贵州煤制活性炭工艺及其活化过程动力学

设计煤制活性炭的工艺流程,以探索贵州典型煤种制活性炭的可行性。以贵州无烟煤、烟煤及二者混合物为原料,经除灰、炭化后以水蒸汽为活化剂进行活化制活性炭,考察了活化温度、活化时间、水蒸汽流量及水蒸汽压力对活性炭亚甲蓝吸附值的影响,发现所制备活性炭的亚甲蓝吸附值随各因素的变化均存在极大值点,从而确定了适宜的活化条件,无烟煤、烟煤、混合煤所制活性炭的最大亚甲蓝吸附值分别为209、159、223 mg·g~(-1),比表面积分别为1 121.37、908.58、1 342.88 m~2·g~(-1),优于其他活性炭。实验结果也表明:贵州煤制活性炭存在协同效应,混合煤基活性炭具有最好的亚甲蓝吸附性能,且制备条件比单一煤基活性炭更加缓和。基于吸附理论建立了活化过程动力学,回归得到活化过程的速率参数;扫描电子显微镜(SEM)显示,混合煤基活性炭比单一煤基活性炭更加疏松,孔隙更加发达。     

氯霉素在活性炭上的吸附平衡与动力学

为去除水体中残留的氯霉素,采用生物相容性佳的活性炭作吸附剂,测定了25,30,35℃下氯霉素在自制活性炭上的吸附平衡与动力学,并与商用竹炭作对比。结果表明高比表面积活性炭是去除水体中残留氯霉素的高效吸附剂,活性炭的吸附容量随着吸附剂比表面积和孔容的增大而增大,但随温度从25,30到35℃升高而减小,自制高比表面积活性炭的吸附容量达到3种市售活性炭样品吸附容量的10倍以上;Freundlich吸附等温线方程可较好地描述氯霉素在活性炭上的吸附平衡,准二级方程是用来描述氯霉素在活性炭上吸附的合适动力学模型,并通过拟合得到了其动力学参数。随着温度的升高吸附容量逐渐减小。本研究为活性炭对水体中残留氯霉素的吸附处理提供了科学依据。     

水质深度处理用活性炭的选择问题

该文从活性炭吸附容量及吸附速度与粒度的关系，以及吸附容量的条件出发，验证了活性炭的粒度与吸附水中有机物的负相关关系；碘值与亚甲蓝值之和与水处理的动态吸附容量的相关关系，从而指出在评价活性炭的吸附性能时，需要考虑其粒度对有机物去除的影响；要用碘值及亚甲蓝值之和，而不是将它们分开去评价活性炭吸附水中有机物的相关性。     

活性炭电极电容法脱盐性能的研究

研究了活性炭用于电容法脱盐时的电化学性能。用恒压充放电方法研究了操作电压对活性炭电吸附性能的影响,比较了活性炭对不同金属离子的电吸附性能,初步研究了活性炭物性参数与其电吸附性能的关系。结果表明,操作电压与活性炭电吸附容量呈线性关系(0.6~1.2 V),活性炭电极经恒压充放电循环后动态电吸附容量有一定的衰减,这可能与活性炭的表面官能团有关;4种活性炭对质量分数0.1%的碱金属和碱土金属氯化物吸附性能的比较发现,702#活性炭综合性能最好,对于KC l的吸附容量达27.9 mg/g,对NaC l的吸附容量达19.0 mg/g,对于MgC l2的吸附容量达17.0 mg/g;离子特性影响活性炭的电吸附性能;活性炭的比表面积和孔结构是影响活性炭电吸附性能的两个关键因素,比表面积较大、中孔较丰富的活性炭其电吸附性能更好。     

高比表面积煤基活性炭的制备及其吸附性能的研究

以太西无烟煤为原料,KOH为活化剂,采用化学活化法制备高比表面积煤基活性炭,着重考察了碱炭比、活化温度、活化时间对活性炭吸附性能的影响。研究结果表明：当碱炭比为4、活化温度为800℃、活化时间为1h时,可以制得比表面积达3215m^2／g,碘吸附值达2884mg／g,亚甲蓝吸附值达548mg／g的高比表面积煤基活性炭。     

NaOH活化法制备煤基活性炭的研究

以焦作无烟煤为原料,NaOH为活化剂,采用化学活化法制备煤基活性炭,分别考察了碱炭比、活化温度和活化时间等工艺参数对活性炭吸附性能和收率的影响;利用低温N2吸附法对活性炭的比表面积、总孔容及孔径分布进行了表征.结果表明,在碱炭比为4,活化温度为750℃和活化时间为1 h的条件下,可以制得比表面积为2 483 m2/g,总孔容为1.41 cm3/g,碘吸附值为2 530 mg/g,亚甲蓝吸附值为418 mg/g的煤基活性炭.     

氯化锌改性柚皮制备活性炭对亚甲蓝吸附研究

采用氯化锌浸渍柚皮粉末制备活性炭吸附剂,探究了活性炭对染料废水中亚甲蓝的吸附性能。结果表明,在温度25~45℃、pH为2~11时,活性炭均能较好的吸附亚甲蓝;活性炭对亚甲蓝吸附饱和时间为90 min;在亚甲蓝初始含量相同情况下,单位质量活性炭对亚甲蓝吸附量随投加量增加而减少;单位质量活性炭对亚甲蓝的吸附量随溶液初始含量增加而增大;柚子皮活性炭对亚甲蓝的吸附是快速吸附过程,符合准2级动力学方程;温度对活性炭吸附亚甲蓝基本没有影响;活性炭对亚甲蓝的吸附符合Langmuir和Freundlich等温模型,Langmuir模型中最大吸附量达到232.6 mg/g。     

沥青基球状活性炭对肌酐吸附行为研究

考察了具有不同BET比表面积及不同微孔含量的沥青基球状活性炭（PSAC）对肌酐的吸附行为。结果表明，随BET比表面积的增大，PSAC对肌酐的吸附容量及吸附速度明显增大；微孔含量越丰富．其对肌酐的吸附速度及容量越大；吸附动力学研究表明PSAC在水溶液中对肌酐的吸附符合单分子层Langmuir吸附模型。     

净水用活性炭吸附指标相关性试验

近年来,活性炭在水处理应用中发挥着越来越重要的作用,为了更好地对活性炭产品进行规范,用《煤质颗粒活性炭试验方法》(GB/T7702-2008)等一系列的国家标准方法,对不同活性炭样品进行常规吸附指标如碘吸附值、亚甲蓝吸附值、四氯化碳吸附率、比表面积等进行多次检测,得出了大量检测结果.研究发现,不同吸附指标之间存在着一定的相互关系,这对检测工作也具有一定指导意义.     

改性活性炭吸附甲醛的影响因素研究

利用浸渍法制备出以柱状活性炭为基材负载高锰酸钾(KMnO4)的复合型甲醛吸附材料,利用比表面积及孔隙度分析测试仪和场发射扫描电子显微镜观察活性炭改性前后的物理结构变化,搭建单通道滤料性能测试实验台研究高锰酸钾负载率、气体相对湿度、重复负载次数对改性活性炭吸附甲醛的性能影响。结果表明,未负载KMnO4的活性炭对甲醛的吸附性能最差,负载率为5%、10%、20%、24%的改性活性炭比未改性活性炭吸附容量增大1.1、3.5、4.5、5.5倍,最佳负载率为24%;KMnO4负载率10%的改性活性炭在相对湿度为20%、50%的情况下比相对湿度80%时,甲醛吸附容量增大1.5、1.3倍。改性活性炭失活后,重复负载KMnO4 1次仍表现出良好的甲醛吸附性能;但重复负载两次后改性活性炭的甲醛吸附性能下降明显。     

活性炭配炭的吸附性能及其与孔结构的关系

采制11种典型水处理用商品活性炭样品，两两混合进行配炭，对配炭组分及配炭的碘值、亚甲蓝值、丹宁酸值和焦糖脱色率等吸附性能指标及孔结构特征进行了测试和表征。采用加权平均拟合、线性拟合及多项式拟合等方法，研究配炭吸附性能指标与配炭组分吸附性能指标间的量化关系，关联活性炭孔结构与吸附性能指标。结果表明：活性炭配炭的吸附性能指标可由配炭组分的吸附性能指标通过加权平均计算，相对误差<4%，且配炭的孔结构也具备加和性；活性炭碘值、亚甲蓝值、丹宁酸值和焦糖脱色率的大小分别取决于活性炭1.0~2.8nm、1.5~10nm、2.0~50nm和3.0~50nm孔隙的发达程度，与孔容积的线性相关系数介于0.91~0.94。     

Coniferous Wood Sawdust-based Activated Carbons as Adsorbents Obtained with the Use of Microwave Radiation

Activated carbons were prepared by physical and direct activation of sawdust pellets coming from coniferous trees, with the use of microwave radiation. The activated carbons obtained were used as adsorbents for the removal of methylene blue (MB) from aqueous solutions. Liquid-phase adsorption experiments were conducted and the maximum adsorption capacity of each activated carbon sample was determined. The effects of activation procedure as well as adsorption tests parameters i.e., temperature, pH, initial methylene blue concentration, and contact time on the sorption capacity of each activated carbon were investigated. The kinetic models for MB adsorption on the activated carbons were also studied. Better fit to the experimental data was obtained with the Langmuir isotherm than Freundlich one, for all samples.     

磷酸中添加剂对核桃壳活性炭性能的影响

采用磷酸活化法制备核桃壳颗粒活性炭，研究了在磷酸浸渍液中加入不同种类和含量添加剂对活性炭性能的影响。以亚甲基蓝和碘吸附值表征活性炭的吸附性能，并对活性炭的孔结构参数、机械强度和微晶结构进行了测试分析。结果表明：在磷酸中分别添加柠檬酸、柠檬酸钠、硼酸和糖精浸渍处理核桃壳原料，所得活性炭的亚甲基蓝吸附值都得到提高，而碘吸附值降低，说明添加剂促使活性炭中的微孔扩大为中孔。其中，添加0.5%的柠檬酸钠得到最佳的亚甲基蓝和碘吸附值，分别达到236.5和744.1 mg/g。此外，磷酸中添加1%硼酸后得到的活性炭结构中含坚固的炭微晶，起到了增强孔结构的作用，机械强度为85.8%；而添加1%糖精得到的活性炭中的炭微晶几乎全部发生了石墨化转变，生成质软的石墨，使强度下降，机械强度仅为80.1%；添加0.5%柠檬酸钠的活性炭由于发达的孔隙结构且没有炭微晶的加固而强度较低(82.5%)。     

Preparation of activated carbon from paper mill sludge by KOH-activation

The purpose of this study is the preparation of activated carbon using paper mill sludge collected from biological wastewater treatment plant. The char produced from pyrolysis of paper mill sludge was chemically activated with potassium hydroxide. A systematic investigation of the effect of activation agent ratio, activation temperature and time on the properties of the char was carried out in a rotary kiln reactor. The chemically activated carbons were characterized by measuring iodine and methylene blue number and specific surface area. The activated carbon prepared from char of paper mill sludge in this study had maximum iodine and methylene blue number of 726.0 mg/g and 152.0 mg/g, and specific surface area of 1,002.0 m²/g, respectively. The result of estimation on adsorption capacities of metals, the Freundlich isotherms, yields a fairly good fit to the adsorption data, indicating a monolayer adsorption of metals onto activated carbon prepared from char of paper mill sludge using a potassium hydroxide as the activating agents.     

《柠檬酸脱色用颗粒活性炭》标准的研制

对柠檬酸脱色用颗粒活性炭标准研制中各项指标的确定进行了详细的论证。在标准的研制过程中各项指标的确定主要采用了具体实验和采样统计的方法。尤其是对颗粒活性炭脱色力指标进行了大量的实验研究,通过柠檬酸实物脱色的实验研究,证明了采用亚甲基蓝吸附值代替传统的醋酸吸附值来表示柠檬酸脱色用颗粒活性炭的吸附能力是合适的。     

NaOH催化水蒸气活化制煤基活性炭和氢气

在NaOH的催化作用下,通过水蒸气活化法制备了神府煤基活性炭和H2。探讨了NaOH/煤质量比、活化时间、活化温度等工艺条件对活性炭性能和H2产量的影响。结果表明,在活化温度为700℃,NaOH/煤质量比为0.5,单元活化时间为10 min的工艺条件下,可以制得碘值为635 mg/g,亚甲基蓝值为280 mg/g的活性炭,此时H2产量约17.9 mmol/g煤。     

Characterisation of lignite as an industrial adsorbent

An alternative use of the abundant and inexpensive lignite (also known as brown coal) as an industrial adsorbent has been characterised. The adsorptive properties of two Victorian lignite without any pre-treatment were investigated using the cationic methylene blue dye as a model compound in aqueous solutions. Two commercial activated carbon products were also studied for comparison. The adsorption equilibrium of the four adsorbents was better described by the Langmuir isotherm model than the Freundlich model. The adsorption capacities of the two untreated lignite adsorbents, Loy Yang and Yallourn, calculated using Langmuir isotherms were 286 and 370 mg/g, respectively, higher than a coconut shell-based activated carbon (167 mg/g), but lower than a coal-based activated carbon (435 mg/g). Surface area results suggested that larger micropores and mesopores were important for achieving good methylene blue adsorption by the activated carbons. However, FTIR and cation exchange capacity analyses revealed that, for the lignite, chemical interactions between lignite surface functional groups and methylene blue molecules occurred, thereby augmenting its adsorption capacity.     

神府煤KOH催化水蒸气活化制备活性炭和H2

以神府3^-1煤为原料,研究了KOH催化水蒸气活化法制备活性炭,并联产H2的主要影响因素,分析了浸溃比、活化温度、活化时间对活性炭吸附性能和H2产量的影响规律,归纳总结了耦合活化机理。结果表明,当KOH与煤浸渍比为0．5,活化温度为700℃,单元活化时间为10min时,制得的活性炭性能较好,碘值达到851mg／g,亚甲基蓝吸附值达到431mg／g,此时H2产量约33．1mmoL／g。     

化学师范专业活性炭吸附亚甲基蓝综合实验

为提高化学(师范)专业学生的综合实验能力,设计了"活性炭吸附亚甲基蓝"物理化学综合实验.以活性炭为吸附剂,亚甲基蓝( MB) 为吸附质,考察了吸附剂用量、吸附时间、 温度对活性炭去除亚甲基蓝的影响.探讨了水溶液中活性炭固体颗粒吸附阳离子有机染料亚甲基蓝的吸附热力学(吸附等温线类型)、吸附动力学方程和盐酸脱附条件.结果表明,活性炭对亚甲基蓝染料的热力学吸附行为符合 Langmuir 等温吸附方程,其动力学吸附行为符合准一级动力学方程.选择1:1浓盐酸未能有效的将吸附的亚甲基蓝脱附.     

A comparison of adsorption characteristics of various activated carbons

The physico-chemical characteristics of activated carbons obtained from different agricultural by-products by pyrolysis in a stream of water vapor have been investigated. It was established that under the same conditions of treatment the physico-chemical and adsorption characteristics of activated carbons depend on the composition of the initial raw materials. Activated carbon obtained from apricot stones has the best properties. It is characterized by a large specific surface area and micropores volume and high iodine and methylene blue adsorption activity. The activated carbons produced from cherry stones and grape seeds are characterized by predominating meso- and macropores structure. It can be supposed this is related to the larger content of lignin in those materials.