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颗粒状NiCoO的制备及其在不同电解液中的电化学性能

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环境化学 2024年

作者：杨泛明易志成冯蓉湖南城市学院材料与化学工程学院

本文以NiCl2为镍源、CoCl2为钴源，通过静态水热处理合成NiCo2O4，并对其在6 mol·L-1koh、0.5 mol·L-1K4Fe(CN)6溶液中的赝电容行为进行探究.采用X-射线衍射、X-射线光电子能谱、扫描电子显微镜、透射电子显微镜、能量色散谱和N2吸附... 详细信息

本文以NiCl2为镍源、CoCl2为钴源，通过静态水热处理合成NiCo2O4，并对其在6 mol·L-1koh、0.5 mol·L-1K4Fe(CN)6溶液中的赝电容行为进行探究.采用X-射线衍射、X-射线光电子能谱、扫描电子显微镜、透射电子显微镜、能量色散谱和N2吸附-脱附技术对NiCo2O4的物相、组成、形貌和孔结构进行分析.结果表明，NiCo2O4为立方相多晶材料，并且Ni2+/Ni3+、Co2+/Co3+同时存在于晶格之中.NiCo2O4为颗粒状多孔材料，平均孔径为4.3 nm，孔体积为0.137 cm3·g-1.与K4Fe(CN)6相比较，NiCo2O4在koh溶液中具有更好的倍率充放电性能.扫描速度由5 mV·s-1增大至50 mV·s-1时，NiCo2O4在koh和K4Fe(CN)6溶液中的伏安放电比容量保持率分别为23.7%、17.0%.电流密度由0.5 A·g-1增大至8 A·g-1时，NiCo2O4在koh的放电比容量保持率为31.9%，是其在K4Fe(CN)6溶液中的4.3倍.

关键词： NiCo O koh K Fe(CN) 赝电容

球状NiCoS的制备及其在koh溶液中的电化学行为

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复合材料学报 2024年

作者：龙升刘依邹攀杨泛明贺国文湖南城市学院材料与化学工程学院低碳与环境功能材料湖南省普通高校重点实验室

NiCo2S4中Ni和Co元素可以同时参与充放电过程，获得较高的放电比容量和能量密度。对NiCo2S4中双电层电容和赝电容的贡献率进行分析，有助于推动电极材料的深入开发。以乙酸钴为Co源、乙酸镍为Ni源、硫代乙酰胺为沉淀剂，通过水热合成法... 详细信息

NiCo2S4中Ni和Co元素可以同时参与充放电过程，获得较高的放电比容量和能量密度。对NiCo2S4中双电层电容和赝电容的贡献率进行分析，有助于推动电极材料的深入开发。以乙酸钴为Co源、乙酸镍为Ni源、硫代乙酰胺为沉淀剂，通过水热合成法制备具有优异电化学性能的球状电极材料硫钴酸镍(NiCo2S4)。利用X射线衍射、X射线光电子能谱、扫描电子显微镜、透射电子显微镜、Mapping和N2吸附-脱附技术对NiCo2S4的物相、形貌、组成和孔结构进行分析，并对其在koh电解液中的充放电行为进行探究。结果表明，球状NiCo2S4制备成功，并且Ni、Co和S的比例为1 : 2.1 : 4.2。NiCo2S4为立方相多晶体，晶格常数为0.9387 nm。Ni和Co分别以Ni2+/Ni3+和Co2+/Co3+的形式存在于NiCo2S4的晶格之中。NiCo2S4的孔体积为0.402 cm3/g，并且介孔比例为90.6%。NiCo2S4在koh溶液中同时产生双电层电容和赝电容，两者所占比例分别为60.6%、39.4%。电流密度为0.2 A/g时，放电比容量为409.7 F/g，能量密度为14.2 W·h/kg。循环10000次，容量保持率为90.3%。

关键词： NiCo S koh 球状电容器充放电双电层赝电容

基于K循环的koh活化石油焦制高比表面积活性炭联产氢气

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低碳化学与化工 2024年

作者：王克超徐绍平王雯雯杜利军大连理工大学化工学院

koh活化法制备高比表面积活性炭通常需要消耗大量koh。为提高koh利用效率，开发了一种基于K插层-脱插循环（以下简称“K循环”）的koh活化石油焦制备高比表面积活性炭并联产H2的方法：在升温活化过程，koh与碳质原料反应转化为单质K、K2... 详细信息

koh活化法制备高比表面积活性炭通常需要消耗大量koh。为提高koh利用效率，开发了一种基于K插层-脱插循环（以下简称“K循环”）的koh活化石油焦制备高比表面积活性炭并联产H2的方法：在升温活化过程，koh与碳质原料反应转化为单质K、K2O和K2CO3并析出H2，而K2CO3可继续反应生成单质K和K2O；在降温脱插过程，脱插试剂水蒸气与插层K、游离单质K和K2O反应生成koh和H2；生成的koh在二次升温活化时再次与碳质原料反应，如此构成K循环。在水平舟式反应器中考察了碳质原料种类（石油焦和石墨）、活化剂koh和其活化中间产物K2CO3对活化过程气体产物析出规律和产品活性炭孔隙结构性质的影响，并在此基础上分析了K循环机理。结果表明，K循环效率和H2产量因所用碳质原料与活化剂不同而不同：石油焦的反应活性远高于石墨，koh活化性能优于K2CO3。在koh活化石油焦的K循环过程中，koh转化率达80%，而K2CO3转化率仅18.5%，经由K2CO3的转化环节决定了K循环效率。以石油焦为碳质原料、koh为活化剂，在活化温度为800℃及脱插温度为250℃的条件下，4.5 g干燥后的石油焦与13.5 g koh经二次活化-脱插，所得活性炭比表面积达2808 m2/g，并联产1403 mL/g H2（1 g石油焦产生1403 mL H2）。

关键词：活性炭石油焦 K循环 koh 氢气

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不同K源对NaY分子筛合成的影响

工业催化 2024年第6期32卷 44-49页

作者：赵红娟谢恒刘宇航王久江刘宏海张君屹中国石油石油化工研究院兰州化工研究中心甘肃兰州730060 中国石油兰州石化分公司甘肃兰州730060

通过向水玻璃中添加不同的钾源(KCl和koh),考察其对NaY分子筛合成的影响,并采用XRD、N 2物理吸附-脱附及SEM对样品进行表征。结果表明,当水玻璃中的K+浓度为0.1 mol·L^(-1)时,无论何种K源都不会对NaY分子筛的合成造成影响。而K+浓度增... 详细信息

通过向水玻璃中添加不同的钾源(KCl和koh),考察其对NaY分子筛合成的影响,并采用XRD、N 2物理吸附-脱附及SEM对样品进行表征。结果表明,当水玻璃中的K+浓度为0.1 mol·L^(-1)时,无论何种K源都不会对NaY分子筛的合成造成影响。而K+浓度增加到0.2 mol·L^(-1)时,添加KCl的合成体系中有极少量的杂晶生成,相对结晶度降至74%,进一步增加K+浓度到0.3 mol·L^(-1)、0.4 mol·L^(-1)时,样品中出现了大量的无定型物质。而在添加koh的体系中,相同K添加量下,koh对NaY分子筛的影响要远小于KCl。随着添加量的增加,相对结晶度和比表面积也呈下降趋势。SEM表征结果表明,koh添加量增加到0.3 mol·L^(-1)、0.4 mol·L^(-1)时,合成样品中没有无定形物质形成,但出现了大量菱沸石,说明koh导向生成菱沸石。

关键词：催化剂工程 NaY分子筛 KCl koh K源

Characterization of Formacell Lignin Derived from Black Liquor as a Potential Green Additive for Advanced Biocomposites

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Journal of Renewable Materials 2023年第6期11卷 2865-2879页

作者： Sri Hidayati Eugenia Fonny Budiyanto Hadi Saputra Sutopo Hadi Apri Heri Iswanto Nissa Nurfajrin Solihat Petar Antov Lee Seng Hua Widya Fatriasari MohdSapuan Salit Agricultural Product Technology Department Faculty of AgricultureThe University of LampungJl.Sumantri Brojonegoro No.1Bandar LampungIndonesia Department of Forest Product Faculty of ForestryUniversitas Sumatera UtaraKampus USU Padang BulanNorth SumatraIndonesia JATI-Sumatran Forestry Analysis Study Center Jl.Tridharma Ujung No.1Kampus USUMedanNorth SumatraIndonesia Research Center for Biomass and Bioproducts National Research and Innovation Agency(BRIN)Jl.Raya BogorCibinongIndonesia Faculty of Forest Industry University of ForestrySofiaBulgaria Department of Wood Industry Faculty of Applied SciencesUniversiti Teknologi MARA(UiTM)Cawangan Pahang Kampus JengkaLintasan SemarakBandar JengkaMalaysia Institute of Tropical Forestry and Forest Products Universiti Putra MalaysiaSelangorMalaysia Research Collaboration Center for Marine Biomaterials Jl.Ir.SukarnoJatinangorSumedangWest JavaIndonesia Advanced Engineering Materials and Composites Research Centre Department of Mechanical and Manufacturing EngineeringUniversiti Putra MalaysiaSelangorMalaysia

Black liquor is obtained as a by-product of the pulping process,which is used to convert biomass into pulp by removing lignin,hemicelluloses and other extractives from wood to free cellulose fibers.Lignin represents a major constituent in black liquor,with quantities varying from 20%to 30%,of which a very low share is used for manufacturing value-added products,while the rest is mainly burned for energy purposes,thus underestimating its great potential as a raw material.Therefore,it is essential to establish new isolation and extraction methods to increase lignin valorization in the development of bio-based chemicals.The aim of this research work was to determine the effect of koh or ethanol concentration as an isolation agent on lignin yields and the chemical characteristics of lignin isolated from formacell black liquor of oil palm empty fruit bunch(OPEFB).Isolation of lignin was carried out using koh with various concentrations ranging from 5%to 15%(w/v).Ethanol was also used to precipitate lignin from black liquor at concentrations varying from 5%to 30%(v/v).The results obtained showed that the addition of koh solution at 12.5%and 15%concentrations resulted in better lignin yield and chemical properties of lignin,i.e.,pH values of 3.86 and 4.27,lignin yield of 12.78%and 14.95%,methoxyl content of 11.33%and 10.13%,and lignin equivalent weights of 476.25 and 427.03,respectively.Due to its phenolic structure and rich functional groups that are favorable for modifications,lignin has the potential to be used as a green additive in the development of advanced biocomposite products in various applications to replace current fossil fuel-based material,ranging from fillers,fire retardants,formaldehyde scavengers,carbon fibers,aerogels,and wood adhesives.

关键词： Formacell black liquor lignin properties koh ethanol oil palm empty fruit bunch advanced biocomposite

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高庙子膨润土中蒙脱石碱性溶蚀的矿物学证据

岩土力学 2022年第11期43卷 2973-2982页

作者：童艳梅张虎元周光平李小雅兰州大学土木工程与力学学院甘肃兰州730000 兰州大学西部灾害与环境力学教育部重点实验室甘肃兰州730000

高放废物地下处置库运营过程中,衬砌混凝土在地下水作用下产生的强碱性溶液,会扩散进入膨润土缓冲屏障,长期将使屏障性能发生退化。采用不同pH值的koh溶液模拟衬砌混凝土溶出的碱性溶液,在室内进行为期一年的常温接触扩散试验,开展X射... 详细信息

高放废物地下处置库运营过程中,衬砌混凝土在地下水作用下产生的强碱性溶液,会扩散进入膨润土缓冲屏障,长期将使屏障性能发生退化。采用不同pH值的koh溶液模拟衬砌混凝土溶出的碱性溶液,在室内进行为期一年的常温接触扩散试验,开展X射线荧光光谱(X-ray fluorescence spectroscopy,简称XRF)、X射线衍射(X-ray diffraction,简称XRD)、扫描电镜(scanning electron microscope,简称SEM)和能谱(energy dispersive spectrometry,简称EDS)试验,研究强碱性溶液缓慢扩散对高庙子膨润土矿物的影响。XRF试验结果表明,当koh溶液的pH>12.6时,膨润土中Si元素的含量开始减少,即含Si矿物蒙脱石、石英、方石英等发生了溶解;同时,K元素含量增多,表明膨润土与碱溶液发生离子交换反应,溶液中大量的K+进入蒙脱石层间。XRD试验结果表明,在pH=12.6时,蒙脱石矿物的001峰开始右移、变宽,峰值强度大大减弱;在p H>13时,衍射角θ整体向右偏,晶面间距由原始膨润土样的1.385 3 nm(13.853?)减小为1.221 0 nm(12.210?),表明蒙脱石矿物晶层被压缩。随着koh溶液p H值增大,膨润土中蒙脱石、石英等矿物的含量明显减少,长石类矿物的含量逐渐增加,伊利石和斜发沸石的含量也呈现略微增多的趋势。SEM试验结果表明,随着溶液p H的增大,蒙脱石部分晶层会发生重叠,进而产生部分裂隙和孔洞,加速蒙脱石的溶蚀进程。在为期一年的接触扩散试验中,p H=13.8的koh溶液扩散深度超过7.5 mm,并且在碱溶液与膨润土接触面上观察到新生成的伊利石微晶,证实强碱性溶液会导致蒙脱石溶解及伊利石化。

关键词：膨润土蒙脱石 koh pH 扩散试验溶蚀

Activity and basic properties of koh/mordenite for transesterification of palm oil

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Journal of Energy Chemistry 2013年第5期22卷 690-700页

作者： Pisitpong Intarapong Sotsanan Iangthanarat Pitchaya Phanthong Apanee Luengnaruemitchai Samai Jai-In The Petroleum and Petrochemical College Chulalongkorn University Center of Excellence on Petrochemical and Materials Technology Chulalongkorn University The Royal Thai Navy

The catalytic performance of koh/mordenite has been studied for transesterification of palm oil using a batch reactor and a packed-bed reactor at 60 C and atmospheric pressure.The koh/mordenite processed transesterification in the batch reactor gave the highest methyl ester yield of96.7%under optimum conditions,while a methyl ester content over 94.5%was obtained in the packed-bed reactor.This comparison indicates that transesterification in a batch-type reactor gives a higher methyl ester yield than that of a continuous-flow reactor.Dealumination was found in the calcined catalysts and had a significant effect on the physical structure and chemical composition of the catalysts.Leaching of the potassium species was negligible,whereas depositing and washing of the reacted mixture with acetone on the catalyst surface were observed by FTIR.

关键词： transesterification biodiesel mordenite koh solid base catalyst

Inverse Gas Chromatography Used to Study Lubricating Oil Oxidation Mechanism via Changes in Kovats and Flory-Huggins Retention Parameters

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色谱 2006年第3期24卷 284-289页

作者： MOSTAFA Nagy E EISSA Elham A Egyptian Petroleum Research Institute CairoEgypt

Inverse gas chromatographic technique(IGC) was attempted as a new approach to follow the chem-ical changes that occur during lubricating base oil oxidation.Three groups of the oxidized base oils were pre-pared at different oxygen flow rates,periods and temperatures according to IP48method.The corrected reten-tion volumes(VR) were calculated for a series of selected test solutes possessing different functional groups onthe oxidized base oils used as stationary phases.Kovats retention index(I),Flory-Huggins interaction parame-ter(κ1∞,2),and partial molar free energy of solution(ΔGL∞),were calculated for the given test solutes fromtheirVR.The relationships between theIvalues and the oxidation variables were plotted and discussed.Theobtained results were confirmed by potentiometric titration.The study reveals that the magnitudes of variationofI,κ1∞,2orΔG∞Lretention parameters depend on the oxidation degree of the base oil.Large differences be-tween theIvalues permit discrimination between the different oxidation steps.Key words: inverse gas chromatography(IGC);oxidation;lubricating base oil;Kovats retention

关键词： test IGC koh ASTM rate

Wheat straw pretreatment with koh for enhancing biomethane production and fertilizer value in anaerobic digestion

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Chinese Journal of Chemical Engineering 2016年第3期24卷 404-409页

作者： Muhammad Jaffar Yunzhi Pang Hairong Yuan Dexun Zou Yanping Liu Baoning Zhu Rashid Mustafa Korai Xiujin Li Department of Environmental Science and Engineering Beijing University of Chemical Technology

Wheat straw biodegradability during anaerobic digestion was improved by treatment with potassium hydroxide(koh)to decrease digestion time and enhance biomethane production and fertility value.koh concentrations of1%(K1),3%(K2),6%(K3)and 9%(K4)were tested for wheat straw pretreatment at ambient temperature with a C:N ratio of 25:1.86% of total solids(TS),89% of volatile solids(VS)and 22% of lignocellulose,cellulose and hemicellulose(LCH)(22%)were decomposed effectively with the wheat straw pretreated by 6% koh.Enhanced biogas production and cumulative biomethane yield of 258 ml·(g VS)^(-1)were obtained increased by 45% and 41%respectively,compared with untreated wheat straw.Pretreated wheat straw digestion also yielded a digestate with higher fertilizer values potassium(138%),calcium(22%)and magnesium(16%).These results show that TS,VS and LCH can be effectively removed from wheat straw pretreated with koh,improving biodegradability biomethane production and fertilizer value.

关键词：厌氧消化过程秸秆预处理小麦秸秆 koh 高沼气生产价值肥料