International Journal of Minerals Metallurgy and Materials
·
2019
·Vol. 26
·期 12
·1512-1522
·
IF 1.221
Zhao Jun,Zuo Hai-bin,Wang Jing-song,Xue Qing-guo
The high-value utilization of low-rank coal would allow for expanding energy sources, improving energy efficiencies, and alleviating environmental issues. In order to use low-rank coal effectively, the hypercoals (HPCs) were co-extracted from two types of low-rank coal and biomass via N-methyl-2-purrolidinone (NMP) under mild conditions. The structures of the HPCs and residues were characterized by proximate and ultimate analysis, Raman spectra, and Fourier transform infrared (FT-IR) spectra. The carbon structure changes within the raw coals and HPCs were discussed. The individual thermal dissolution of Xibu (XB) coal, Guandi (GD) coal, and the biomass demonstrated that the biomass provided the lowest thermal dissolution yield Y 1 and the highest thermal soluble yield Y 2 at 280°C, and the ash content of three HPCs decreased as the extraction temperature rose. Co-thermal extractions in NMP at various coal/biomass mass ratios were performed, demonstrating a positive synergic effect for Y 2 in the whole coal/biomass mass ratios. The maximum value of Y 2 was 52.25wt% for XB coal obtained with a XB coal/biomass of 50wt% biomass. The maximum value of Y 2 was 50.77wt% for GD coal obtained with a GD coal/biomass of 1:4. The difference for the optimal coal/biomass mass ratios between XB and GD coals could be attributed to the different co-extraction mechanisms for this two type coals.
研究领域:
能源化学
·
煤化工
·
生物质转化
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热化学转化
·
资源综合利用
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DOI
高影响因子
FLUID PHASE EQUILIBRIA
·
2021
·
IF 2.775
Zhendong Wang,Shuo Chen,Bingxiao Feng,Hongbing Song,Meng Xiao,Hengjun Gai,Tingting Huang
Extracting phenol from coal tar has great economic significance. In this paper, a process for separating phenol from coal tar using mono-ethanolamine (MEA) as extractant was proposed, the conceptual design and optimized of the process was carried out by using Aspen Plus software. To ensure the accuracy of simulation, the vapor-liquid equilibrium data of MEA + phenol binary system were measured under different pressures. The binary interaction parameters of NRTL model, Wilson model and UNIQUAC model were fitted with the experimental data by data regression system. The results show that the deviation of NRTL model is less than that of Wilson model and UNIQUAC model. Considering that the boiling point difference between MEA and phenol is only 10°, two energy-saving schemes of double effect distillation are introduced into the conceptual process proposed in this paper, which can save 20% and 44.8% respectively compared with the traditional single tower distillation process . This paper provides reference for the industrial application of MEA in the extraction of phenol from coal tar.
研究领域:
化学工程
·
分离科学
·
热力学
·
能源化工
·
工业催化
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DOI
高影响因子
MICROCHEMICAL JOURNAL
·
2014
·
IF 3.583
Shengling Sun,Jie Li
A method has been developed for the determination of zirconium (Zr), hafnium (Hf), niobium (Nb), tantalum (Ta), molybdenum (Mo), tungsten (W), and tin (Sn) in seawater by quadrupole inductively coupled plasma-mass spectrometry (Q-ICP-MS). The method is based on separation of the seven elements by extraction chromatography using N-benzoyl-N-phenylhydroxylamine (BPHA) supported on a microporous acrylic ester polymeric resin. The optimized procedure indicates that the BPHA resin has high selective adsorption for Zr, Nb, Mo, Sn, Hf, Ta, and W (known as fluoride soluble elements), whereas other interference and matrix elements are minimally adsorbed. The optimized eluent mixture with their molarity gives satisfactory recoveries for all analytes. The recovery can be achieved 99% for Zr, 97% for Nb, 97% for Mo, 99% for Sn, 99% for Hf, 95% for Ta, and 98% for W, respectively, by eluting with 6 mL of 6 mol L − 1 HF/1 mol L − 1 HCl. Furthermore, the technique for separation and enrichment of these elements provides a low total method blank. The detection limits for this method are 0.5 ppt for Zr, 0.2 ppt for Nb, 1.7 ppt for Mo, 1.0 ppt for Sn, 0.1 ppt for Hf, 0.1 ppt for Ta, and 0.3 ppt for W, respectively. The validity of the method is evaluated by replicate analyses of seawater reference materials; the precision of the results is better than 3% (RSD, n = 4), and the results are in good agreement with certified values. The established procedure has proved to be both practical and effective for seawater sample analyses.
研究领域:
分析化学
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海洋化学
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环境地球化学
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痕量元素检测
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质谱分析
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DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2018
·
IF 6.735
Tingliang Xie,Minxuan Chen,Cong Xu,Jing Chen
Microextractors are known to provide high mass transfer rates for the extraction and separation of rare-earth elements (REEs). High-throughput microextractors are essential for industrial-scale production of REEs, but few practical studies have been conducted to date. In this work, a chaotic advection microextractor, i.e., a three-stage microextractor, was designed and demonstrated to extract Pr(III) and Ce(III) efficiently from nitric acid media at high throughputs by using 2-ethylhexyl phosphoric acid-2-ethylhexyl ester (P507) and sulfonated kerosene as an extraction agent and a diluent, respectively. Flow visualization experiments showed that the dispersed phase could be effectively broken into small droplets owing to vortex and recirculation flows. Microextraction experiments performed under optimal extraction conditions indicated that at low throughputs, the concentration ratio D , extraction efficiency E , and separation factor β decreased with an increase in the throughput, whereas at high throughputs, D , E , and β increased with an increase in the throughput. An extraction efficiency close to that of co-current balanced extraction was successfully achieved, even at a high total throughput of 100 mL/min and a rather short residence time of 0.029 s. Thus, the chaotic advection microextractor features a high throughput and high extraction efficiency, which are appropriate for the high-efficiency extraction and separation of REEs.
研究领域:
化学工程
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分离科学
·
稀土冶金
·
微流控技术
·
过程强化
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DOI
高影响因子
JOURNAL OF PHARMACEUTICAL AND BIOMEDICAL ANALYSIS
·
2018
·
IF 2.831
Xiaoping Liang,Ping Hu,Hongyang Zhang,Wen Tan
In this work, hypercrosslinked strong anion-exchange polymer resins (HXLPP-SAX) were synthesized and evaluated as solid-phase extraction (SPE) sorbents for extracting fluoroquinolones (FQs) in milk samples. These particles were prepared using a protocol that was facile and cost-effective by combining hypercrosslinking reactions and quaternisation reactions in one step. After the synthesis, the morphological properties and anion-exchange, adsorption, and selectivity performances of the HXLPP-SAX resins were characterized and evaluated. It was shown that the polymers were monodisperse microspheres, with the mean diameters of 2–4 μm, ion-exchange capacity (IEC) of 0.311 meq/g, and specific surface area more than 1000 m 2 /g. The resins applied as SPE sorbents possessed high selectivity in the extraction of amphoteric compounds (enoxacin and enrofloxacin as the representatives) followed by HPLC-UV analysis, as compared to commercially available strong anion-exchange sorbents (Oasis MAX). The SPE-HPLC-UV method was fully validated and exhibited good linearity (10–2000 ng/g, R 2 ≥ 0.997), low limits of detection (2.8–5.1 ng/g), good recoveries (85.8%–117.9%, RSDs ≤ 7.1%) and precisions (intra-day RSDs ≤ 7.7% and inter-day RSDs ≤ 9.4%). Then the method was performed the selective enrichment of six FQs (enoxacin, norfloxacin, ciprofloxacin, lomefloxacin, enrofloxacin, and sparfloxacin) in milk samples. The present results demonstrated that the proposed resins exhibited a promising potential for the enrichment and determination of FQ residues in milk samples as well as in other samples with complex matrices.
研究领域:
分析化学
·
食品科学
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产品关联
DOI
PubMed
高影响因子
ANALYTICA CHIMICA ACTA
·
2019
·
IF 5.256
Xiaoxiao Wei,Yuzhi Wang,Jing Chen,Panli Xu,Wei Xu,Rui Ni,Jiaojiao Meng,Yigang Zhou
Novel polymeric deep eutectic solvents (PDES) based on 3-acrylamidopropyl trimethylammonium chloride/D-sorbitol functionalized amino-magnetic (Fe 3 O 4 NH 2 ) metal-organic framework (HKUST-1-MOF) composites (Fe 3 O 4 NH 2 @HKUST-1@PDES) were synthesized and characterized by field emission transmission electron microscope (FE-SEM), transmission electron microscope (TEM), X-ray diffraction (XRD), fourier transform infrared spectrometry (FT-IR), thermal gravimetric analysis (TGA), vibrating sample magnetometer (VSM) and zeta potentials . Then the composites were firstly utilized to selectively separate malachite green (MG) and crystal violet (CV) coupled with magnetic solid-phase extraction (MSPE). A response surface methodology (RSM) based on Latin hypercube sampling (LHS) was selected to analytically optimize the extraction parameters including initial concentration of dyes, extraction time, pH value and extraction temperature. The maximum extraction amount and optimal extraction conditions predicted by the RSM model matched well with the actual experimental results, and the extraction amount was 966.93 mg g −1 for MG and 788.90 mg g −1 for CV,respectively. The results indicated that the model possessed higher calculation accuracy through analyzing fewer sample points, thereby achieving theoretical prediction of extraction amount and conditions and being a prefect supplementary to actual experiments. The electrostatic interaction between the composites and cationic dyes played the main roll in the extraction process. The proposed extraction method exhibited lower limit of detection (98.19 ng mL −1 for MG and 23.97 ng mL −1 for CV) and preeminent precision (RSD ˂ 0.4%). Spiked recoveries of fish samples at three spiking levers ranged from 89.43% to 100.65% for MG and 95.29%–98.03% for CV. All results highlighted the excellent potential of Fe 3 O 4 NH 2 @HKUST-1@PDES-MSPE strategy in selective separation of cationic dyes in complex medium.
研究领域:
分析化学
·
材料科学
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产品关联
DOI
PubMed
高影响因子
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
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DOI
高影响因子
RSC Advances
·
2014
·Vol. 4
·期 90
·49153-49160
·
IF 3.708
Dan Liu,Nan Song,Ye-Chun Cheng,Dai-Xiong Chen,Qiong Jia,Ying-Wei Yang
Poly(glycidyl methacrylate-co-ethylene dimethacrylate) modified with a new supramolecular macrocycle, carboxylatopillar[5]arene, was successfully prepared inside a capillary. The functionalized polymer monolith material was characterized by scanning electron microscopy, X-ray photoelectron spectroscopy, thermogravimetric analysis, and Fourier-transformed infrared spectra. The experimental results showed that this type of polymer possess a good network skeleton structure and excellent extraction properties for the enrichment of parabens by polymer monolith solid-phase microextraction coupled with high performance liquid chromatography. Compared with other pre-treatment methods, the simple operation and inexpensive instrumentation characteristics of the developed polymer monolith SPME method make it more suitable for the extraction of parabens in red wine samples with great potential for further broadening its applications in the enrichment of other real samples.
研究领域:
分析化学
·
环境科学
·
食品安全
·
材料科学
·
色谱学
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DOI
高影响因子
CHINESE JOURNAL OF CHEMISTRY
·
2011
·Vol. 29
·期 4
·778-782
·
IF 0.773
Haining Shi,Zonghua Wang,Hui Wang,Rui Zhao,Mingyu Ding
An anion-exchange chromatography method combined solid phase extraction (SPE) was developed for the simultaneous analysis of glycolate acid (GL), monochloroacetic acid (MCA) and dichloroacetic acid (DCA) in synthetical betaine products. The analytes and unknown anionic impurities were well separated on a Metrosep A supp5 anion-exchange column (150 mm×4 mm) with 2.0 mmol/L Na 2 CO 3 +2.0 mmol/L NaHCO 3 solution as eluent. Suppressed conductivity detection was used. A strong cation exchange (SCX) solid phase extraction (SPE) cartridge was used to reduce the concentration of matrix betaine and a Cleanert IC-Ag pretreatment cartridge was used to remove high Cl − concentration. The detection limits of GL, MCA and DCA were 0.09, 0.017 and 0.05 µg/L, respectively. The relative standard deviations (RSDs) of the retention times and peak areas were less than 0.09% and 0.49%, respectively. The recoveries of the three analytes were between 90.6% and 100.8%. The analytical results showed that GL and DCA were present in high concentration and no MCA was found when the proposed ion chromatography method was applied to three synthetical betaine samples. The proposed method is simple, sensitive and timesaving, and is also suitable for routine analysis in quality control of synthetical betaine products.
研究领域:
分析化学
·
药物质量控制
·
分离科学
·
环境分析
·
食品化学
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DOI
高影响因子
TheScientificWorldJOURNAL
·
2014
·Vol. 2014
·期 1
·162465
·
IF 1.219
Haiying Luo,Yanping Xian,Xindong Guo,Donghui Luo,Yuluan Wu,Yujing Lu,Bao Yang
A new technique was established to identify eight organophosphate esters (OPEs) in this work. It utilised dispersive liquid-liquid microextraction in combination with ultrahigh performance liquid chromatography/tandem mass spectrometry. The type and volume of extraction solvents, dispersion agent, and amount of NaCl were optimized. The target analytes were detected in the range of 1.0–200 µ g/L with correlation coefficients ranging from 0.9982 to 0.9998, and the detection limits of the analytes were ranged from 0.02 to 0.07 µ g/L ( S / N = 3). The feasibility of this method was demonstrated by identifying OPEs in aqueous samples that exhibited spiked recoveries, which ranged between 48.7% and 58.3% for triethyl phosphate (TEP) as well as between 85.9% and 113% for the other OPEs. The precision was ranged from 3.2% to 9.3% ( n = 6), and the interprecision was ranged from 2.6% to 12.3% ( n = 5). Only 2 of the 12 selected samples were tested to be positive for OPEs, and the total concentrations of OPEs in them were 1.1 and 1.6 µ g/L, respectively. This method was confirmed to be simple, fast, and accurate for identifying OPEs in aqueous samples.
研究领域:
环境分析化学
·
污染生态学
·
毒物代谢
·
水质安全
·
持久性有机污染物
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DOI
高影响因子
JOURNAL OF PHARMACEUTICAL AND BIOMEDICAL ANALYSIS
·
2010
·Vol. 52
·期 4
·615-619
·
IF 2.453
Shenguang Ge,Mei Yan,Xiaoliang Cheng,Congcong Zhang,Jinghua Yu,Peini Zhao,Weiqiang Gao
A simple and convenient on-line molecular imprinted solid-phase extraction flow-injection fluorescence sensor was developed in this study. Florfenicol (FF)-imprinted polymer was prepared by self-assembly with acrylamide (AM) as functional monomer and ethylene glycol dimethacrylate (EGDMA) as cross-linker. The binding characteristics of the imprinted polymer to florfenicol were evaluated by equilibrium binding experiments, and the morphology of the imprinted polymer was studied by scanning electron microscope (SEM). Fluorescence intensity of 3-p-nitrylphenyl-5-(2′-sulfonophenylazo) rhodanine (4NRASP) and bovine serum albumin (BSA) was inhibited by FF. Under optimum conditions the intensity of fluorescence shows a linear relationship with the concentration of FF over the range of 1.2 × 10 −6 to 2.6 × 10 −5 g mL −1 with a regression equation of Δ I = 23.54 + 17.86 c ( c 10 −6 g mL −1 ) ( r = 0.9965, n = 6). The low detection limit of FF was found to be 3.4 × 10 −7 g mL −1 according to 11 parallel determinations for the blank solution. The relative standard deviation for the determination of 2.0 × 10 −6 g mL −1 FF solution was 3.5% ( n = 11). This proposed sensor could be satisfactorily applied to the determination of FF in liver and meat samples.
研究领域:
分析化学
·
药物残留检测
·
食品安全
·
分子识别
·
环境监测
·
兽药代谢
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DOI
高影响因子
MARINE POLLUTION BULLETIN
·
2015
·Vol. 102
·期 1
·142-147
·
IF 2.991
Xiuping He,Xiaoqi Mei,Jiangtao Wang,Ziru Lian,Liju Tan,Wei Wu
An effective and highly selective molecularly imprinted material was prepared by suspension polymerization for the isolation and pre-concentration of synthetic estrogen diethylstilbestrol (DES) in seawater . The obtained MIPMs were proved to have more uniform size and porous structure, with maximum adsorption capacity of 8.43 mg g − 1 almost two times more than NIPMs (4.43 mg g − 1 ). The MIPMs showed no significant deterioration of the adsorption capacity after five rounds of regeneration. An off-line molecularly imprinted solid phase extraction (MISPE) method followed by HPLC–DAD was proposed for the detection of DES in seawater , and recoveries were satisfactorily higher than 77%. Four seawater samples in aquaculture area were analyzed and 0.61 ng mL − 1 DES was detected in one sample. The result demonstrated that this method can be used for the rapid separation and clean up of trace residual of DES in seawater.
研究领域:
环境分析化学
·
海洋环境污染
·
分子印迹技术
·
药物残留检测
·
水体污染物
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）