微波热裂解-KOH活化制备杏壳活性炭及其对甲基橙的吸附性能

以陇东地区生物质废弃物杏壳为原料,采用微波热裂解-KOH活化联合法制备活性炭,研究了微波功率和时间,活化过程中KOH溶液的浓度、用量、浸渍时间、加热活化温度和时间对活性炭吸附性能的影响;以甲基橙为染料模拟印染废水,研究了甲基橙初始浓度、振荡吸附时间和活性炭用量对吸附效果的影响。结果表明:微波功率800W,热裂解30min,生物炭的收率为56%;KOH溶液的浓度为25%,碱/炭为2.5∶1,活化温度800℃,加热活化1.5h,所制备活性炭的碘吸附值为1332mg/g,比表面积为1223m2/g,总孔体积为0.68cm3/g,活性炭的得率为32.7%;甲基橙浓度为250mg/g,振荡吸附240min,活性炭用量为每100mL甲基橙溶液0.15g时,甲基橙去除率高达99.78%;吸附过程符合准二级动力学方程。     

微波加热碳酸钾法制备烟杆基高比表面积活性炭

以烟杆炭化料为原料,采用微波加热碳酸钾活化法制备了高比表面积活性炭.研究了微波加热时间和碱炭比对活性炭的得率和吸附性能的影响,得到了优化工艺条件,所得活性炭产品的碘吸附值为1834mg/g,亚甲基兰吸附值为517.5mg/g,得率为16.65%.产品的吸附性能超过了双电层电容器专用活性炭(LY/T 1617-2004)标准的要求,同常规加热相比,活化时间缩短了78.26% .同时测定了该活性炭的氮吸附等温线,通过非定域化密度函数理论表征了活性炭的孔结构.该高比表面积活性炭的比表面积为2557m2/g,总孔体积为1.6470ml/g.     

氯化锌活化法制备木质活性炭研究

采用氯化锌活化法在不同操作条件下制备木质活性炭产品,通过实验测定相应的活性炭得率及活性炭的碘值、亚甲基蓝吸附值和苯酚吸附值.分析研究了氯化锌活化法制备活性炭工艺过程中各种操作参数如浸渍比、活化时间和活化温度对活性炭的得率、活性炭碘值、亚甲基蓝吸附值和苯酚吸附值的影响.实验结果表明,浸渍比是氯化锌活化法制备活性炭的最重要的影响因素.综合考虑活性炭的得率和吸附性能受活化操作参数的影响规律,探讨了氯化锌活化法制备木质活性炭的最优操作参数.在实验范围内,选择氯化锌活化法制备木质活性炭的浸渍比100%,活化温度500℃左右和活化时间60～90min比较适宜.     

兰炭基均匀超微孔活性炭的制备及其表征

以KNO_3为氧化剂,经5%~15%(质量分数)KOH常温浸渍,在N_2-水蒸气混合气氛下进行控制热分解制备均匀超微孔活性炭。试验选用正交试验法,选择活化温度、活化时间、KOH浸渍浓度、浸渍时间等参数为影响因素,以碘吸附值为考察指标,得到最佳水平组合,活化温度900℃,活化时间1h,KOH浓度15%,浸渍时间24h。对活性炭表征结果如下:最佳样品碘吸附值达840 mg/g。BET比表面积为725cm~2/g,中值孔径为0.489nm,其中微孔容积占总孔容的70.8%,氢气最大吸附量达76.85cm3/g。该样品以超微孔为主,超微孔孔径主要分布在0.45~0.52nm之间,孔分布比较集中,可用于混合气体分离。     

ZnCl2活化茄子秸秆制备活性炭及表征

以茄子秸秆为原料、ZnCl2为活化剂制备活性炭。通过正交实验方法确定了制备活性炭的最佳工艺条件,采用低温氮气吸附、BET、Langmuir和BJH理论对其孔结构进行了表征,利用红外光谱分析样品的表面官能团,扫描电镜观察表面形貌。结果表明以茄杆活性炭的最佳工艺条件:浸渍比为2,浸渍时间为8h,活化温度为550℃,活化时间为60min,所得的活性炭的碘吸附值为1270.06mg/g,亚甲基蓝吸附值为17.4mL/g;BET和Langmuir比表面积分别为1649.615和1851.649m2/g,吸附总孔容为0.488cm3/g,吸附平均孔径为2.241nm。     

H3PO4活化紫茎泽兰制备活性炭及其性能研究

以紫茎泽兰为原料,采用H_3PO_4活化的方式在管式电阻炉中加热制备紫茎泽兰基活性炭。主要考察以N2作保护气体时活化温度、保温时间以及H_3PO_4浓度(质量分数)对活性炭吸附性能及得率的影响。获得优化实验条件:活化温度400℃、保温时间60 min、H_3PO_4浓度50%,并测得相应的亚甲基蓝吸附值为210 mg/g、得率为59.70%,其中亚甲基蓝吸附值为国家标准GB/T 13803.2-1999活性炭一级品的1.6倍。优化实验条件下活性炭的BET比表面积、总孔体积、平均孔径分别为1346m2/g、0.83cm3/g、2.45nm,同时用傅里叶变换红外光谱(FT-IR)和扫描电镜(SEM)对活性炭进行分析表征。实验结果表明紫茎泽兰是一种制备活性炭的良好前驱体材料。     

超高比表面积活性炭的制备与表征

以无患子残渣为原料,KOH与K2CO3作为活化剂,采用微波炭化和活化两步法制备超高比表面积活性炭,通过正交实验优化活性炭的制备工艺,探讨了碱炭比、活化温度和活化时间对活性炭吸附亚甲基蓝吸附值的影响。利用N2吸脱附实验、XRD、FT-IR等实验技术,对制备的活性炭结构与性能进行了表征。结果表明,在碱炭质量比为4∶1、活化温度800℃、活化时间30 min的条件下,所制备的活性炭对亚甲基蓝吸附值为595 mg/g,BET比表面积为3 479 m2/g,吸附累积总孔容达1.8262 cm3/g,平均孔径为2.0997 nm。     

NaOH活化法制备高比表面积稻壳活性炭

以农业废弃物稻壳为原料,NaOH为活化剂,制备了中孔发达的高比表面活性炭,研究了碱炭比、活化温度对样品碘吸附值和亚甲基蓝吸附值的影响;采用SEM、TEM表征了活性炭的形貌,通过BET法计算了活性炭的比表面积,BJH方程计算出活性炭的孔径分布.结果表明,在碱炭比为3∶1、活化温度为750℃的工艺条件下制备的稻壳活性炭同时具有较高的碘吸附值和亚甲基蓝吸附值;稻壳活性炭比表面积高达2164m2/g,中孔含量达到63.67%,总孔容达到1.544mL/g.     

KOH活化法制备汉麻秆活性炭及其微孔结构的研究

采用生物质材料制备比表面积大、微孔结构发达的活性炭,对于缓解资源紧缺、拓展活性炭在气相吸附和双电层电容器等方面的应用具有重大意义。以汉麻秆为原料、KOH为活化剂制备活性炭,通过正交试验探讨碱炭比、活化温度、活化时间对活性炭得率和碘吸附值的影响;采用场电镜、孔径分析仪对样品的微孔结构进行分析。结果表明,影响活性炭得率和碘吸附值的最显著因素分别为碱炭比和活化温度,在碱炭比4∶1、活化温度900℃、活化时间为0.5h的条件下,活性炭得率为72%、碘吸附值为2 047mg/g,比表面积为1 924.08m2/g,总孔容为1.01cm3/g,平均孔径为2.1nm;该活性炭的微孔结构发达(微孔率为81.19%),孔径分布较窄,同时存在超微孔和极微孔,且极微孔含量很高。     

超声引入酸浸渍过程对活性炭性能的影响（英文）

在磷酸法制备活性炭的浸渍阶段引入超声,研究超声浸渍对活性炭孔结构、微观形貌、表面官能团、碘值和亚甲基蓝值的影响。结果表明,超声浸渍能够增大活性炭的比表面积、总孔容、微孔孔容、中孔孔容、极微孔孔容、碘值和亚甲基蓝吸附值,但长时间超声浸渍并无必要。最佳超声浸渍条件为:在45 min的总浸渍时间内引入5 min超声浸渍。在该条件下制得的活性炭比表面积达1 504 m~2/g,超过了文献中生物质基磷酸法活性炭的诸多相应值。另外,与静置浸渍相比,超声浸渍使制备最高碘值样品所需的总浸渍时间减少了85%。     

Production of activated carbon from a new precursor molasses by activation with sulphuric acid

Activated carbon has been prepared from molasses, a natural precursor of vegetable origin resulting from the sugar industry in Morocco. The preparation of the activated carbon from the molasses has been carried out by impregnation of the precursor with sulphuric acid, followed by carbonisation at varying conditions (temperature and gas coverage) in order to optimize preparation parameters. The influence of activation conditions was investigated by determination of adsorption capacity of methylene blue and iodine, the BET surface area, and the pore volume of the activated carbon were determined while the micropore volume was determined by the Dubinin-Radushkevich (DR) equation. The activated materials are mainly microporous and reveal the type I isotherm of the Brunauer classification for nitrogen adsorption. The activated carbons properties in this study were found for activation of the mixture (molasses/sulphuric acid) in steam at 750 degrees C. The samples obtained in this condition were highly microporous, with high surface area (> or =1200 m2/g) and the maximum adsorption capacity of methylene blue and iodine were 435 and 1430 mg/g, respectively.     

Activated carbons from sewage sludge and discarded tyres: production and optimization

This is a study about making use of two residual materials such as sludges from a sewage treatment plant and discarded tyres to generate activated carbons and later optimize the production process. H2SO4 and ZnCl2 were used as chemical activating agents. Liquid-phase adsorption tests were made using the produced carbons to retain methylene blue and iodine. The best precursor was sludge activated with ZnCl2. After optimization studies, the best production methodology involved a 1:1 ratio of sludge and ZnCl2, a heating rate of 5 degrees C/min up to 650 degrees C and a residence time of 5 min. The resulting materials adsorbed up to 139.4 mg/g of methylene blue and 1358.5 mg/g of iodine. Nevertheless these carbons may leach Zn while using. To avoid this two treatments were carried out: one consisting of a coating with a polymer and another involving an intensive washing, which was seen to be more efficient.     

水蒸气活化再生扑热息痛用废活性炭的研究

以扑热息痛生产过程中产生的废活性炭为研究对象,采用管式电阻炉的加热方式对其进行再生条件的研究。实验重点考察了在氮气作为保护气体的条件下再生温度、再生时间、水蒸气流量3个因素对再生活性炭亚甲基蓝吸附性能和得率的影响。得到了废活性炭再生的最佳实验条件:再生温度750℃,再生时间20min,水蒸气的流量2.0mL/min。在最佳实验条件下得到的再生活性炭的亚甲基蓝吸附值为184.5mg/g,得率70.56%,在此条件下测得再生活性炭的比表面积为996.8m2/g,总孔体积为0.995mL/g。通过对废活性炭和再生活性炭扫描电镜的分析发现再生后的活性炭孔隙数量增多并且其表面杂质明显减少。     

基于吸附性能的生物质基多孔活性炭制备方案的响应面法优化

以废弃核桃壳作为原料,采用微波加热法制备生物质基多孔活性炭。基于响应面法和数值模拟方法研究活性炭前驱体进行物理活化过程中微波功率、活化时间以及磷酸质量分数对生物质基多孔活性炭吸附性能的影响,对生物质基多孔活性炭制备方案进行优化,并对最优条件下制备的生物质基多孔活性炭进行表征。结果表明,3个因素均对生物质基多孔活性炭的吸附性能有影响,其影响显著性为:微波功率磷酸质量分数活化时间。优化的制备条件为:微波加热法对活性炭前驱体进行物理活化过程中的微波功率为746W、活化时间为11.2min以及磷酸质量分数为85.9%。优化生物质基多孔活性炭的碘吸附值为1074.57mg/g,亚甲基蓝吸附值为294.4mL/g,获得率为52.1%。     

Characterization and use of high surface area activated carbons prepared from cane pith for liquid-phase adsorption

Carbonaceous adsorbents with controllable surface areas were chemically activated with KOH at 780 degrees C from char that had been carbonized from cane pith at 450 degrees C. The pore properties including the BET surface area, pore volume, pore size distribution, and mean pore diameter of these activated carbons were characterized and derived using the t-plot method based on N(2) adsorption isotherms. The activated cane pith carbons, with KOH/char ratios of 2-6, exhibited BET surface areas ranging from 912 to 2299 m(2) g(-1). The scanning electron microscopic (SEM) observations revealed that the surface morphology of honeycombed holes on all activated cane pith carbons was significantly influenced by the KOH/char ratio. The adsorption kinetics and equilibrium isotherms of acid blue 74, methylene blue, basic brown 1, p-nitrophenol, p-chlorophenol, p-cresol, and phenol from water at 30 degrees C on the activated carbons were studied. The adsorption kinetics were suitably described by a simplified kinetic model, the Elovich equation. All adsorption equilibrium isotherms were in agreement with the Langmuir equation, and were used to compare the covered area (S(c)/S(p)) of the activated carbons at different KOH/char ratios. The high-surface-area activated carbons were proven to be promising adsorbents for pollution control and for other applications.     

表面改性对活性炭孔结构及热电转换性能的影响

为探究表面改性对活性炭孔结构及热电转换性能的影响,使用HNO_3和KOH在不同条件下对活性炭进行表面改性,用N2吸附法和XRD图谱表征活性炭改性前后孔结构和石墨化程度的变化。结果表明,改性后活性炭的比表面积和孔容提高,平均孔径减小,并存在石墨晶体结构。干法改性活性炭的比表面积和总孔容由1 077.880m~2/g和0.763cm~3/g分别增加到1 635.268m~2/g和1.128cm~3/g,并且微孔的孔容增加。改性处理可以去除活性炭中的杂质。分别以改性前后活性炭为材料制备固体电极,KCl为电解液,测试活性炭电极的热电转换性能,发现改性后活性炭具有更高的热电转换性能。     

中药渣制备活性炭及其工艺优化

以中药渣为原料,采用真空化学活化法制备活性炭,并以活性炭的亚甲基蓝和碘吸附值为优化指标,选用Doehlert设计安排实验,在合适的范围内,对影响ZnCl2活化法最重要的两个因素活化温度和浸渍比进行了优化。结果表明,在实验条件范围内,对于所有的响应,活化温度的影响均大于浸渍比,且两者对活性炭产率的影响都不大。得到的最优条件为活化温度474℃,浸渍比1.225,在此条件下制得活性炭的亚甲基蓝值和碘值分别为316 mg.g-1和994 mg.g-1,与理论模型计算值非常接近。和普通商品活性炭相比,用该实验方法所制活性炭具有更好的实际吸附效果。     

Preparation of activated carbons from coffee husks utilizing FeCl3 and ZnCl2 as activating agents

Ferric chloride was used as a new activating agent, to obtain activated carbons (AC) from agro industrial waste (coffee husks). This material was compared with two samples from the same raw material: one of them activated by using the classical activating agent, zinc chloride, and the other, activated with a mixture of the two mentioned activating agents in the same mass proportion. The carbonaceous materials obtained after the activation process showed high specific surface areas (BET), with values higher than 900 m(2)g(-1). It is interesting to observe that the activation with FeCl(3) produces smaller pores compared to the activation with ZnCl(2). An important fact to emphasize in the use of FeCl(3) as activating agent is the activation temperature at 280 degrees C, which is clearly below to the temperature commonly employed for chemical or physical activation, as described in the bibliography. All the studied materials showed different behaviors in the adsorption of methylene blue dye and phenol from aqueous solutions.     

Pore structure and adsorption performance of the activated carbons prepared from plum kernels.

According to iodine number, amount of methylene blue adsorption, the BET specific surface area, and the yield, the conditions for preparing activated carbons as adsorbents from plum kernels were optimized. The activation temperature and time tested were in the ranges 750-900 degrees C and 1-4 h, respectively. Adsorption isotherms of two commercial dyes and phenol from water on such activated carbons were measured at 30 degrees C. It was shown that the optimal activation temperature and time depended on the molar mass of the solutes, and all equilibrium isotherms could be fitted by the Langmuir equation. The experimental results indicated that the prepared activated carbons were economically promising for adsorption removal of dyes and phenol, in contrast to other commercial adsorbents.