Environmental Pollutants and Bioavailability
·
2019
·
IF 0
Yuehui Tan,Xianqiang Yin,Caiyun Wang,Huimin Sun,Aisheng Ma,Guilong Zhang,Nong Wang
The Cd(II) adsorption of kiwi biochar functionalized with Mg-Fe (3:1) layered double hydroxides (LDH) was studied. And the biochar was got via liquid-phase deposition, by incorporating Mg-Fe layered double hydroxide (Mg-Fe LDH) particles into kiwi biochar (KB/LDH). The batch of sorption experiments were studied, including adsorption kinetics and isotherm and the effects of pH, ion strength (IS) and co-existing ions. The KB/LDH composite showed a strong sorption ability to Cd(II) in aqueous solutions with the adsorption capacity of 25.6 mg g−1, compared with pristine biochar of 1.78 mg g−1. The adsorption of Cd(II) on KB/LDH composite increased with the decreasing of IS, decreased first and then grew larger with the increase of pH and was observed irrespective of the co-existence of K+, Cl− and NO3−. To sum up, the KB/LDH can be potentially used as an alternative adsorbent to amend the water and soil contaminated by Cd(II).
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
Desalination and Water Treatment
·
2024
·
IF 1
Yulong Yang,Jiao Feng,Shicui Zhu,Jinshu Zhou,Kejia Zhang,Xiaoyan Ma,Danial Gallagher,Andrea M. Dietrich
Nitrogenous disinfection by-products (N-DBPs) are more genotoxic and cytotoxic than the currently regulated carbonaceous DBPs (i.e., C-DBPs), and it has become a frontier issue of drinking water safety research. In this paper, the effect of granular activated carbon (GAC) on adsorption and its influencing factors was investigated for a typical N-DBP phenylacetonitrile, which is produced during chlorination of phenylalanine precursor during water treatment. The results showed that GAC had a high adsorption capacity (q max = 22.92 mg/g) for phenylacetonitrile, and the adsorption isotherm was fitted to the Langmuir isotherm model. Pseudo-second-order equation can well describe the behavior of phenylacetonitrile adsorption on activated carbon (R 2 > 0.990), and the adsorption rate constant k 2 = 0.7780–14.12 g/(mg h). Analysis of the influencing factors showed that higher phenylacetonitrile concentration improved the adsorption equilibrium capacity and the adsorption rate. Water temperature and pH had little effect on the capacity or rate of adsorption.
研究领域:
环境科学
·
水处理工程
·
毒理学
·
环境健康
✓ 已验证
DOI
高影响因子
POLYMER DEGRADATION AND STABILITY
·
2018
·
IF 3.193
Anna Zheng,Yongkang Huang,Yang You,Jian Hu,Dafu Wei,Xiang Xu,Yong Guan
The heat resistance enhancement of fluorosilicone rubber (FSR) can make it more suitable for cutting-edge applications and extreme conditions. This paper focused on the antioxidant properties of boron particles for FSR and the corresponding mechanism. The thermal stability of FSR and FSR/boron composites was characterized by thermal gravimetric analysis (TGA), isothermal degradation and thermal-oxidative ageing. The results showed that boron significantly improved the thermal stability of FSR. In particular, the FSR/boron (100/10) composite retained 95% of its weight after isothermal degradation at 350 °C for 12 h, while the FSR lost 55% of its weight within the initial 1 h. The antioxidant mechanism of boron was further investigated by chemiluminescence (CL), electron paramagnetic resonance (EPR) and vulcanization curves. It was shown that boron has powerful radical scavenging activity (RSA) and inhibited the oxidation scission of the side groups. Moreover, boron revealed no RSA towards the tert-butoxy radical, ensuring the good vulcanization of the FSR/boron composites.
研究领域:
高分子材料科学
·
橡胶化学
·
功能复合材料
·
热稳定性能
·
抗氧化机制
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2020
·
IF 10.652
Mengdi Yuan,Chao Xu,Tieying Wang,Tianying Zhang,Xinyu Pan,Feng Ye
The serious supercooling of erythritol (ET) limits its application in the field of mid-temperature thermal energy storage (TES), especially in the recently developed form-stable phase change materials (PCMs). The primary purpose of this paper is to find out the factors to mitigate the supercooling of ET/expanded graphite (EG) form-stable composite PCM and obtain the correlation among the morphology, kinetic parameters, and a supercooling degree in the non-isothermal crystallization process. Firstly, five types of supercooling relaxation agents (nano-Al 2 O 3 , nano-SiO 2 , CMC, urea, and citric acid) were added to prepare the ET/EG form-stable CPCMs. Among them, the ET/EG/nano-Al 2 O 3 exhibited excellent form-stable ability, a high heat release ratio of 78.9%, and the lowest supercooling degree (Δ T ) of 45.7 °C. Based on the chosen ET/EG/nano-Al 2 O 3 CPCM, the tablet pressures from 1 to 13 MPa were applied, obtaining lowest Δ T decreased by 59.0% in 1 MPa. Moreover, the non-isothermal crystallization processes were discussed on the ET/EG/nano-Al 2 O 3 with the Avrami equation modified by Jeziorny. ET tended to grow spherulites under the high cooling rate of 18 °C/min with triggering as the Johnson-Mehl-Avrami exponent n increased to 4.22. Meanwhile, the supercooling degree increased from 48.8 to 56 °C with the cooling rate growing from 2 to 18 °C/min. And the activity energy Δ E of the ET/EG/nano-Al 2 O 3 CPCM (7092.35 kJ/mol) was smaller than that of the ET/EG CPCM (8211.19 kJ/mol) because of the interaction between the heterogeneous nucleation effect and blocker effect of nano-Al 2 O 3 .
研究领域:
材料科学
·
热能存储
·
物理化学
·
复合材料
·
能源材料
✓ 已验证
DOI
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
·
2021
·
IF 5.455
Zhe Zhang,Lei Xu,Yani Liu,Runtian Feng,Tong Zou,Yuanshuo Zhang,Yuru Kang,Pengxin Zhou
In order to improve the efficiency of the removal of methylene blue from wastewater, we synthesized activated carbon by thermally activating phosphoric acid-treated mangosteen peels. This activated carbon possessed a great specific surface area (1832 m 2 /g) and exhibited excellent adsorption capacity (871.49 mg/g) for methylene blue. In this study, we varied the impregnation ratios, activation temperatures, and activation time to determine the best conditions for preparing the mangosteen peel activated carbon (MPAC). The optimal conditions included a 1:3 impregnation ratio with activation for 60 min at 450 °C. We characterized the MPAC using a scanning electron microscope, powder X-ray diffraction, thermogravimetric analysis , differential scanning calorimetry , and Fourier transform infrared spectroscopy together with the Brunauer–Emmett–Teller approach. The adsorption experiment results conformed to the pseudo-second-order kinetic model and the Langmuir isotherm model. This proved that physical adsorption dominates in this adsorption process . The synthesized MPAC-5 showed great adsorption performance for a variety of dye wastewater. After three times of recycling, the removal rate of methylene blue is still above 40%. Compared with other biowastes, mangosteen peel has the potential to be synthesized into activated carbon with a high adsorption capacity for dyes.
研究领域:
环境科学
·
材料科学
·
化学工程
·
污染控制
·
吸附技术
·
废物资源化
✓ 已验证
DOI
高影响因子
RSC Advances
·
2018
·Vol. 8
·期 15
·8026-8038
·
IF 2.936
Shuli Liu,Zhengyang Duan,Changhua He,Xiaojun Xu,Tianguo Li,Yuhuan Li,Xuan Li,Yao Wang,Longqian Xu
Phosphate-modified baker's yeast (PMBY) was prepared, and used as a novel bio-sorbent for the adsorption of Pb2+ from aqueous solution. The influencing factors, absorption isotherms, kinetics, and mechanism were investigated. The scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR) characterization and elemental analysis of PMBY showed that phosphate groups were successfully grafted onto the surface of yeast. The kinetic studies suggested that the adsorption process followed a pseudo-second-order chemisorption. The adsorption process of Pb2+ using PMBY was spontaneous and endothermic. Furthermore, the adsorption of Pb2+ on PMBY can rapidly achieve adsorption equilibrium (in just 3 min), and the maximum adsorption capacity of Pb2+ on PMBY was found to be 92 mg g−1 at 30 °C, which was about 3 times that of the pristine baker's yeast. The suggested mechanism for Pb2+ adsorption on PMBY was based upon ion-exchange, electrostatic interaction and chelation between the phosphate groups and Pb2+. However, compared with the pristine baker's yeast, the higher capacity and rapid adsorption of PMBY for Pb2+ was mainly due to the chelation and electrostatic interactions between the phosphate groups and Pb2+. In addition, the regeneration experiments indicated that the PMBY was easily recovered through desorption in 0.01 M HCl, and that PMBY still exhibited 90.77% of the original adsorption capacity for Pb2+ after five regeneration cycles. These results showed the excellent regeneration capability of PMBY for Pb2+ adsorption. PMBY has shown significant potential for the removal of heavy metals from aqueous solution due to its rapid adsorption, high-capacity and facile preparation.
研究领域:
环境科学
·
生物化学
·
环境污染治理
·
重金属吸附
·
材料科学
✓ 已验证
DOI
高影响因子
International Journal of Electrochemical Science
·
2023
·Vol. 11
·期 12
·10135-10149
·
IF 1.5
Lijuan Gong,Kangquan Qiao
The corrosion inhibition performances of Diantipyrylmethane (DAM) for mild steel in 0.5 M H 2 SO 4 were investigated using weight loss, electrochemical impedance spectroscopy (EIS), potentiodynamic polarization, scanning electron microscope (SEM) and quantum chemical calculation. The obtained results reveal that DAM acts as a mixed-type inhibitor with a predominantly anodic reaction, and the inhibition efficiency increases with increasing inhibitor concentration whereas decreases with increasing temperature. The adsorption of DAM on steel surface is found to obey Langmuir isotherm, and the adsorption mechanism is mixed physical and chemical adsorption. The results of quantum chemical calculation demonstrate that pyrazolone rings within molecular structure of DAM play a dominant role in corrosion inhibition of mild steel.
研究领域:
材料腐蚀与防护
·
物理化学
·
电化学
·
表面科学
·
量子化学
✓ 已验证
DOI
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2019
·
IF 4.561
Qi Liu,Xiaoxiao Chen,Yan Guo,Chuanhong Han,Jing Li,Lihan Jia,Jie Liu,Xilian Wei
A ternary phase diagram of the system of 1-butyl-3-methylimidazolium tetrafluoroborate ([ Bmim ]BF4), sodium dodecylbenzenesulfonate (SDBS) and water using ocular estimate and turbidity method was drawn based on experimental data at 298.2 K. We got a narrow aqueous two-phase region near the side of water-ionic liquid (IL). A series of samples with different compositions around the phase diagram were chosen. The enthalpy change of these systems after injecting triply distilled water into these samples has been studied by using isothermal titration microcalorimetry (ITC). It is found that with increasing the water content there are weak endothermic and exothermic processes appearing, separately, which matches perfectly with the location of the formation and disappearance of the aqueous two-phase in the ternary phase diagram. This suggests the ITC is a feasible and effective method for the thermodynamic study of aqueous two-phase systems (ATPS) and was first reported. The experimental results show that the formation of the ATPS is endothermic (Δ H > 0), but the process of disappearing is exothermic (Δ H < 0). Due to the formation of aqueous two-phase is a thermodynamic spontaneous process under the isothermal constant pressure, we can judge that the formation of this ATPS is an entropy driven course and the vanishing is a synergy driven process by entropy and enthalpy.
研究领域:
物理化学
·
热力学
·
胶体与界面化学
·
分离科学
·
分析化学
✓ 已验证
DOI
高影响因子
RSC Advances
·
2016
·Vol. 6
·期 79
·75855-75861
·
IF 3.289
Qixuan Song,Hui Wang,Baoshan Yang,Fei Wang,Xinrong Sun
A novel silver nanoparticle-modified magnetic multi-walled carbon nanotube composite (Ag-FMWCNTs) was synthesized by embedding Fe3O4 and assembling Ag nanoparticles in one-step. The properties of the Ag-FMWCNTs composites and magnetic multi-walled carbon nanotubes (FMWCNTs) were studied by scanning electron microscopy, vibrating sample magnetometry (VSM) and Fourier transform infrared spectroscopy. The adsorption isotherms, adsorption kinetics and the effects of solution pH and ionic strength to adsorb emerging contaminant sulfamethoxazole (SMX) from aqueous solution on different multi-walled carbon nanotubes-based adsorbents were determined. The results showed that the adsorption kinetics could be explained well by means of the pseudo-second-order and intraparticle diffusion models. The pH experiments showed that maximum adsorption occurred at pH 4. Additionally, all adsorbents had a strong adsorption ability to SMX and the Langmuir maximum capacity followed the order: 5% Ag-FMWCNTs (118.58 mg g−1) > 3% Ag-FMWCNTs (86.41 mg g−1) > MWCNTs (73.69 mg g−1) > 1% Ag-FMWCNTs (70.26 mg g−1) > FMWCNTs (45.13 mg g−1). The spent adsorbents were regenerated in methanol. It was also found that after regenerating four times, multi-walled carbon composites retained up to 80% of their original adsorption performance. Therefore, the Ag-FMWCNTs composite could be used as a potential adsorbent for removing sulfamethoxazole from water.
研究领域:
环境科学
·
纳米技术
·
水污染控制
·
吸附材料
·
药物残留治理
✓ 已验证
DOI
高影响因子
FLUID PHASE EQUILIBRIA
·
2018
·
IF 2.197
Xiaopo Wang,Kai Kang,Shanshan Zhu,Bo Gao
In this work, experimental density data were reported for six fatty acid methyl esters , including methyl butyrate , methyl valerate , methyl caproate , methyl pelargonate , methyl heptanoate , and methyl caprylate . The densities were measured from 293.15 K to 363.15 K and pressures up to 60 MPa by a vibrating-tube densimeter . The relative uncertainty of the measurement is estimated less than 0.001 with a confidence level of 0.95. The high pressure densities were correlated with a Tait-type equation. The overall average relative deviation between experimental data and calculated results from Tait equation for the six fatty acid esters is 0.010%. The derived thermodynamic properties, such as isobaric thermal expansivity and isothermal compressibility , were obtained from the experimental density results. Additionally, for the studied esters, the molecular parameters of the PC-SAFT equation of state were obtained based on the corresponding vapor pressures and liquid densities. The PC-SAFT equation was used to predict the high pressure densities of the esters, and good agreements were observed.
研究领域:
化学工程
·
热力学
·
流体物理化学
·
生物燃料
✓ 已验证
DOI
高影响因子
Desalination and Water Treatment
·
2024
·
IF 1
Jian Wu,Dajun Ren,Shuqin Zhang,Wenting Liu,Xiaoqin Zhang,Xiangyi Gong
Organic pollutants in aqueous solutions may potentially be adsorbed on biochar. In this study, biochar was derived from the pyrolysis of chitosan at 800°C. The removal rate of 2,4-dichlorophenol (DCP) exceeded 80%. Investigations by Fourier transform infrared spectroscopy and Brunauer– Emmett–Teller indicated that the adsorption of organic pollutants on biochar tends to be a physical process. The optimized pH was 5. All three isotherm models involved (Freundlich, Koble–Corrigan, and Henry) could describe the adsorption process of 2,4-DCP well on chitosan-biochar, which was non-uniform surface adsorption in a diluted solution. The adsorption was an endothermic process. It took 40 min to reach the adsorption equilibrium, and kinetics of the Elovich equation and intraparticle diffusion (IPD) model indicated that the adsorption rate at the rapid adsorption stage was simultaneously controlled by surface diffusion and IPD and that at slow adsorption stage was controlled by surface diffusion. The ionic strengths suggested that electrostatic interaction was not the dominant mechanism during this process.
研究领域:
环境科学
·
环境工程
·
材料科学
·
污染控制化学
·
吸附技术
✓ 已验证
DOI
高影响因子
Desalination and Water Treatment
·
2024
·
IF 1
Hongyuan Qin,Jiawei Huang,Xueli Zhang,Ling Yu,Yang Yu
In this study, lanthanum hydroxide adsorbent was synthesized through a simple hydrothermal method and applied for removing phosphate from water. The optimal adsorbent was obtained at the La/OH molar ratio of 4:1. The adsorbent showed rapid adsorption of phosphate within the first 4 h in which approximately 84% of the equilibrium adsorption capacity can be achieved. The phosphate uptake was highly dependent on solution pH. The better fit of the Langmuir isotherm model to experimental data indicated that the monolayer adsorption occurred and the maximum adsorption capacity of 193.9 mg/g was accomplished at pH 7.0. The presence of fluoride could significantly retard the uptake of phosphate. X-ray photoelectron spectroscopy analysis indicated that hydroxyl groups on the adsorbent surface played the most key role in the adsorption. The phosphate ions were adsorbed on the adsorbent through the formation of inner-sphere complexes.
研究领域:
环境化学
·
纳米材料科学
·
水污染控制
·
表面化学
·
吸附科学
✓ 已验证
DOI
高影响因子