Search | Engineering

订阅投稿

首页工程期刊工程焦点工程成就工程前沿关于我们 English

资源类型

期刊论文 271

年份

2023 28

2022 26

2021 23

2020 20

2019 14

2018 9

2017 14

2016 11

2015 14

2014 22

2013 20

2012 11

2011 11

2010 6

2009 15

2008 11

2007 10

2004 1

2003 1

2001 2

展开︾

关键词

吸附 11

动力学 6

热力学 2

&alpha 1

185 nmUV 1

CMAC神经网络 1

MOF基催化剂 1

PP 1

Pd局域环境 1

WPC 1

乙炔半加氢 1

二苯甲酮 1

亚麻屑纤维素 1

产氧反应 1

偶氮苯 1

六自由度并联平台 1

内球配位 1

再生 1

分子开关 1

展开︾

检索范围：

排序：展示方式：

Kinetics and thermodynamics of the phosphine adsorption on the modified activated carbon

Bingnan REN

《化学科学与工程前沿（英文）》 2011年第5卷第2期页码 203-208 doi: 10.1007/s11705-010-0571-0

摘要： The kinetics and the thermodynamics of phosphine (PH ) adsorption on the modified activated carbon have been explained for the adsorption process of PH . This study investigated the kinetic and thermodynamic properties of PH adsorption on the activated carbon impregnated with 5% HCl solution. The thermodynamic properties including PH adsorption isotherm and adsorption heat were separately investigated at 20°C, 70°C, 90°C. The results showed that the Freundlich-type isotherm equation described the isotherms well. The adsorption capacity increased with increasing temperature between 20°C and 70°C. Between 70°C and 90°C, the adsorption capacity decreased obviously with increasing temperature. The adsorption capacity reached the maximum at 70°C. By analyzing the results of the kinetics and the thermodynamics, we found that the adsorption of PH was dominated by physical adsorption at the lower temperature (20°C). Then with increasing temperature, chemical adsorption gradually dominated in the adsorption process. The adsorption capacity decreased at above 70°C is due to the exothermic effects in the process of adsorption.

关键词： adsorption PH₃ activated carbon kinetics thermodynamics

HTML PDF 收藏

Contributions of adsorption, bioreduction and desorption to uranium immobilization by extracellular polymeric

《环境科学与工程前沿（英文）》 2023年第17卷第9期 doi: 10.1007/s11783-023-1707-z

摘要：

● EPS immobilizes U(VI) via adsorption, bioreduction and desorption.

关键词： Adsorption Bioreduction Desorption Kinetics Isotherm Uranium

HTML PDF 收藏

Efficient CO

Yanxia Wang, Xiude Hu, Tuo Guo, Jian Hao, Chongdian Si, Qingjie Guo

《化学科学与工程前沿（英文）》 2021年第15卷第3期页码 493-504 doi: 10.1007/s11705-020-1967-0

摘要： In this work, nitrogen-doped porous carbons (NACs) were fabricated as an adsorbent by urea modification and KOH activation. The CO adsorption mechanism for the NACs was then explored. The NACs are found to present a large specific surface area (1920.72–3078.99 m ·g ) and high micropore percentage (61.60%–76.23%). Under a pressure of 1 bar, sample NAC-650-650 shows the highest CO adsorption capacity up to 5.96 and 3.92 mmol·g at 0 and 25 °C, respectively. In addition, the CO /N selectivity of NAC-650-650 is 79.93, much higher than the value of 49.77 obtained for the nonnitrogen-doped carbon AC-650-650. The CO adsorption capacity of the NAC-650-650 sample maintains over 97% after ten cycles. Analysis of the results show that the CO capacity of the NACs has a linear correlation ( = 0.9633) with the cumulative pore volume for a pore size less than 1.02 nm. The presence of nitrogen and oxygen enhances the CO /N selectivity, and pyrrole-N and hydroxy groups contribute more to the CO adsorption. Fourier transform infrared spectra analysis indicates that CO is adsorbed onto the NACs as a gas. Furthermore, the physical adsorption mechanism is confirmed by adsorption kinetic models and the isosteric heat, and it is found to be controlled by CO diffusion. The CO adsorption kinetics for NACs at room temperature and in pure CO is in accordance with the pseudo-first-order model and Avramís fractional-order kinetic model.

关键词： porous carbon CO₂ adsorption nitrogen-doped adsorption mechanism kinetics

HTML PDF 收藏

Removal of Rhodamine B from aqueous solutions and wastewater by walnut shells: kinetics, equilibrium

Jasmin Shah, M. Rasul Jan, Attaul Haq, Younas Khan

《化学科学与工程前沿（英文）》 2013年第7卷第4期页码 428-436 doi: 10.1007/s11705-013-1358-x

摘要： An adsorption study of Rhodamine B (RB) dye from aqueous solutions was carried out using walnut shells pretreated by different methods. In addition to the effects of the pretreatment, the effects of various parameters like pH, adsorbent dose, contact time, initial dye concentration and temperature on the adsorption of RB was studied. The adsorption process was highly pH dependent and a maximum adsorption was achieved at pH 3.0. The best fit for the rates of dye adsorption was a pseudo-second-order kinetic model with good correlation coefficients ( >0.99). Langmuir isotherms were used to determine that the maximum loading capacity of the different walnut shells and the RB capacities ranged from 1.451–2.292 mg·g . The dye adsorption was also evaluated thermodynamically. Positive standard enthalpy (? °) values were obtained indicating that the RB adsorption process is endothermic as well as ? ° and ? ° values showed that adsorption process is spontaneous with an increased randomness at the solid-liquid interface. Desorption studies were carried out to explore the feasibility of regenerating the used walnut shells and it was found that 97.71%–99.17% of the retained RB was recovered with 0.1 mol?L NaOH solution. The walnut shells were also successfully used to remove RB from industrial effluents.

关键词： Rhodamine B walnut shell adsorption kinetics isotherms regeneration

HTML PDF 收藏

Effect of the degree of template removal from mesoporous silicate materials on their adsorption of heavy

Farouq TWAIQ,M.S. NASSER,Sagheer A. ONAIZI

《化学科学与工程前沿（英文）》 2014年第8卷第4期页码 488-497 doi: 10.1007/s11705-014-1459-1

摘要： The key aim of this study is to evaluate the adsorption of heavy oil from aqueous solutions with different oil contents over mesoporous silicate materials having different surfactant template contents. The mesoporous silicate materials have been synthesized from tetraethylorthosilicate as a silica precursor and cetyltrimethylammonium bromide as a template using the sol-gel technique. Four samples were prepared by (1) totally removing the template using the calcination process, (2) partially removing the template via ethanol extraction, (3) partially removing the template via water extraction, and (4) keeping the template as synthesized, respectively. These four samples have been characterized using X-ray diffraction, nitrogen adsorption, thermal gravimetric analysis and Fourier transformed infrared. The effect of the degree of template removal of these mesoporous materials for the oil removal has been investigated. The oil removal is inversely proportional to the surfactant content in the mesoporous material, being highest for the calcined sample but lowest for the as-synthesized sample. The kinetic of oil adsorption over the calcined material has been also studied and the data obtained fit well a second-order model.

关键词： heavy oil mesoporous silicate material kinetics template removal adsorption

HTML PDF 收藏

The influence of chlorinated aromatics' structure on their adsorption characteristics on activated carbon

Pengfei LIN,Yuan ZHANG,Xiaojian ZHANG,Chao CHEN,Yuefeng XIE,Irwin H SUFFET

《环境科学与工程前沿（英文）》 2015年第9卷第1期页码 138-146 doi: 10.1007/s11783-014-0725-2

摘要： This study focused on evaluating the efficiency of powdered activated carbon (PAC) adsorption process and tackling chlorobenzenes and chlorophenols spill in drinking water source. The adsorption kinetics and PAC’s capacities for five chlorobenzenes and three chlorophenols at drinking water contamination levels were studied in order to determine the influence of different functional groups on the adsorption behavior. The results showed that PAC adsorption could be used as an effective emergency drinking water treatment process to remove these compounds. The adsorption kinetics took 30 min to achieve nearly equilibrium and could be described by both pseudo first-order and pseudo second-order models. A mathematic relationship was developed between the pseudo first-order adsorption rate constant, k , and the solutes’ properties including lg , polarizability and molecular weight. The Freundlich isotherm equation could well describe the adsorption equilibrium behaviors of chlorinated aromatics with from 0.920 to 0.999. The H-bond donor/acceptor group, hydrophobicity, solubility and molecular volume were identified as important solute properties that affect the PAC adsorption capacity. These results could assist water professionals in removing chlorinated aromatics during emergency drinking water treatment.

关键词： chlorinated aromatics adsorption powdered activated carbon kinetics equilibrium

HTML PDF 收藏

Facile synthesis of α-MnO

Weixin ZHANG, Wenran ZHAO, Zaoyuan ZHOU, Zeheng YANG

《化学科学与工程前沿（英文）》 2014年第8卷第1期页码 64-72 doi: 10.1007/s11705-014-1402-5

摘要： In this paper, α-MnO micronests composed of nanowires were fabricated via a hydrothermal reaction of MnSO ·H O and K S O solutions. The α-MnO micronests were demonstrated to have a higher adsorption capacity than γ-MnO microspheres due to their large specific surface area. The amount of Congo red adsorbed per unit weight of α-MnO micronests increased significantly from 114 to 282 mg·g with concentration of Congo red solution increasing from 50 to 200 mg·L , but it had a little change with temperature. Kinetics, isotherms and thermodynamics for the adsorption of Congo red on α-MnO micronests were examined. The adsorption process followed the pseudo-second-order kinetics with good correlation. The experimental data were analyzed by Langmuir and Freundlich models, and equilibrium data fitted the Langmuir isotherm very well with maximum monolayer adsorption capacity of 625 mg·g at 22 °C. The adsorption was spontaneous and endothermic according to thermodynamic studies. The experimental results indicate that α-MnO micronests possess a high adsorption capacity and could be employed as a replacement of traditional sorbents.

关键词： MnO₂ Congo red adsorption kinetics isotherm thermodynamics

HTML PDF 收藏

Kinetics of enhanced adsorption by polarization for organic pollutants on activated carbon fiber

HAN Yanhe, QUAN Xie, ZHAO Huimin, CHEN Shuo, ZHAO Yazhi

《环境科学与工程前沿（英文）》 2007年第1卷第1期页码 83-88 doi: 10.1007/s11783-007-0016-2

摘要： The adsorption kinetics for model pollutants on activated carbon fiber (ACF) by polarization was investigated in this work. Kinetics data obtained for the adsorption of these model pollutants at open-circuit, 400 mV, and -400 mV polarization were applied to the Lagergren equation, and adsorption rate constants () were determined. With the anodic polarization of 400 mV, the capacity of sodium phenoxide was increased from 0.0083 mmol/g at open-circuit to 0.18 mmol/g, and a 17-fold enhancement was achieved; however, the capacity of -nitrophenol was decreased from 2.93 mmol/g at open-circuit to 2.65 mmol/g. With the cathodal polarization of -400 mV, the capacity of aniline was improved from 3.60 mmol/g at open-circuit to 3.88 mmol/g; however, the capacity of sodium dodecylbenzene sulfonate was reduced from 2.20 mmol/g at open-circuit to 1.59 mmol/g. The enhancement for electrosorption changed with dif ferent groups substituting. Anodic polarization enhances the adsorption of benzene with the electron-donating group. But whether anodic or not, cathodal polarization had less effect on the adsorption of electron-accepting aromatic compounds, and decreased the adsorption capacity of benzene-bearing donor-conjugate bridge-acceptor, while increasing its adsorption rate. Electrostatic interaction played a very important role in the electrosorption of ion-pollutants.

关键词： ACF activated 17-fold enhancement donor-conjugate bridge-acceptor Electrostatic interaction

HTML PDF 收藏

Removal of phenol by powdered activated carbon adsorption

Yan MA, Naiyun GAO, Wenhai CHU, Cong LI

《环境科学与工程前沿（英文）》 2013年第7卷第2期页码 158-165 doi: 10.1007/s11783-012-0479-7

摘要： In this study, the adsorption performance of powdered activated carbon (PAC) on phenol was investigated in aqueous solutions. Batch adsorption studies were performed to evaluate the effects of various experimental parameters like PAC type, PAC dose, initial solution pH, temperature and pre-oxidation on the adsorption of phenol by PAC and establish the adsorption kinetics, thermodynamics and isothermal models. The results indicated that PAC adsorption is an effective method to remove phenol from water, and the effects of all the five factors on adsorption of phenol were significant. The adsorption rate of phenol by PAC was rapid, and more than 80% phenol could be absorbed by PAC within the initial 10 min. The adsorption process can be well described by pseudo-second-order adsorption kinetic model with rate constant amounted to 0.0313, 0.0305 and 0.0241 mg·μg ·min with coal, coconut shell and bamboo charcoal. The equilibrium data of phenol absorbed onto PAC were analyzed by Langmuir, Freundlich and Tempkin adsorption isotherms and Freundlich adsorption isotherm model gave the best correlation with the experimental data. Thermodynamic parameters such as the standard Gibbs free energy (? ), enthalpy (? ) and entropy (? ) obtained in this study indicated that the adsorption of phenol by PAC is spontaneous, exothermic and entropy decreasing.

关键词： phenol powdered activated carbon adsorption kinetics isotherms

HTML PDF 收藏

DK型纳滤膜对水中微量邻苯二甲酸酯的吸附及截留特性

金叶,吴礼光,张林

《中国工程科学》 2014年第16卷第7期页码 36-41

摘要：

邻苯二甲酸酯（PAEs）是一类典型的环境激素，对人体健康具有较大的危害。本文采用DK型纳滤膜去除水中微量邻苯二甲酸酯，分析了水中微量邻苯二甲酸二甲酯(DMP)、邻苯二甲酸二乙酯(DEP)、邻苯二甲酸正二丁酯(DNBP)和邻苯二甲酸异二丁酯(DIBP)等在DK型纳滤膜表面的吸附行为，考察了4 种邻苯二甲酸酯的辛醇/水分配系数(logK_ow)和相对分子质量(M_w)对其在DK型纳滤膜表面的吸附和膜的截留特性的影响。结果表明Freundlich 吸附方程能较好地描述4 种邻苯二甲酸酯在DK型纳滤膜表面的动态吸附行为；DK型纳滤膜对水中微量邻苯二甲酸酯的截留特性表现为膜面吸附作用和膜孔筛分效应，吸附平衡后的截留机理取决于膜孔的筛分效应，DK型纳滤膜对DMP、DEP、DNBP、DIBP的截留率分别为55 %、78 %、96 %和96.8 % (0.5 MPa，30 ℃，DMP、DEP、DNBP、DIBP浓度均为300 μg/L)，表明DK型纳滤膜能高效去除水中的DNBP和DIBP。

关键词：邻苯二甲酸酯纳滤吸附截留

HTML PDF 收藏

carbon-hybridized and amine-modified polyacrylonitrile nanofibers toward ultrahigh and recyclable metal ion and dye adsorption

Fengli Li, Chuang Chen, Yuda Wang, Wenpeng Li, Guoli Zhou, Haoqin Zhang, Jie Zhang, Jingtao Wang

《化学科学与工程前沿（英文）》 2021年第15卷第4期页码 984-997 doi: 10.1007/s11705-020-2000-3

摘要： Nanofibers with high specific surface area and chemical stability have broad prospects in the applications of adsorption. However, the adsorption capacity is limited by the scarcity of adsorption groups and storage space. Herein, the activated carbon-hybridized and amine-modified nanofibers are prepared by integrating activated carbon (AC) and polyacrylonitrile (PAN) via electrospinning method and the subsequent amination, which could provide additional storage space and adsorption groups for ultrahigh adsorption capability. Thus, the obtained amine-rich porous PAN nanofibers (APAN/AC) readily realized the ultrahigh adsorption capacity for metal ions and dyes in wastewater. Specifically, the adsorption capacity of APAN/AC nanofibers were 284 mg·g for Cr(VI) and 248 mg·g for methyl orange, which were almost 2 and 4 times than that of amine-modified nanofibers (APAN) and carbon-hybridized nanofibers (PAN/AC), respectively. Moreover, the AC inhibited the chain mobility of polymer matrix and thereby endowing APAN/AC nanofibers with excellent recyclability. The adsorption capability retained 80% after nine adsorption-desorption cycles. The adsorption kinetics and corresponding mechanism were further explored. This strategy combines the advantages of polymer nanofibers and AC, opening a new avenue for developing next-generation absorbent materials.

关键词： carbon-hybridized and amine-modified nanofibers polyacrylonitrile metal ions and dyes wastewater adsorption kinetics

HTML PDF 收藏

Removal of sulfadiazine from aqueous solution on kaolinite

Jian XU, Yan HE, Yuan ZHANG, Changsheng GUO, Lei LI, Yuqiu WANG

《环境科学与工程前沿（英文）》 2013年第7卷第6期页码 836-843 doi: 10.1007/s11783-013-0513-4

摘要： The adsorption of sulfadiazine onto kaolinite clay as an alternative adsorbent was examined in aqueous solution. Impacts of the contact time, pH, temperature, ionic strength and coexistent surfactants on the adsorption process were evaluated. The pH significantly influenced the adsorption process, with adsorption being promoted at lower pH due to the cation exchange mechanism. Decreasing ionic strength in the solution was favorable for adsorption, and the addition of cationic and anionic surfactants had negative effects on the adsorption capacity of sulfadiazine on kaolinite. Kinetic experiments showed that the adsorption followed the pseudo-second-order model. The equilibrium adsorption was well described by both Freundlich and Dubinin-Radushkevich (DR) models. According to the DR model, the adsorption mechanism was determined by cationic exchange and weak physical forces. The thermodynamic study showed that sulfadiazine adsorption onto kaolinite was a spontaneous and endothermic reaction.

关键词： adsorption kaolinite sulfadiazine kinetics

HTML PDF 收藏

Preparation and characterization of

Chunhua XU, Dandan CHENG, Baoyu GAO, Zhilei YIN, Qinyan YUE, Xian ZHAO

《环境科学与工程前沿（英文）》 2012年第6卷第4期页码 455-462 doi: 10.1007/s11783-010-0275-1

摘要： Batch adsorption experiments were conducted to explore the adsorption of Cr(VI) in aqueous solutions by -FeOOH-coated sand. We investigated the key factors which affected the adsorption process such as adsorbent dosage, initial pH, initial Cr(VI) ion concentration, contact time and temperature. The uptake of Cr(VI) was very rapid and 44.3%, 51.6%, 58.9% of the adsorption happened during the first 180 minutes at 293K, 303K and 313K, respectively. The pseudo-second-order rate equation successfully described the adsorption kinetics. To study the adsorption isotherm, two equilibrium models, the Langmuir and Freundlich isotherms, were adopted. At 293K, 303K and 313K, the adsorption capacities obtained from the Langmuir isotherm were 0.060, 0.070 and 0.076 mg Cr(VI) per gram of the adsorbent, respectively. Thermodynamic parameters such as the change of energy, enthalpy and entropy were calculated using the equilibrium constants. The negative value of and the positive value of showed that the adsorption of Cr(VI) in aqueous solutions by -FeOOH-coated sand was spontaneous, endothermic and occurred by physisorption.

关键词： β-FeOOH-coated sand Cr(VI) adsorption isotherm kinetics

HTML PDF 收藏

Theoretical insights into influence of additives on sulfamethoxazole crystal growth kinetics and mechanisms

《化学科学与工程前沿（英文）》 2023年第17卷第10期页码 1503-1515 doi: 10.1007/s11705-022-2294-4

摘要： In this work, the influence of the initial chemical potential gradient, stirring speed, and polymer type on sulfamethoxazole (SMX) crystal growth kinetics was systematically investigated through density functional theory (DFT) calculations, experimental measurements and the two-step chemical potential gradient model. To investigate the influence of different conditions on the thermodynamic driving force of SMX crystal growth, SMX solubilities in different polymer solutions were studied. Four model polymers effectively improved SMX solubility. It was further found that polyvinylpyrrolidone (PVP) and hydroxypropyl methyl cellulose (HPMC) played a crucial role in inhibiting SMX crystal growth. However, polyethylene glycol (PEG) promoted SMX crystal growth. The effect of the polymer on the crystal growth mechanisms of SMX was further analyzed by the two-step chemical potential gradient model. In the system containing PEG 6000, crystal growth is dominated by the surface reaction. However, in the system containing PEG 20000, crystal growth is dominated by both the surface reaction and diffusion. In addition, DFT calculations results showed that HPMC and PVP could form strong and stable binding energies with SMX, indicating that PVP and HPMC had the potential ability to inhibit SMX crystal growth.

关键词： insoluble drugs polymer inhibition crystallization crystal growth kinetics DFT calculations

HTML PDF 收藏

Combustion characteristics and kinetics of bio-oil

Ruixia ZHANG, Zhaoping ZHONG, Yaji HUANG

《化学科学与工程前沿（英文）》 2009年第3卷第2期页码 119-124 doi: 10.1007/s11705-009-0068-x

摘要： The combustion characteristics of bio-oils derived from rice husk and corn were studied by thermogravimetry analysis. According to the thermogravimetry (TG), differential thermogravimetry (DTG) and differential thermal analysis (DTA) curves of bio-oils in air and nitrogen atmosphere, we analyzed the combustion characteristics of different kinds of bio-oils in different atmospheres and worked out the combustion kinetics parameters of the bio-oil, providing reliable base data for the burning of bio-oil. The thermogravimetry indicated that the combustion process of bio-oil was divided into three stages. At the same time, the combustion process can be described by different order reaction models, and with the method of Coats-Redfern, the activation energy and frequency factor of different kinds of bio-oils were obtained.

关键词： bio-oil combustion characteristics combustion kinetics