Functionalized Membranes For Environmental Remediation And Selective Separation,
2014
University of Kentucky
Functionalized Membranes For Environmental Remediation And Selective Separation, Li Xiao
Theses and Dissertations--Chemical and Materials Engineering
Membrane process including microfiltration (MF), ultrafiltration (UF), nanofiltration (NF) and reverse osmosis (RO) have provided numerous successful applications ranging from drinking water purification, wastewater treatment, to material recovery. The addition of functional moiety in the membranes pores allows such membranes to be used in challenging areas including tunable separations, toxic metal capture, and catalysis. In this work, polyvinylidene fluoride (PVDF) MF membrane was functionalized with temperature responsive (poly(N-isopropylacrylamide), PNIPAAm) and pH responsive (polyacrylic acid, PAA) polymers. It’s revealed that the permeation of various molecules (water, salt and dextran) through the membrane can be thermally or pH controlled. The introduction of …
Layer-By-Layer Assemblies For Membrane-Based Enzymatic Catalysis,
2014
University of Kentucky
Layer-By-Layer Assemblies For Membrane-Based Enzymatic Catalysis, Andrew R. Tomaino
Theses and Dissertations--Chemical and Materials Engineering
While considerable progress has been made towards understanding the effect that membrane-based layer-by-layer (LbL) immobilizations have on the activity and stability of enzymatic catalysis, detailed work is required in order to fundamentally quantify and optimize the functionalization and operating conditions that define these properties. This work aims to probe deeper into the nature of transport mechanisms by use of pressure-induced, flow-driven enzymatic catalysis of LbL-functionalized hydrophilized poly(vinyldiene) (PVDF)-poly(acrylic acid) (PAA)-poly(allylamine hydrochloride) (PAH)-glucose oxidase (GOx) membranes. These membranes were coupled in a sealed series following cellulose acetate (CA) membranes for the elimination of product accumulation within the feed-side solution during operation. …
Evaluating N-Benzylgalactonoamidines As Putative Transition State Analogs For Β-Galactoside Hydrolysis,
2014
University of Arkansas, Fayetteville
Evaluating N-Benzylgalactonoamidines As Putative Transition State Analogs For Β-Galactoside Hydrolysis, Qui-Hua Fan, Susanne Striegler, Rebekah Langston, James Barnett
Chemistry & Biochemistry Faculty Publications and Presentations
Experimental evidence is provided for p-methylbenzyl-D-galactonoamidine to function as a true transition state analog for the enzymatic hydrolysis of aryl-β-D-galactopyranosides by β-galactosidase (A. oryzae). The compound exhibits inhibition constants in the low nanomolar concentration range (12–56 nM) for a selection of substrates. Along these lines, a streamlined synthetic method based on phase-transfer catalysis was optimized to afford the required variety of new aryl-β-D-galactopyranosides. Last, the stability of the galactonoamidines under the assay conditions was confirmed.
Controllable Synthesis Of Dispersed Spherical Fe3O4 Nanoparticles As Lithium-Inserted Materials,
2013
Engineering Research Center of Materials and Technology for Electrochemical Energy Storage (Ministry of Education), School of Chemistry and Environment, South China Normal University, Guangzhou 510006, China;
Controllable Synthesis Of Dispersed Spherical Fe3O4 Nanoparticles As Lithium-Inserted Materials, Hong-Li Zou, Wei-Shan Li
Journal of Electrochemistry
Dispersed spherical Fe3O4 nanoparticles were synthesized by a hydrothermal method. The influences of odecyl trimethyl ammonium bromide (DTAB) concentration on the morphology and particle size of the as-prepared Fe3O4 were studied. Electrochemical performance of the as-prepared sample as anode materials of lithium ion battery was investigated. It is found that the as-prepared sample exhibits superior rate performance and cycle performance. The nano-sized materials provide structural stability and favor the transfer of lithium ions.
Synthesis And Electrochemical Performance Of Nano Licopo4 By Polyol Method,
2013
School of Chemistry and Chemical Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
Synthesis And Electrochemical Performance Of Nano Licopo4 By Polyol Method, Fei Wang, Yang Jun
Journal of Electrochemistry
High potential LiCoPO4 cathode material was synthesized by polyol method. Carbon layer of ca. 3 nm thick was coated on the LiCoPO4 surfaces by chemical vapor deposition from methylbenzene. Crystalline structure, morphology and electrochemical performance of the sample were studied by XRD, SEM, TEM, CV and galvanostatic charge/discharge curve. The synthesized material via polyol method showed a pure phase of LiCoPO4. The LiCoPO4/C electrode delivered a high discharge capacity of 132 mAh·g-1 and maintained 78% of the initial capacity after 50 cycles at 0.1C rate. The two-step extraction/insertion behavior of Li+ in …
Aqueous Solution-Evaporation Route Synthesis And Phase Structural Research Of The Li-Rich Cathode Li1.23Ni0.09Co0.12Mn0.56O2 By In-Situ Xrd,
2013
Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Fujian Xiamen 361005;
Aqueous Solution-Evaporation Route Synthesis And Phase Structural Research Of The Li-Rich Cathode Li1.23Ni0.09Co0.12Mn0.56O2 By In-Situ Xrd, Chong-Heng Shen, Shou-Yu Shen, Zhou Lin, Xiao-Mei Zheng, Hang Su, Ling Huang, Jun-Tao Li, Shi-Gang Sun
Journal of Electrochemistry
The Li-rich Li1.23Ni0.09Co0.12Mn0.56O2 material was synthesized via aqueous solution-evaporation route. The structure and morphology of the material were characterized by means of XRD and SEM. The results indicated that the single particle of the product was polygonal with the size of 330 nm and the structure was layered solid solution with a certain amount of Li2MnO3. Electrochemical tests showed that the first discharge capacity of the Li-rich layered material was 250.8 mAh·g-1 at 0.1C, the capacity retention was 86.5% after 40 cycles. Through in-situ XRD study …
Synthesis And Electrochemical Property Of Li2Fesio4/C Cathode Material By Solid State Method,
2013
School of Chemistry and Material Science, Guizhou Normal University, Guiyang 550001, Guizhou, China;
Synthesis And Electrochemical Property Of Li2Fesio4/C Cathode Material By Solid State Method, Jiao-Li Sun, Zhi-Jiao Chen, Yi-Xiao Li, Hu Cheng
Journal of Electrochemistry
Li2FeSiO4/C cathode material was synthesized using Li2SiO3 and FeC2O4 as raw materials by solid state method. The structure and morphology of the material were characterized by XRD and SEM. The electrochemical properties of the material were studied by constant-current cyclic testing. The results show that Li2FeSiO4/C has a good electrochemical performance. The first discharge capacity of Li2FeSiO4/C cathode material at 30oC reached 167 mAh∙g-1 when cycled at 10 mA∙g-1 between 1.5 and 4.8 V.
Synthesis Of Pani/Nihcf Nanocomposite Particles And Eqcm Measurement Of Ion Exchange Properties In Solutions Containing Cd2+,
2013
Department of Chemical Engineering, Taiyuan University of Technology, Taiyuan 030024, China;
Synthesis Of Pani/Nihcf Nanocomposite Particles And Eqcm Measurement Of Ion Exchange Properties In Solutions Containing Cd2+, Yu-Jiao Yang, Xiao-Gang Hao, Xu-Li Ma, Zhong-De Wang, Zhong-Lin Zhang, Nian-Chen Han
Journal of Electrochemistry
The PANI/NiHCF nanocomposite particles were synthesized on the CNTs-modified Pt substrate by one-step co-polymerization using cyclic voltammetry. Electrochemical quartz crystal microbalance (EQCM) technique was adopted to investigate the polymerization process of the nanocomposite particles and the mechanism of ion exchange in aqueous solution containing Cd2+. The morphology and structure of the as-prepared composite particles were characterized by scanning electron microscope (SEM), transmission electron microscope (TEM), and Fourier transform infrared spectroscopy (FT-IR). Combined with cyclic voltammetry (CV) and energy dispersive spectroscopy (EDS), the electrochemical behavior and the mechanism of ion exchange were also investigated in electrolytes of Cd2+ …
A Comparative Study In Pretreatments Of Acid Chemical Wastewater By Electrochemical Oxidation And Ozonation,
2013
College of Chemical Engineering and Materials Science, State Key Laboratory Breeding Base of Green Chemistry-Synthesis Technology, Zhejiang University of Technology, Hangzhou 310032,China;
A Comparative Study In Pretreatments Of Acid Chemical Wastewater By Electrochemical Oxidation And Ozonation, Han-Shui Liu, Su Yu, Shao-Ping Tong, Chun-An Ma
Journal of Electrochemistry
Under the condition of keeping certain acidity, the pretreatment efficiency of an acid chemical wastewater (pH 0.85) by electrochemical oxidation was compared with that by ozonation. The results showed that the electrochemical oxidation pretreatment could obtain a better result than the ozonation at pH 0.85. After the addition of 2 g·L-1 NaCl and with the electrochemical oxidation pretreatment at 30 mA·cm-2, the removal rate of chemical oxygen demand (CODCr) reached 43.4%, and the value of biochemical oxygen demand/chemical oxygen demand (BOD5/CODCr) also increased from 0.034 to 0.14 in 20 minutes, indicating significantly improvement …
Preparation Of Benzoquinone From Phenol By Electrooxidation,
2013
State Key Laboratory of Chemical Engineering, East China University of Science and Technology, Shanghai 200237, China;
Preparation Of Benzoquinone From Phenol By Electrooxidation, Dong-Fang Niu, Cheng-Kai Yu, Xin-Sheng Zhang
Journal of Electrochemistry
The benzoquinone was prepared from phenol by electrooxidation in an H-type cell with cation exchange membrane, in which lead plates were used both as an anode and a cathode, while H2SO4 was used as a supporting electrolyte. The effects of current density, concentration of sulphuric acid, concentrations of benzoquinone in electrolyte and extractant on the yields and efficiencies of electrolysis were investigated. Under the optimized conditions of current density being 4 A·dm-2, concentration of sulphuric acid 1 mol·L-1, passed charge 3.2 A·h, the yield and current efficiency of benzoquinone could reach 68% and …
Experimental Design Methodology Applied To The Oxidation Of Quinolines In Aqueous Medium By Electro-Fenton Process,
2013
Université Paris-Est, Laboratoire Géomatériaux et Environnement (LGE), UPEMLV, 77454 Marne-la-Vallée, France;Laboratoire de Chimie Analytique et Electrochimie, Département de Chimie, Faculté des Sciences de Tunis, Campus Universitaire 2092, El Manar Tunis, Tunisia;
Experimental Design Methodology Applied To The Oxidation Of Quinolines In Aqueous Medium By Electro-Fenton Process, Souhaila Trabelsi Souissi, Nihal Oturan, Nizar Bellakhal, Mehmet A. Oturan
Journal of Electrochemistry
The degradation behavior of 8-hydroxyquinoleine sulfate (8-HQS), a model molecule of quinolines, was studied in an aqueous medium by electro-Fenton process using a carbon felt cathode and a platinum anode. The great oxidation ability of this process is due to a large production of hydroxyl radical (OH) by electrochemically induced Fenton’s reagent (H2O2, Fe2+). Hydroxyl radicals are very powerful oxidizing agents which react on organics up to complete mineralization. A factorial experimental design was used for determining the operating parameters on the degradation of 8-HQS in an aqueous medium. The results showed that the …
Experimental Study Of Co2 Recycling Using Metal-Oxide Enhanced Coconut Char Gasification: Catalytic Effect Of Potassium Carbonate On Gasification,
2013
Purdue University
Experimental Study Of Co2 Recycling Using Metal-Oxide Enhanced Coconut Char Gasification: Catalytic Effect Of Potassium Carbonate On Gasification, Mengqi Gao, Indraneel Sircar, Jay P. Gore
The Summer Undergraduate Research Fellowship (SURF) Symposium
Biomass gasification is an important process in the production of bio-derived fuels and renewable energy. Biomass gasification with CO2 is an endothermic process requiring high temperatures, resulting in low process-efficiency. Metals found in the ash in biomass feedstock have shown rate-promoting effects on the C-CO2 reaction and have motivated the study of low-temperature catalytic gasification. The present study investigates the catalytic effects of potassium (K) on the biomass gasification reactivity of a coconut-derived char (>99.9% carbon) within the temperature range of 600 – 1000 oC. A wet-impregnation technique is used to prepare K-treated chars. Gasification of …
Electrosynthesis Of Glycerol Carbonate From Co2 And Glycerol,
2013
Shanghai Key Laboratory of Green Chemistry and Chemical Process, Department of Chemistry, East China Normal University, Shanghai 200062, China;
Electrosynthesis Of Glycerol Carbonate From Co2 And Glycerol, Huan Wang, Mei-Xia Zhu, La-Xia Wu, Xiao-Ming Xu, Xue-Ru Zhao, Jia-Xing Lu
Journal of Electrochemistry
Glycerol carbonate was obtained from glycerol and carbon dioxide under room temperature and normal pressure by electrochemical method. The effects of synthesis conditions, such as cathode, charge, current density and temperature, on the reaction of glycerol and carbon dioxide have been investigated. The yields of 73% were produced by electrosynthesis of carbonate under the optimized condition, which is much higher than that by common catalysis method. The electrochemical behavior of the reaction system has been studied by cyclic voltammetry, through which the reaction process has been proposed.
Influence Of Pretreatment On Electrocatalytic Property For Methanol Oxidation Of Ptru/Wc,
2013
State Key Laboratory Breeding Base of Green Chemistry Synthesis Technology, College of Chemical Engineering and Materials Science, Zhejiang University of Technology, Hangzhou 310032, China;
Influence Of Pretreatment On Electrocatalytic Property For Methanol Oxidation Of Ptru/Wc, Xiao-Ling Lang, Mei-Qin Shi, Ye-Kun Jiang, Chun-An Ma
Journal of Electrochemistry
The surface of tungsten carbide (WC) was treated by potassium hydroxide (KOH) at different pH values for different time. The PtRu/WC composite was prepared by microwave-assisted polyol method. The phase structure of PtRu/WC composites were characterized by XRD. The electrocatalytic activity was tested by cyclic voltammetry and chronoamperometry. The results indicated that with different pH treatments WC became more readily supported on PtRu. When treating WC in KOH at pH = 14, PtRu exhibited the best degree of crystallinity on WC surface, leading to the highest electrocatalytic activity of PtRu/WC. Moreover, the optimized activity of PtRu/WC towards methanol oxidation was …
Synthesis And Electrochemical Properties Of Li(Ni0.5Co0.2Mn0.3)1-2xTiXNbXO2,
2013
Zhaoqing Fenghua Lithium Battery Co., Ltd, Zhaoqing Guangdong, China, 526040;
Synthesis And Electrochemical Properties Of Li(Ni0.5Co0.2Mn0.3)1-2xTiXNbXO2, Yong Tang, Qin-Lin Liao, Xiang-An Guo
Journal of Electrochemistry
The cathode-active materials of layered Li(Ni0.5Co0.2Mn0.3)1-2xTixNbxO2(x=0, 0.002, 0.005, 0.01, 0.02)composites were synthesized by the thermal treatment of the coprecipitated precursor at 900 oC in air. The effects of Ti-Nb co-dopants on the structural and electrochemical properties of Li(Ni0.5Co0.2Mn0.3)O2 were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and electrochemical experiments. The results show that the small amounts of Ti-Nb co-dopants in Li(Ni0.5Co0.2Mn0.3)O2significantly decreased the degree of cation mixing in …
Research Progress Of Intermediate Layers In Ti-Based Oxide Anodes,
2013
College of Chemistry and Chemical Engineering, Taiyuan University of Technology, Taiyuan 030024, China;Department of Chemistry, Taiyuan Normal University, Taiyuan 030031, China;
Research Progress Of Intermediate Layers In Ti-Based Oxide Anodes, Xiu-Li Song, Hui-Min Yang, Zhen-Hai Liang
Journal of Electrochemistry
Titanium (Ti)-based oxide anodes are excellent anode materials which have been applied widely in electrochemical fields all over the world. Adding intermediate layers in Ti-based oxide anodes can improve the conductivity, lengthen the lifetime and strengthen the stability between Ti base and metal oxides active layers of electrodes. This article reviews the research progress of intermediate layers in Ti-based oxide anodes. At the same time, current problems existed in the field of Ti-based oxide anodes are pointed out and future development trend in oxide electrode with intermediate layers is prospected.
Advanced Treatment Of Dyeing Wastewater For Reuse By Electrochemical Oxidation,
2013
College of Biological and Environmental Engineering, Zhejiang University of Technology, Hangzhou 310032, China;
Advanced Treatment Of Dyeing Wastewater For Reuse By Electrochemical Oxidation, Fei-Xiang Chen, Chu-Yin Yang, Ming-Ming Zhou, Jia-De Wang
Journal of Electrochemistry
In response to the characteristics of dye wastewater, the electrochemical oxidation of effluents from the biochemical process of dyeing wastewater was studied in the electrochemical reactor using PbO2/Ti electrode as the anode and stainless steel plate as the cathode. The results revealed that the electrochemical oxidation could simultaneously remove the Chemical Oxygen Demand (COD), ammonia and chromaticity. At the residence time of 60 min and current density of 10 mA·cm-2, the COD, ammonia, chromaticity, concentration of chloride ion and pH values could meet the water standards for “the reuse of urban recycling water-water quality standard for …
Voltage Reversal Behavior In Microbial-Anode Fuel Cells,
2013
Jiangsu provincial Key Laboratory of Environmental Materials and Engineering, and Department of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou 225002, China;
Voltage Reversal Behavior In Microbial-Anode Fuel Cells, En-Ren Zhang, Jun-Le Niu, Lei Liu, Guo-Wang Diao
Journal of Electrochemistry
Voltage reversal behavior was investigated in microbial-anode fuel cells (MFCs). Electricity-producing biofilms were developed on the surface of anodes in MFCs inoculated with mixed inoculum from activated sludge. MFC duplicates generally exhibited different performances with respect to the internal resistance, the voltage output and the discharging duration when operating in batch mode. Voltage reversal was observed to occur first in the MFC with lower performance when connecting MFCs in series. Analysis of electrode potentials indicated that the potentials of microbial anodes quickly shifted to more positive values when enhancing discharge current, resulting in voltage reversal in MFCs. Increasing temperature would …
Using Hydrolyzed Sludge Liquor As The Substrate Of Microbial Fuel Cell,
2013
School of Environment, Tsinghua University, Beijing, 100084, China;
Using Hydrolyzed Sludge Liquor As The Substrate Of Microbial Fuel Cell, Peng Liang, Chao Guo, Xia Huang
Journal of Electrochemistry
Hydrolyzed sludge liquor was used as the substrate of microbial fuel cell. When the thermal treatment time increased from 2 h to 96 h, pH varied little between 7.4 and 8.0. When the treatment time increased, the conductivity, COD and alkaline condition increased to 2.53 mS·cm-1, 2520 mg·L-1 and 800 mg·L-1, respectively. Meanwhile, the power density increased to 25 W·m-3. The COD removal increased firstly, then decreased, and finally reached the maximum of 47% at the hydrolyzed time of 6 h. The maximal coulombic efficiency was 71% when the treatment time was 4 …
Electrocatalytic Oxidation Degradation Kinetics Of Oxalic Acid In A Cylindrical Electrochemical Reactor With Ti/Iro2-Ta2O5 Anode,
2013
College of Chemistry, Jilin University, Changchun130021, China;School of Chemistry and Chemical Engineering, Guangxi University, Nanning530004, China;
Electrocatalytic Oxidation Degradation Kinetics Of Oxalic Acid In A Cylindrical Electrochemical Reactor With Ti/Iro2-Ta2O5 Anode, Jing Su, Hai-Bo Lin, Hong Xu, Wei-Min Huang, Ya-Peng He
Journal of Electrochemistry
The electrocatalytic oxidation degradation kinetics of oxalic acid in a cylindrical electrochemical reactor with Ti/IrO2-Ta2O5 as an anode was studied. The relation between instantaneous current efficiency and organic concentration in bulk was established based on the two paths for direct electrochemical oxidations, and the theoretical model was verified by experiments. The experimental resultswere reasonably consistent with the established kinetic model. Furthermore, the competition between the two paths was explored with the modelparameter analysis.
