Desalination and Water Treatment
·
2024
·
IF 1
Xu Zhang,Fan Yang,Jialing Qin,Huanghu Peng,Zezhou Chen,Lei Che,Shouxin Zhu,Wei Yang
The heterogeneous catalyst of CeO 2 /ZSM5 was applied to hydrolyze Congo red in subcritical water for the first time in the present study. The hydrolysis rate of Congo red could be significantly accelerated by introducing only 5 mg of 5% CeO 2 /ZSM5. The Congo red could be completely hydrolyzed at 220°C for 2 min—a reaction temperature 40°C lower than in the absence of 5% CeO 2 /ZSM5. In addition, the 5% CeO 2 /ZSM5 could be recycled for another run, and its Congo red hydrolysis efficiency and surface morphology showed no obvious change after 3 runs of recycling. The hydrolysis kinetics of Congo red in subcritical water could be well expressed by the Weibull model. The activation energy for hydrolysis of Congo red in subcritical water in the presence of 5% CeO 2 /ZSM5 (104.8 kJ mol –1 ) was much lower than in the absence of 5% CeO 2 /ZSM5 (155.9 kJ mol –1 ). The frequency factors were calculated to be 8.1 × 10 9 and 1.9 × 10 14 min –1 in the presence and absence of 5% CeO 2 /ZSM5, respectively. With these excellent properties, 5% CeO 2 /ZSM5 may prove to be an advantageous catalyst for the hydrolysis of Congo red in textile wastewater, in subcritical water.
研究领域:
环境化学
·
催化化学
·
水处理技术
·
绿色化学
·
反应动力学
✓ 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
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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
POLYMER
·
2018
·
IF 3.483
Dongxue Yang,Lingfeng Li,Binling Chen,Shuxian Shi,Jun Nie,Guiping Ma
In order to improve the removal ability of chitosan (CS) to heavy metal ions , in this study, rich amino-functionalized CS electrospun membranes have been prepared. During the efficient synthesis, poly (glycidyl methacrylate) (PGMA) and polyethylenimine (PEI) were sequentially grafted on the surface of CS electrospun membrane. The success of introduction of amino-group on the CS were confirmed by X-ray diffractometer (XRD), attenuated total reflection-fourier transform infrared (ATR-FTIR), and X-ray photoelectron spectroscopy (XPS). The ability of remove heavy metal ions (Cr(VI), Cu(II) and Co(II)) of the as-prepared membrane (CS-PGMA-PEI) was investigated. The adsorption equilibrium of the heavy metal ion solutions was rapidly established in 60 min. Adsorption kinetics analysis reveals that the adsorption process of CS-PGMA-PEI electrospun membrane was dominated by a Pseudo-second-order model. Its adsorption isotherm can be described by the Langmuir model. The maximum adsorption capacities calculated by Langmuir model were 138.96, 69.27 and 68.31 mg g −1 for Cr(VI), Cu(II) and Co(II), respectively. The adsorption ability of CS-PGMA-PEI electrospun membrane toward metal ions was found in an order of Cr(VI) > Cu(II) > Co(II). CS-PGMA-PEI membrane also exhibited a good reproducibility and stability. Our study may provide a way to synthesize membranes for water purification .
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
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
COMBUSTION AND FLAME
·
2024
·
IF 5.8
Hong Wang,Bingzhi Liu,Qiang Xu,Shijun Dong,Zhandong Wang,Long Zhu
Cyclopentanone (CPN) is a widely available biofuel with excellent combustion properties, but detailed speciation profiles during its pyrolysis have rarely been studied. This work examines the pyrolysis of CPN in a jet-stirred reactor (JSR) at atmospheric pressure, with residence time of 2 s and a temperature range from 830 K to 1100 K. Dozens of pyrolysis intermediates and products were measured using synchrotron vacuum ultraviolet photoionization mass spectrometry (SVUV-PIMS) and gas chromatography (GC). Among them, several new species were observed, including water, carbon dioxide , formaldehyde, indene , 1,2-dihydroindene, naphthalene , 1,2-dihydronaphthalene, 1-methylnaphthalene, acenaphthylene , biphenyl , and fluorene . A detailed kinetic model was developed based on the literature, and in general, it predicted the experimental results for most species well. Kinetic analyses indicated that the consumption of CPN was controlled by the bimolecular reactions with H atom. The formation of water, carbon dioxide and formaldehyde could be explained by the reaction pathways of OH radical. The pyrolysis of CPN yielded a significant number of alkenes and alkynes at higher temperatures; the bimolecular addition reactions of these species with resonantly stabilized radicals are important to the formation of polycyclic aromatic hydrocarbons (PAHs). Based on those, this work provides valuable insights into CPN pyrolysis chemistry and it promotes the development of a comprehensive CPN combustion model.
研究领域:
燃烧化学
·
能源化学
·
反应动力学
·
分析化学
·
环境化学
✓ 已验证
DOI
高影响因子
BIORESOURCE TECHNOLOGY
·
2020
·
IF 7.539
Kaijun Wang,Sining Yun,Tian Xing,Bingjie Li,Yasir Abbas,Xinming Liu
The effects of binary and ternary trace elements (TEs) (Fe/Co, Fe/Ni, and Fe/Co/Ni) on the anaerobic digestion (AD) of cattle manure were investigated using kinetic models (first-order, logistic, modified Gompertz, and Coats-Redfern) and experimental measurements. Binary and ternary TEs can significantly improve the biogas production rate and yield potential. The deviation between the predicted and measured data for biogas yield with logistic model (2.1%–5.3%) and modified Gompertz model (0.32%–2.9%) was smaller than that with first-order kinetic model (6.9%–9.9%). The Coats-Redfern model fitting indicated that the activation energy of digestates with trace elements during pyrolysis was reduced by 3.9%–26.2% compared with the control group. Meanwhile, digestates with TEs showed remarkable fertility (5.72%–5.95%). The combination of kinetic models and experimental measurements can effectively quantify the effect of TEs on AD performance and provide an informed choice for industrial production.
研究领域:
环境科学
·
农业工程
·
生物质能源
·
废物资源化
·
生物化学工程
✓ 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
PROCEEDINGS OF THE COMBUSTION INSTITUTE
·
2022
·Vol. 39
·期 1
·315-324
·
IF 6.535
Qianjin Lin,Wanxiong Liao,Jia Cheng,Chun Zou,Bin Yang,Wenxiang Xia
Few studies on the low-temperature combustion behavior of MIPK, being a promising fuel additive , have been conducted. In this work, ignition delay times (IDTs) of MIPK were measured in the temperatures ranging between 780–910 K and pressures of 20 and 25 bar using a rapid compression machine (RCM). Oxy-fuel combustion combined with biofuel could remove CO 2 from the atmosphere. The IDTs of MIPK were measured in the temperatures ranging between 1125–1600 K under the O 2 /CO 2 atmosphere at the pressures of 1 and 10 bar using a shock tube . A low to high-temperature MIPK kinetic model (HUST-MIPK model) was proposed, in which the low-temperature sub-model consists of 19 low-temperature reaction classes and was constructed by analogy-based method, the high-temperature sub-model was adapted from the works of Cheng et al.. The predictions of HUST-MIPK model are in good agreement with the present low-temperature IDTs, high-temperature O 2 /CO 2 atmosphere IDTs, and the literature experimental data. The negative temperature coefficient (NTC) behavior was not observed in the temperature range from 790 to 910 K in the present RCM experiments, but was observed for methyl propyl ketone (MPK) and diethyl ketone (DEK) under similar conditions. The low-temperature chemistry of three pentanone isomers (MIPK, MPK, and DEK) was compared using the flux and sensitivity analysis. The comparison of the experimental high-temperature IDTs between O 2 /CO 2 and O 2 /Ar atmospheres indicates the IDTs of MIPK under O 2 /CO 2 atmosphere are longer than those under O 2 /Ar atmosphere at 1 bar, and the effects of CO 2 are almost independent of the pressure. The physical and chemical effects of CO 2 on the ignition were studied in detail.
研究领域:
燃烧化学
·
燃料化学
·
反应动力学
·
能源工程
·
大气环境影响
✓ 已验证
DOI
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
·
2019
·
IF 4.561
Pan Zhang,Lemeng Wang,Chunjie Lu,Mengying Li,Shujun Yu,Dong Fu
The surface tensions of 2‑diethylaminoethanol (DEAE)‑ N ‑(2‑aminoethyl)ethanolamine (AEEA), DEAE‑ N ‑methyl‑1,3‑propane‑diamine (MAPA) and DEAE‑1,4‑butanediamine (BDA) aqueous solutions have been measured by using the BZY-1 surface tension meter. The mass fractions of DEAE and AEEA/MAPA/BDA respectively ranged from 0.300 to 0.500 and 0.050 to 0.150. The temperature ranged from 303.2 K to 323.2 K. A thermodynamic equation was proposed to model the surface tension and the calculated results agreed well with the experiments. The effects of temperature and mass fraction of amines on the surface tension were demonstrated on the basis of experiments and calculations. The surface thermodynamics including surface enthalpy and surface entropy of blended amine aqueous solutions were also determined, and their temperature and mass fraction dependences were analyzed.
研究领域:
物理化学
·
溶液化学
·
热力学
·
表面科学
·
化工材料
✓ 已验证
DOI
高影响因子
JOURNAL OF CHEMICAL THERMODYNAMICS
·
2017
·
IF 2.726
Tianhua Huang,Dingqiang Lu,Xiuquan Ling,Xinxian Wang,Tongqi Liu,Fangfang Shen,Kefei He
In this paper, we focused on solubility and solution thermodynamics of istradefylline. Herein, we investigated the solubility and solution thermodynamics of istradefylline in binary solvent mixtures by gravimetric method. The solubility of istradefylline in (ethyl acetate + isopropanol), (ethyl acetate + tetrahydrofuran) and (ethyl acetate + acetone) was measured in the temperature range of 278.15 K–333.15 K under atmospheric pressure. In order to correlate the solubility of istradefylline, we employed the modified Apelblat equation, general cosolvency model and Jouyban-Acree model. Computational results showed that the modified Apelblat equation and general cosolvency model have low mean deviation. As calculated by van’t Hoff equation, the values of thermodynamic properties such as Gibbs energy, enthalpy, and entropy proved that the dissolution process is endothermic.
研究领域:
药物化学
·
药剂学
·
物理化学
·
药物热力学
·
分子溶解行为
·
药物结晶
✓ 已验证
DOI
高影响因子
International Journal of Applied Linguistics
·
2003
·Vol. 13
·期 1
·1-22
·
IF 0
Sandra Lee McKay
This article argues that the teaching of English as an international language (EIL) should be based on an entirely different set of assumptions than has typically informed English language teaching (ELT) pedagogy. To begin, several defining features of an international language are described. Because these features have altered the nature of English itself, the author maintains that the pedagogy for teaching English must also change. The author then describes how two developments – a dramatic increase in the number of second language speakers of English and a shift in the cultural basis of English – have significantly altered the nature of English. These changes challenge several common assumptions of ELT pedagogy, namely that: interest in learning of English is largely the result of linguistic imperialism; ELT research and pedagogy should be informed by native speaker models; the cultural content for ELT should be derived from the cultures of native English speakers; the culture of learning that informs communicative language teaching (CLT) provides the most productive method for ELT. The article ends by positing major assumptions that should inform a comprehensive theory of EIL pedagogy.
研究领域:
应用语言学
·
语言教育
·
跨文化交际
·
第二语言习得
·
教育语言学
✓ 已验证
DOI
COMBUSTION AND FLAME
·
2021
·
IF 4.185
Zhi-Hao Jin,Jin-Tao Chen,Wang Li,Shu-Bao Song,Jiu-Zhong Yang,Zhen-Yu Tian
Owing to significant advantages over traditional biofuels, 2-methylfuran (MF) has arisen extensive interest as next generation biofuels . Atmospheric pressure pyrolysis of a 1:1 blend of MF with a three-component (3C) surrogate jet fuel was conducted in a flow tube using synchrotronphotoionization and molecular beam mass spectrometry techniques within a temperature range of 898–1223 K. Therein, the 3C surrogate fuel consists of 66.2% n-dodecane (NC 12 H 26 ), 18.0% 1,3,5-trimethylcyclohexane (T135MCH) and 15.8% n-propylbenzene (NPB, A1C 3 H 7 ). The detailed kinetic model including 579 species and 3474 reactions was developed via validating against both measured and literature data with reasonable agreement. MF exhibits no obvious influence on the 3C components pyrolysis . However, 3C mixtures play an important roles in MF decomposition: lower initial temperature and different decomposition pathways. In the meantime, n-propylbenzene (NPB) pyrolysis curve in 3C and 3C+MF significantly transfers to low temperature zone after 1000 K in contrast to pure NPB, while smaller change was found in the decomposition curve of n-dodecane. Compared with 3C pyrolysis, 3C+MF blends have less formation of aromatic species and light hydrocarbons except for vinylacetylene (C 4 H 4 ) and acetylene (C 2 H 2 ). Allyl radical (C 3 H 3 ) has significant roles in benzene ring formation. The combination of allyl radical with propargyl radical producing benzene and H radical (aC 3 H 5 + C 3 H 3 = A1 + 2H) has the highest contribution to the benzene formation in both 3C and 3C+MF. Moreover, most of naphthalene (A2) formation is also related to C 3 H 3 radical via reaction: A1CH 2 + C 3 H 3 = A2 + H, rather than via HACA (hydrogen abstraction carbon addition) reaction. Interaction of fuel blends was mainly presented through the common and important sensitive reactions which are much to do with CH 3 and H radicals. The overview of product distribution was investigated by providing comparisons of carbon conversion rates during the pyrolysis of 3C and 3C+MF. These results will be helpful to better understand the pyrolysis properties of MF/jet fuel surrogate blends and could contribute to developing new generation biofuels for aviation.
研究领域:
燃料化学
·
燃烧动力学
·
生物燃料
·
能源化学
·
反应机理
·
质谱分析
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）