Environmental Pollutants and Bioavailability
·
2019
·
IF 0
Xiaona Li,Yang Song,Yongrong Bian,Fang Wang,Chenggang Gu,Xinglun Yang,Xin Jiang
The effect of oxalic acid on phenanthrene sorption was varied from that on pyrene sorption. 1.0 mg L-1 of oxalic acid inhibited phenanthrene sorption, whereas 20, 50 and 100 mg L-1 of oxalic acid enhanced the sorption. However, pyrene sorption onto biochar was all inhibited among different concentrations of oxalic acid. New functional groups and increased polarity were observed in the biochar coexisted with oxalic acid, moreover, a high concentration of oxalic acid led to an increased specific surface area of the biochar. These changed factors contributed to biochar sorption to phenanthrene, which was dominated by surface adsorption. Weakened aromaticity and increased release of dissolved organic carbon from biochar may have been the main reason for inhibited pyrene sorption onto biochar by oxalic acid. Therefore, this study suggested that root exudates could greatly influence the sorption behavior of biochar towards PAHs in soil rhizosphere, which deserves attention in agricultural systems.
研究领域:
环境科学
·
农业科学
✓ 已验证
产品关联
DOI
JOURNAL OF MOLECULAR LIQUIDS
·
2019
·
IF 4.561
Guoli Chen,Kun Song,Xiaoming Huang,Wenbo Wang
Titanium dioxide (TiO 2 ) colloid was synthesized by using tetrabutyl titanate . TiO 2 (KH-570) intermediate was prepared by etherification reaction of TiO 2 colloid and KH-570. The CS-GMA intermediate was prepared by ring-opening reaction of chitosan (CS) and glycidyl methacrylate (GMA). Finally, copolymerization two intermediates obtain a new adsorbent, TiO 2 (KH-570)-g-(CS-GMA). The results manifest that the maximum adsorption amounts of toluene and Pb(II) are 56.62 mg/g and 623.56 mg/g, respectively. The adsorption of TiO 2 (KH-570)-g-(CS-GMA) adsorbent for toluene and Pb(II) accord with the pseudo-second-order kinetics mechanism and Langmuir equation, indicate that the TiO 2 (KH-570)-g-(CS-GMA) adsorbent has better adsorption effect on toluene and Pb(II).
研究领域:
环境科学
·
材料科学
·
化学工程
·
污染控制
·
吸附技术
✓ 已验证
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2017
·
IF 4.233
Chenhu Zhang,Sun Wei,Yuehua Hu,Honghu Tang,Jiande Gao,Zhigang Yin,Qingjun Guan
Selective adsorption of tannic acid (TA) on calcite surfaces and the implications of this process for the separation of fluorite ore were studied by microflotation tests, surface adsorption experiments, zeta potential measurements, UV–vis analysis, and X-ray photoelectron spectroscopy (XPS) analysis. The microflotation tests indicated that TA, when added before sodium oleate (NaOl), could selectively depress calcite from fluorite at pH 7. Surface adsorption experiments revealed that TA hinders the interaction of NaOl with calcite. The zeta potential of calcite became more negative with TA than with NaOl. However, the characteristic features of TA adsorption were not observed on fluorite, suggesting that the dominant adsorption sites are dissimilar on the fluorite and calcite surfaces in the pulp. UV–vis spectroscopy, XPS, and solution chemistry analysis were utilized to obtain a better understanding of the mechanism for selective adsorption of TA as well as the key factors determined by the Ca 2+ and Ca(OH) + components on the mineral surfaces. A possible adsorption mechanism along with an adsorption mode is proposed for the surface interaction between TA and calcite.
研究领域:
矿物加工工程
·
表面化学
·
胶体与界面科学
·
资源利用
·
浮选化学
✓ 已验证
DOI
高影响因子
MATERIALS LETTERS
·
2018
·
IF 2.687
Huan Zhou,Ying Yang,Mengmeng Yang,Wenjie Wang,Yaping Bi
Mesoporous hydroxyapatite is widely applied in biomedical and environmental fields due to its high surface area and adsorption capacity. In current work a one-step hydrothermal method to synthesize mesoporous HA was developed with the assistance of a cost-effective template vitamin C. It was observed the pore size and morphology of hydrothermally synthesized HA were correlated to applied solution composition. A combination of calcium hydroxide, orthophosphate, and vitamin C can finally result in mesoporous rod-like HA nanoparticles with surface area of 88 m 2 .g −1 and pore size of 15.7 nm on average. The mesoporous HA exhibited enhanced adsorption of model drug doxorubicin in comparison to conventionally synthesized HA as expected. Consequently, this work provides new pathway to prepare mesoporous HA with advantages of economy and convenience.
研究领域:
生物材料学
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纳米医学
·
药剂学
·
环境科学
·
生物无机化学
✓ 已验证
DOI
高影响因子
JOURNAL OF CHEMICAL AND ENGINEERING DATA
·
2018
·
IF 2.196
Li Zhang,Fangxiang Song,Yonggui Wu,Liang Cheng,Jin Qian,Shuai Wang,Qianlin Chen,Yan Li
In this study, the as-prepared spherical mesoporous silica was modified by amino and cyano groups via grafting, and the amino and carboxyl functionalized adsorption materials (MSS@NH2@COOH) were obtained after cyano group hydrolysis. The introduction of amino and carboxyl groups increases the surface active sites of the materials. The materials were characterized by SEM, TEM, XRD, N2 adsorption/desorption, XPS, etc. BET analysis revealed the amino and carboxyl functionalized mesoporous silica maintained their mesostructure nature and its specific surface area was 113 m2·g–1. TG-DTA and FT-IR confirmed effective grafting on the surface of mesoporous silica with functionalized groups. The simulated wastewater of Ni(II) was carried out to test the adsorption properties of the materials, and several influential factors (pH, initial nickel ion concentration, adsorbent dose) were discussed. The saturated adsorption capacity increased clearly from 46.55 mg·g–1 of MSS to 125.57 mg·g–1 of MSS@NH2@COOH. Even recycling three times, the removal rate of Ni(II) ions using MSS@NH2@COOH as an adsorbent could still be over 75%. Adsorption isotherms, kinetics, and thermodynamics of adsorption were taken to clarify the adsorption process. This newly developed adsorbent material does exhibit good reusable performance and effective removal of the heavy metal ions of Ni(II).
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2022
·
IF 5.518
Yawei Shi,Guobin Song,Anqi Li,Jun Wang,Haonan Wang,Ya Sun,Guanghui Ding
A series of composite aerogels with different precursor mass ratios were prepared from graphene oxide (GO) and chitosan (CS) by conducting the crosslinking step after lyophilization, the method of which was recently found beneficial to enhance the adsorptive properties of aerogels . The composite aerogels were then employed for the adsorption of methyl orange (MO) and methylene blue (MB) from water, and the one prepared at GO:CS= 1:2 (w/w) was selected as the optimal compromising the adsorption and mechanical properties. The maximum adsorption amounts of MO and MB were calculated to be 543.4 and 110.9 mg/g at 25 °C. Especially, the effects of pH on adsorption of MO and MB in both single and binary systems were investigated in detail. The aerogel possessed pH-responsive feature for single dye adsorption, tending to adsorb MO at low pH while to adsorb MB at high pH. In the binary system, the pH-responsive feature remained and selective adsorption was observed at low initial dye concentration. In contrast, synergistic adsorption occurred instead at high initial concentration, and MB and MO could be efficiently removed simultaneously in the whole pH range of 3–11.
研究领域:
环境科学
·
材料科学
·
化学工程
·
水处理
·
吸附技术
✓ 已验证
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2022
·Vol. 139
·期 21
·52199
·
IF 3.057
Wenjiao Wang,Mingming Zheng,Jiajia Ren,Mingliang Ma,Xunqian Yin,Tingxi Li,Yong Ma
Magnetic Fe 3 O 4 /MnO 2 /TiO 2 /polypyrrole (PPy) heterostructure as adsorbent for adsorbing Mn 7+ was synthesized by combining hydrothermal method and chemical oxidation method. The heterostructure was characterized by field-emission scanning electron microscope, Fourier transform infrared spectroscopy, X-ray diffraction, and vibrating sample magnetometer. Its saturation magnetization is 18.88 emu/g, so it is easy to separate it from the solution. The feasibility of Fe 3 O 4 /MnO 2 /TiO 2 /PPy heterostructure to remove Mn 7+ was researched in detail. It is found that the optimal pH is 2. The initial adsorption rate can reach 4.60 mg/g min. At 288.15 K, the maximum equilibrium adsorption capacity is 202.8 mg/g. Adsorption kinetics follows a pseudo second order model, as well as is determined by through membrane diffusion processes. The Langmuir isotherm model is used to describe the adsorption isotherm behavior. Besides, thermodynamic parameters indicate spontaneous adsorption behavior, and entropy of the endothermic reaction increases. Finally, the cycle test results show that the adsorbent has better cycle performance, displaying broad application prospects.
研究领域:
环境科学
·
材料科学
·
化学工程
·
纳米技术
·
污染控制
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2021
·
IF 6.707
Huaxia Li,Wencui Chai,Yijun Cao,Shichong Yang
Surface pretreatment on minerals prior to flotation was proved to increase the selectivity of separation process. Organic acid pretreatment of low-grade diasporic-bauxite was conducted, and the effects of oxalic acid on bauxite flotation were investigated in this work. The oxalic acid pretreatment mechanisms were studied by adsorption measurements, zeta potential testing, XPS analysis, and ICP analysis. The flotation results showed that the oxalic acid treatment could significantly improve Al 2 O 3 recovery from 75.39% to 81.88% and decrease SiO 2 recovery from 53.26% to 47.30%. The adsorption capacity of diaspore for sodium oleate (NaOL) increased by 8.50%, while that of kaolinite decreased by 11.72%. XPS analysis revealed that oxalic acid treatment improved the relative contents of unsaturated Al at diaspore surface beneficial to the adsorption of NaOL. While the relative content of Al at kaolinite surface was decreased due to the Al dissolution revealed by ICP results. Zeta potential analysis indicated that oxalic acid changed the surface property of minerals favorable for the selective adsorption of NaOL on diaspore surface rather than kaolinite surface. These findings provided a promising direction for surface pretreatment of low-grade bauxite using oxalic acid for the improvement of the flotation desilication.
研究领域:
矿物加工工程
·
表面化学
·
资源综合利用
·
浮选化学
·
冶金工程
✓ 已验证
DOI
高影响因子
JOURNAL OF MOLECULAR CATALYSIS B-ENZYMATIC
·
2016
·
IF 2.189
Chen Chen,Xue-yan Zhu,Qiao-ling Gao,Fei Fang,Li-wei Wang,Xiao-jun Huang
Functional polyphosphazene cyclomatrix microspheres (PMS) containing glucose and dodecyl moieties were utilized for physical adsorption of lipase. In this regard, Candia Rugosa lipase was immobilized onto the above microspheres through physical adsorption, which exhibited catalytic hydrolysis of glycerol triacetate as the model reaction. As observed under transmission electron microscope (TEM) and scanning electron microscope (SEM), the size of all the microspheres ranged from 400 nm to 1 μm with a mean diameter of 680 nm. Zeta potential analysis demonstrated that the microspheres were negatively charged. The influences of buffer pH, substrate concentration and temperature were also studied along with reusability. The obtained results demonstrated that the immobilized lipase on deprotected glycosylated PMS (D-GPMS) showed the best performance and possessed the highest enzymatic loading activity around 1.0884 mmol L −1 min −1 g −1 , and retained nearly 50% of its initial activity even after 10 cycles of application. Moreover, the lipase-microsphere complex displayed high pH adaptability from 7 to 9 and temperature stability above 40 °C. From the viewpoint of biocompatible PMS support, the GPMS-lipase conjugate have potential applications in field such as food, medicine and environment.
研究领域:
生物材料
·
酶工程
·
纳米医学
·
分子生物学
·
环境生物技术
✓ 已验证
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2018
·
IF 2.829
Yueyun Fang,Qizhang Huang,Pengyi Liu,Jifu Shi,Gang Xu
This study demonstrated high-efficient dye adsorption for wastewater using MoS 2 -glue sponge as an easy-separative and regenerative adsorbent. Flower-like molybdenum disulfide (MoS 2 ) nanopowders with rich polar edge sites were firstly synthesized by a facile one-pot hydrothermal method . Chemical and morphological features of MoS 2 nanoflowers were then examined by XRD , XPS , SEM and TEM . Afterwards, different concentrations of the MoS 2 -glue sponges with easy separability were successfully fabricated by a convenient two-step dip-coating method. The adsorption performance was estimated by the removal of Rhodamine B (RhB) dyes. The results proved that the maximum adsorption capacity of MoS 2 -glue sponge was 127.39 mg RhB/g product in 60 min. The RhB uptake behaviors can be well described by the Sips isotherm model and pseudo-second-order kinetic model , indicating a multilayer and chemical adsorption process. The adsorption mechanism proposed that the zwitterionic RhB molecules in aqueous solution would aggregate on the surface of negative charged MoS 2 in a head-to-tail way through electrostatic interaction . Furthermore, RhB dyes could desorb easily from MoS 2 -glue sponges when changing the polarity of solvent and the reusability experiment showed that the MoS 2 -3% glue sponge could be reused for 15 times with above 85.8% of the adsorption capacity retained. Thus, the novel MoS 2 -glue sponge is considered as a competitive adsorbent for treatment of dyestuff waste water.
研究领域:
环境科学
·
材料科学
·
纳米技术
·
化学工程
·
水污染控制
✓ 已验证
DOI
高影响因子
RSC Advances
·
2015
·Vol. 5
·期 118
·97435-97445
·
IF 3.84
Yuling Cai,Liuchun Zheng,Zhanqiang Fang
To reduce costs and improve practicability, an ion imprinted magnetic chitosan (IMCS) was synthesized through co-precipitation using steel pickling waste liquor and chitosan and Cu(II) as template ions, which was then characterized by TEM, SEM, EDX, FTIR, XRD and VSM. The batch experiments were carried out for its potential application and high selectivity of Cu(II) removal, which were observed due to the paramagnetic properties and coordination reactions in the imprinted cavities. Kinetic studies revealed that the adsorption process followed a pseudo second-order model and the equilibrium data fit perfectly with the Langmuir isotherm model. The maximum adsorption capacity was 109.89 mg g−1. Negative values for ΔH0 and ΔG0 indicated an exothermic and spontaneous adsorption process. The adsorption process was found to be a chemical reaction and coordination complexes were formed between the metal ions and the groups of chitosan binding mainly in the “bridge model”. Moreover, 0.2 mol L−1 HCl solution was considered as the most appropriate eluent for regeneration. It showed a great performance in the experiments for practical copper wastewater and the process was considerably cost-effective.
研究领域:
环境化学
·
材料科学
·
污染控制工程
·
资源循环利用
·
吸附技术
✓ 已验证
DOI
高影响因子
ENVIRONMENTAL POLLUTION
·
2015
·
IF 4.143
Yan He,Fanfeng Zeng,Zhenghua Lian,Jianming Xu,Philip C. Brookes
Natural soil montmorillonite and kaolinite nanoparticles (NPs) were tested as efficient sorbents for organic contaminant (OC) removal through mimicking their natural environmental dispersive states. Sorption of both mineral NPs decreased with increasing pH with ionizable pentachlorophenol (PCP), but increased with pH with non-ionizable phenanthrene (PHE), within the pH range of 4–10. In contrast, sorption decreased consistently for both PCP and PHE, as a function of increasing ion concentration (0.001–0.1 mol L −1 ). Sorption differences were likely caused by the electrolytic conditions dependent upon surface chemistry of OCs and mineral NPs. The results confirmed that the highly dispersive soil mineral NPs would prevail over both engineered NPs and their regular μm-sized colloids for OC removal, due to their ecological advantages and higher sorption properties. This finding provided a realistic assessment of the environmental function of soil natural minerals in water once they are released from soil into OC polluted aqueous systems.
研究领域:
环境科学
·
土壤学
·
环境化学
·
纳米地球化学
·
污染控制
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）