JOURNAL OF RARE EARTHS
·
2017
·Vol. 36
·期 3
·304-310
·
IF 2.429
Shengting Kuang,Zhifeng Zhang,Yanling Li,Haiqin Wei,Wuping Liao
The extraction and separation of heavy rare earths (REs) using newly synthesized α-aminophosphonic acid extractant 2-ethylhexyl-3-(2-ethylhexylamino)pentan-3-yl phosphonic acid (HEHAPP, H A ) in n-heptane were investigated from chloride medium. The extraction stoichiometries of lanthanum , gadolinium , yttrium and lutetium are determined to be RE A 3 by the slope analysis method. The favorable separation factors of adjacent heavy REs(Ⅲ), i.e. β Y/Ho , β Er/Y , β Tm/Er , β Yb/Tm and β Lu/Yb , are determined to be 1.87, 1.36, 3.21, 3.22 and 1.93, respectively, when extracted from a binary system at proper condition. The loading capacities of H A for Ho, Er, Yb and Lu increase in the order Ho < Er < Yb < Lu with the values being 0.201, 0.205, 0.216 and 0.229 mol/L, respectively. So H A would be a potential extractant for the separation of heavy REs(Ⅲ). Among inorganic acids such as H 2 SO 4 , HNO 3 and HCl, HCl is tested to be the most effective stripping agent.
研究领域:
湿法冶金
·
稀土化学
·
分离科学与技术
·
无机化学
·
萃取化学
✓ 已验证
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2019
·
IF 4.784
Shaojie Zhang,Chao Yu,Na Liu,Yun Teng,Cuiyu Yin
In this study, cellulose pulp and urea were used to synthesize cellulose carbamate (nitrogen content reaches 4.5%) by low-cost and environmentally friendly solid-liquid phase method. Cellulose carbamate fluid was prepared by using sodium hydroxide aqueous solution as solvent. The fluid was regenerated and formed in a coagulation bath , and finally a regenerated cellulose membrane with high transparency and separation ability was obtained. The simple chemical treatment of cellulose not only greatly increased the mass fraction of cellulose dissolution (It has reached 15%) and retains the original crystal form and thermal stability of cellulose. The surface of the membrane was relatively dense, and the inside has regular microchannel . The factors affect the transparency and water flux of regenerated cellulose membranes were discussed by orthogonal experimental range analysis. The ability of the regenerated cellulose membrane to reject dyes was tested. The results showed that the rejection of methyl blue and congo red reached 100%, and the rejection rate of methyl orange reached 60%. The oil/water separation ability and the anti-pollution ability of the regenerated cellulose membrane were tested. The oil/water separation effect reached 100%. This membrane may have application prospect in water treatment, biotechnology.
研究领域:
材料科学
·
环境工程
·
膜技术
·
高分子化学
·
水处理
✓ 已验证
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2018
·
IF 5.091
Zanru Guo,Hongjian Gu,Qiang Chen,Zhanfeng He,Wenyuan Xu,Jiali Zhang,Yongxin Liu,Leyan Xiong,Longzhen Zheng,Yujun Feng
Hypothesis The effective separation and recovery of oils from water is important for the protections of ecosystems and the environment. Polymeric porous monoliths have been demonstrated as attractive absorbents for oil/water separation. However, the recyclability was mainly realized by squeezing, combustion, or centrifugation, which may restrict in elastic materials, destroy the adsorbates or need special apparatus. Thus it is desirable to developing monoliths with controllable oil absorption and desorption. Experiments A series of “smart” monoliths with pH-induced switchable wettability were fabricated by high internal phase emulsion (HIPE) polymerization and epoxide ring-opening for the incorporation of amine groups. The resultant monoliths and their wettabilities were examined using Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), nitrogen adsorption/desorption and contact angle analysis, respectively. The oil separation efficiency and recyclability were evaluated. Findings The monoliths with macroporous structure can undergo switchable wettability under reversible pH stimulation. As an absorbent, the monoliths not only separated and recovered organic solvents and oils (including crude oil) from aqueous mixtures through a reversible and recyclable absorption and desorption process upon alternating the pH between 7.0 and 1.0, but also continuously expulsed oils from water surfaces in a continuous manner with the aid of external driving pressures. Moreover, the monoliths also allowed the effective separation of surfactant-free and surfactant-stabilized oil-in-water emulsions with high separation efficiency.
研究领域:
环境科学
·
高分子材料
·
分离科学
·
界面化学
·
功能材料
✓ 已验证
DOI
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
·
2017
·
IF 6.065
Jianxian Zeng,Zhihui Dong,Zhe Zhang,Yuan Liu
A surface-grafted imprinted ceramic membrane (IIP-PVI/CM) for recognizing molybdate (Mo(VI)) anion was prepared by surface-initiated graft-polymerization. Firstly, raw alumina ceramic membrane (CM) was deposited with SiO 2 active layer by situ hydrolysis deposition method. Subsequently, γ-methacryloxy propyl trimethoxyl silane (MPS) was used as a coupling agent to introduce double bonds onto the SiO 2 layer (MPS-CM). Then, 1-vinylimidazole (VI) was employed as a functional monomer to graft-polymerization onto the MPS-CM (PVI-CM). During the graft-polymerization, the influence factors of grafting degree of PVI were investigated in detail. Under optimum conditions (monomer concentration 20 wt%, temperature 70 °C, initiator amount 1.1 wt% and reaction time 8 h), the grafting degree of 20.39 g/100 g was obtained. Further, Mo(VI) anion was used as a template to imprint in the PVI-CM by employing 1,6-dibromohexane as a cross-linking agent, and then Mo(VI) was removed, obtaining the IIP-PVI/CM with many imprinted cavities for Mo(VI). Thereafter, static adsorption and dynamic separation properties of IIP-PVI/CM for Mo(VI) were studied. Results indicate that IIP-PVI/CM shows a specific selectivity for Mo(VI) with the adsorption capacity of 0.69 mmol/100 g, and the selectivity coefficient of IIP-PVI/CM is 7.48 for molybdate to tungstate anions. During the dynamic separation, IIP-PVI/CM has also good selectivity for separation of Mo(VI) and W(VI) anions.
研究领域:
环境化学
·
材料科学
·
分离科学
·
高分子化学
·
无机分析化学
✓ 已验证
DOI
高影响因子
Desalination and Water Treatment
·
2024
·
IF 1
Chao Yang,Jun Yang,Ge Song,Limin Zang,Qifan Liu,Jianhui Qiu,Xue Yang,Chun Wang
Oil/water separation has recently attracted a great deal of attention for research due to the frequent occurrence of an oil spill as well as the increase of industrial and household oily wastewater. Therefore, the purpose of this study is to demonstrate underwater superoleophobic crosslinked phosphorylated poly(vinyl alcohol) hydrogel coated stainless steel mesh (CL-PPVA@SSM), which was fabricated using a simple dip-coating method and aldol reaction on the mesh substrate. The as-prepared CL-PPVA@SSM is capable of separating oil from a variety of different oil/water mixtures with high separation efficiency up to 99.2%, excellent recyclability and fast water permeate flux of 467.7 L m –2 h –1 , which makes it suitable for the separation of oil-water mixtures from oil-water emulsions. Also, in the oil-water separation process, the CL-PPVA@SSM is capable to remove organic dye from the water. The CL-PPVA@SSM exhibits stability under various harsh conditions such as mechanical abrasion. Importantly, the CL-PPVA@SSM shows a massive potential to separate kitchen waste oil/water mixtures due to the underwater superoleophobic property as required for the recycling of kitchen waste oil. Therefore, this method has been met with a promising application prospect of practical application.
研究领域:
材料科学
·
环境工程
·
高分子化学
·
表面工程
·
化学工程
·
纳米技术
·
水处理技术
✓ 已验证
DOI
高影响因子
Small
·
2024
·Vol. 20
·期 29
·2310092
·
IF 13
Yu-Ren Xue,Chang Liu,Hao-Cheng Yang,Hong-Qing Liang,Chao Zhang,Zhi-Kang Xu
Supported ionic liquid membranes (SILMs), owing to their capacities in harnessing physicochemical properties of ionic liquid for exceptional CO 2 solubility, have emerged as a promising platform for CO 2 extraction. Despite great achievements, existing SILMs suffer from poor structural and performance stability under high-pressure or long-term operations, significantly limiting their applications. Herein, a one-step and in situ interfacial polymerization strategy is proposed to elaborate a thin, mechanically-robust, and highly-permeable polyamide armor on the SILMs to effectively protect ionic liquid within porous supports, allowing for intensifying the overall stability of SILMs without compromising CO 2 separation performance. The armored SILMs have a profound increase of breakthrough pressure by 105% compared to conventional counterparts without armor, and display high and stable operating pressure exceeding that of most SILMs previously reported. It is further demonstrated that the armored SILMs exhibit ultrahigh ideal CO 2 /N 2 selectivity of about 200 and excellent CO 2 permeation of 78 barrers upon over 150 h operation, as opposed to the full failure of CO 2 separation performance within 36 h using conventional SILMs. The design concept of armor provides a flexible and additional dimension in developing high-performance and durable SILMs, pushing the practical application of ionic liquids in separation processes.
研究领域:
膜科学与技术
·
气体分离
·
环境化学
·
材料化学
·
化学工程
·
可持续能源技术
✓ 已验证
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2018
·
IF 3.927
Shufeng Li,Zhe Chen,Yinhua Yang,Zhihao Si,Pei Li,Peiyong Qin,Tianwei Tan
The hydrophobicity of porous particles is important for the performance of mixed-matrix membranes for pervaporation separation of n -butanol aqueous solution. Here, a strategy was proposed to further enhance the hydrophobicity of ZIF-8. ZIF-8 particles were first coated by polydopamine (PDA) to create chemically reactive surface and then modified with silane coupling agents n -propyltrimethoxysilane and n -octyltriethoxysilane. The water contact angles of the obtained P-ZIF-8@PDA and O-ZIF-8@PDA separately increased from 132.8° to 137.3° and 151.5°, which demonstrated a remarkable enhancement in hydrophobicity. The silane-modified ZIF-8 particles were subsequently incorporated into PDMS to fabricate mixed-matrix membranes, which exhibited an improved adsorption selectivity for butanol. The best membrane with 1 wt% loading (O-ZIF-8@PDA) exhibited a separation factor of 56 and butanol flux of 480.6 g m −2 h −1 for a 1.5 wt% butanol solution at 55 °C. The separation factor increased by 23% compared with that of a ZIF-8/PDMS membrane. Moreover, compared with those of a pure PDMS membrane, the separation factor and butanol flux increased by 34% and 85%, respectively. Thus, the strategy is an effective method to improve the PV performance of PDMS membranes for butanol separation.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
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
Science China-Materials
·
2021
·Vol. 65
·期 5
·1285-1293
·
IF 8.273
Zheng Mang,Li Qi,Liu Mingyang,Liu Jianan,Zhao Chen,Xiao Xudong,Wang Hongli,Zhou Jing,Zhang Liping,Jiang Baojiang
As an n-type semiconductor, In 2 O 3 is considered a promising photocatalyst for producing amino acids using biomass derivatives as precursors. However, similar to other intrinsic semiconductors, In 2 O 3 suffers from poor charge dynamics. Herein, we show the synthesis of Mo-doped In 2 O 3 (Mo-In 2 O 3 ) with a porous rod-shaped structure through a one-step solvothermal reaction followed by calcination. Under visible-light irradiation, Mo-In 2 O 3 achieves a high conversion rate of 81% for the reaction that transforms lactic acid into alanine with a selectivity of 91%. Spectroscopic techniques and density functional theory calculations reveal that Mo doping introduces defect states slightly below the conduction band of In 2 O 3 , which improves the separation of photogenerated electron-hole pairs. In addition, Mo atoms on the surface form extra adsorption and reaction centers that greatly enhance the reaction rate. This work provides insights into the development of transition metal-doped semiconductor photocatalysts to produce amino acids.
研究领域:
材料科学
·
光催化
·
半导体材料
·
生物基化学品
·
分子催化
·
纳米材料
✓ 已验证
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2021
·
IF 4.539
Cheng Liu,Xinyue Zhang,Yunfei Zheng,Zijie Ren,Weng Fu,Siyuan Yang
Fluorite is easily affected by the slime coating of fine barite during the froth flotation separation. In this work, the water glass (WG) was utilized as a dispersant to improve the flotation separation performance between fluorite and barite slimes. The single minerals flotation results revealed that barite slimes could be selectively depressed by gelatinized starch (GS), while WG had little effect on the floatability of barite and fluorite using sodium oleate (NaOl) as a collector. The flotation results of artificially mixed minerals showed that the separation efficiency of fluorite from barite was significantly reduced when barite existed as slimes. However, the presence of WG could eliminate the negative effect of barite slimes on the flotation fluorite by using the reagents scheme of GS/NaOl. Zeta potential results indicated that the fluorite surface charge turned from positive to negative with the addition of WG, then the barite slimes coating was detached from the fluorite surface because of the electrostatic repulsion, allowing the cleaning fluorite surface to once again interact with NaOl. The DLVO calculation was also conducted to reveal the agglomerate and disperse of different particles in the flotation system of fluorite-barite slimes.
研究领域:
矿物加工工程
·
浮选化学
·
胶体与界面科学
·
资源综合利用
·
无机非金属材料
✓ 已验证
DOI
高影响因子
ENVIRONMENTAL POLLUTION
·
2018
·
IF 4.358
Zhaocheng Zhang,Dongyang He,Haiyang Liu,Miao Ren,Yanan Zhang,Jiao Qu,Nan Lu,Jiunian Guan,Xing Yuan
Black phosphorus (BP), a superior two-dimensional (2D) semiconductor, has attracted much attention due to its unique properties. The graphene (GR)-BP hybrid was synthesized through one pot chemical vapor transport (CVT) approach. The characterization results indicated that P atom was successfully incorporated into GR by the formation of P-C bond. Remarkably, the newly-synthesized GR-BP represented high photocatalytic activity towards 2-chlorophenol (2-CP) degradation, due to the high efficiency of charge separation and transformation caused by the direct band gap of BP and carrier mobility of GR. The removal efficiency for 2-CP reached up to 87.08% within visible light irradiation for 180 min ( λ > 420 nm). The degradation rate of GR-BP hybrid for 2-CP was approximately 7.29-fold than that of BP within 30 min. In addition, the little increasing of the peak for P-O bond in GR-BP hybrid was observed after being exposed in air for 15 days, meant that the stability of BP was significantly enhanced. It was caused by the decreasing of the oxidation sites in BP due to the formation of P-C bond in hybrid. In brief, our synthetic method for GR-BP not only provides a novel route for the improvement of the stability of BP, but also constitutes an insight into the promising practical application of BP in the photocatalysis field.
研究领域:
材料科学
·
纳米科技
·
光催化
·
半导体材料
·
环境化学
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2019
·
IF 5.155
Xingchao Zhang,Ruoyu Zhang,Siying Niu,Jiming Zheng,Chongfeng Guo
The MoS 2 /g-C 3 N 4 heterojunction composite (marked as MoS 2 /g-C 3 N 4 -H) was successfully prepared via calcining the melamine coated MoS 2 nano-sphere, where the thin g-C 3 N 4 nano-sheets were tightly grown on the surface of MoS 2 nano-sphere to form MoS 2 inlaying in g-C 3 N 4 heterostructure. The detailed charge transfer mechanism was discussed by combining theoretical calculation and experiments, in which the intrinsic cause of photo-generated charge separation and transfer was determined as the directional built-in electric field driven by different Fermi levels of MoS 2 and g-C 3 N 4 . Comparatively, the enhanced photo-catalytic performance and stability of the sample were assessed by degrading the Rhodamine (RhB) and reducing the Dichromate (Cr 6+ ) solutions under the irradiation of the simulated sunlight, which could be attributed to the widened spectral absorption range and improved electron-hole separation rate. Based on above results, the photo-catalytic mechanism involving redox reactions was also clearly proposed.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）