in the adsorption mechanisms.
研究领域:
环境科学
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材料科学
·
药物化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
·
2026
·
IF 7.8
Jinsuo Ma,Qian Ma,Qi Wang,Yu Li,Wenxin Ji,Yulong Ma,Yonggang Sun,Yuanyuan Li
To address the critical limitations of natural bentonite, including restricted specific surface area and low cation exchange capacity (CEC) caused by interlayer impurities, this study proposes an in situ structural reconstruction strategy via simultaneous alkaline activation and aluminum doping. This approach directly transforms bentonite frameworks into a hierarchically porous SOD-type sodalite with an ultralow Si/Al ratio. The engineered material integrates three synergistic advantages: abundant surface hydroxyl groups, maximized CEC (saturation capacity, 242.56 mg/g), and a dual-scale pore architecture (micropores/mesopores). Combined experimental and computational analyses reveal the underlying mechanisms: The ultralow Si/Al ratio generates Al–O–Si bridging sites, strengthening electrostatic interactions with Pb2+ (adsorption energy: −1.356 eV) and reducing the migration energy barrier. Local charge redistribution at Al-rich domains optimizes Pb2+ occupation, achieving a stable Pb–O bond length of 2.35 Å. Hierarchical porosity facilitates rapid mass transfer, enabling 93% adsorption capacity retention after eight regeneration cycles. This work establishes a quantitative structure–performance relationship among Si/Al ratio, charge distribution, and adsorption efficiency through bentonite interlayer reconstruction. It provides fundamental insights for designing high-performance, low-cost heavy metal adsorbents, demonstrating a 2.7-fold increase in Pb2+ uptake compared to conventional bentonite, developing high-performance, low-cost heavy metal adsorbents.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
DESALINATION
·
2024
·
IF 8.3
Hao Wang,Yue Zhu,Bin Hu,Jianmao Yang,Jianyun Liu
Conventional carbon electrodes possess low desalination capacity and poor cycling stability, while faraday electrode materials are not economical with limited resource for capacitive deionization (CDI) technology. Therefore, exploring new type of electrode materials with high desalination capacity, low cost and excellent cycle stability is highly desirable. Bentonite (Bent) is an excellent ion-exchange material, with high natural abundance, super stability, but it has low conductivity. In this paper, a nitrogen-doped carbon modified Bent (NC@Bent) was prepared by in-situ polymerization of dopamine on the surface of Bent followed by carbonization . The N,C-modified thin layer on Bent improved the conductivity, boosting the charge transportation and ion diffusion. The NC@Bent was used as ion-adsorption electrode, exhibiting excellent electro-adsorption behavior. In a rocking-chair CDI (RCDI) cell, it delivered an extraordinary desalination capacity of 82 mg g −1 and super cycling stability with 90 % capacity retention in 50 cycles. Finally, the total dissolved salts in the actual groundwater were effectively reduced by using the current RCDI cell, meeting the WHO recommendation for drinking water . In consideration of the unique feature of low-cost and non-toxicity of Bent, this ion-exchange electrode material (NC@Bent) has much potential for drinking-water purification.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
Results in Surfaces and Interfaces
·
2024
·
IF 0
Alimoh Helen Alabi,Kelechukwu Kelvin Ibe,Paul Abi,Clement Ajibade Olanrewaju,Peter Olusakin Oladoye,Kehinde Shola Obayomi
Adsorption is a suitable technique for decontamination of organic dye wastewaters. Herein, we comparatively investigated the adsorption performance of bentonite (BEN) and its modification with groundnut shell (BGS) and palm kernel shell (BPS) for methylene blue (MB) and congo red (CR) dyes removal from aqueous solution. BGS and BPS were prepared by calcination at 300 °C for 6 h and were characterized using BET, SEM, EDS and FTIR to determine their textural properties, morphologies, elemental compositions, and functional groups. The BET surface examination revealed that the surface area of BEN was enhanced from 78 m 2 /g to 195 m 2 /g and 141 m 2 /g after modification with groundnut shell (BGS) and palm kernel shell (BPS), respectively. The adsorption process in a batch system was subjected to comprehensive experimentation to investigate the effect of adsorbent dosage, contact time, temperature, initial concentration, and pH. The adsorption was fitted to adsorption isotherm and kinetic models and the results revealed that the adsorption process of BEN, BGS, and BPS towards MB and CR adsorption can be best described by Temkin, Freundlich and pseudo-second order kinetic models. The adsorption capacities ( q max ) for uptake of MB by BEN, BGS and BPS are 10.61, 10.85 and 10.93 mg, while CR exhibited 8.83, 6.87 and 5.86 mg/g, respectively. The thermodynamics study revealed that the adsorption process was spontaneous, feasible, endothermic in nature. The adsorption process is governed by electrostatic attraction with the involvement of physical and chemical adsorption. This study suggests that biomass-modified bentonite is a sustainable, cost-effective, non-toxic, and greener approach for eliminating MB and CR from aqueous solution. Furthermore, the modification method does not only achieve substantial removal of MB and CR dyes, but also offers considerable energy savings and operational cost reductions in real-time based on water quality data. This study does present a novel, sustainable approach to improve natural water treatment efficiency and compliance.
研究领域:
环境科学
·
材料科学
·
化学工程
✓ 已验证
DOI
Journal of Environmental Chemical Engineering
·
2017
·
IF 0
Jinming Hua
Inorgano–organo–bentonite (PMBt) was synthesized through co-modification of bentonite with manganese oxides and poly(dimethyldiallylammonium chloride) (PDMDAAC), and was utilized to remove low-concentration arsenic from water. The hybrid material was characterized by means of X-ray powder diffraction (XRD), scanning electron microscopy (SEM) and N 2 adsorption–desorption. It was revealed that the hybrid material possessed an amorphous structure and displayed uneven manganese oxides particles gathering about the bentonite aggregates with a large BET area of 128.90 m 2 /g. The effects of adsorption parameters were investigated, such as stirring time, arsenic concentrations, adsorbent dose, temperature, pH, added anions and ionic strength. The adsorption kinetics and equilibrium of arsenic on the co-modified bentonite were further determined. The results revealed that the adsorption of arsenic was dramatically affected with change in solution pH and significantly suppressed by phosphate anion. The adsorption kinetic data was best fitted with the linear pseudo–second–order model and was well with the non-linear Bangham model. The equilibrium data were well simulated with the Brunauer–Emmett–Teller, Freundlich and Redlich–Peterson isotherms by either non-linear or linear regression, respectively. The non-linear Langmuir isotherm showed best fitting and the maximal adsorption capacity was 9.14–9.99 mg/g, dependent on the error function used. It was suggested that the hybrid material had a heterogeneous surface and high affinity towards arsenic, which is highly favorable for arsenic adsorption following a non-ideal monolayer adsorption model. Based on the above comprehensive analysis, the plausible mechanism for arsenic adsorption on PMBt was suggested as a mixed removal mechanism i.e., electrostatic attraction followed by inner-sphere complexation.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
Applied Nanoscience
·
2019
·Vol. 10
·期 3
·775-786
·
IF 3.198
Jiang Jun,Hou Li,Lu Zhongyuan,Li Jun,Wang Jinxin,Yang Ying,Niu Yunhui
Nanosilica-modified swelled bentonite used as a pore-forming agent was introduced into cement pastes for the preparation of nanopore-rich lightweight cement pastes (NLCPs). The effect of nanosilica on the pore structure and hardened properties of NLCPs and their influence mechanisms were investigated. The results indicated that the introduction of nanosilica reduced pore size and improved nanopore content, due to increased platelets in voids, voids filled by hydration products and unreacted nanosilica. The percentage of nanopore content improved from 67.2 to 94.7% and 55.5–71.3% after, respectively, introducing a 60% and 80% bentonite slurry with increasing nanosilica replacement from 0 to 20%, and the median pore size decreased from 48.6 to 30.9 nm and 80.4–47.5 nm, respectively. The thermal insulation performance and compressive strength of NLCP were gradually enhanced by adding nanosilica from 0 to 20%. When nanosilica content was 20%, an increasing rate of 55.2% and 220.0% in 7-day compressive strength and 65.3% and 211.1% in 28-day compressive strength, with a 20.7% and 10.5% reduction in thermal conductivity at porosity of 61.3% and 72.3% can be achieved, respectively.
研究领域:
材料科学
·
土木工程
✓ 已验证
产品关联
DOI
高影响因子
CARBOHYDRATE POLYMERS
·
2016
·
IF 4.219
Xiaogang Luo,Xiaojuan Lei,Xiuping Xie,Bo Yu,Ning Cai,Faquan Yu
Many efforts have been driven to decontaminate the drinking water, and the development of efficient adsorbents with the advantages of cost-effectiveness and operating convenience for the removal of Pb 2+ from water is a major challenge. This work was aimed to explore the possibility of using cellulose-based adsorbents for efficient adsorption of Pb 2+ . The millimeter-scale magnetic cellulose-based nanocomposite beads were fabricated via an optimal extrusion dropping technology by blending cellulose with the carboxyl-functionalized magnetite nanoparticles and acid-activated bentonite in NaOH/urea aqueous solution, and then they had been tested to evaluate the effectiveness in the removal of Pb 2+ from water. The effects of contact time, initial heavy metal ion concentrations, adsorption isotherms and solution pH on the sorption behavior were studied. The thermodynamic parameters (Δ G , Δ H and Δ S ) indicated that the adsorption processes were feasible, spontaneous, endothermic and mainly controlled by chemical mechanisms. The reusability of the adsorbent was also studied.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2016
·
IF 3.138
Pan Hu,Jing Wang,Ruihua Huang
In this study, simultaneous removal of Cr(VI) and Amido Black 10B (AB10B) using quaternized chitosan coated bentonite was investigated by a batch method. The factors affecting adsorption process such as pH, adsorbent dosage, contact time and initial concentration and the interaction of two components in binary solutions have been studied. The results showed that the antagonism effect existed between Cr(VI) and AB10B in binary systems. The equilibrium time for Cr(VI) adsorption was less than the one for AB10B adsorption. The maximum adsorption capacities of the modified bentonite, according to the Langmuir isotherm model were 847.5 mg/g for AB10B and 66.6 mg/g for Cr(VI) at 298 K. The experimental results demonstrated that both Cr(VI) and AB10B were well described by the pseudo-second-order model. Thermodynamic study depicted that the adsorption of Cr(VI) and AB10B onto the modified bentonite was both spontaneous. The adsorption for Cr(VI) was exothermic while the one for AB10B was endoth- ermic in nature.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）