活化条件对煤质活性炭比表面积、孔容的影响

我国煤的储存量大、开发制备煤质活性炭是煤炭利用的有效途径之一.本文讨论了同时使用水蒸汽、二氧化碳对煤进行活化时,各因素对活性炭比表面积、孔容的影响,以及比表面积与孔容之间相互的关系.在实验中制备出比表面积为1211.85 m2·g-1的煤质活性炭,为丰富煤炭资源的充分利用寻求方案.     

活化条件对沥青基球状活性炭结构与吸附性能的影响

研究了不同活化条件对沥青基球状活性炭表面物理结构的影响,并初步探索了其作为医学吸附材料对维生素B12及肌酸酐的吸附性能。结果表明：改变活化条件,可在一定范围内控制沥青基球状活性炭的孔径;在实验条件下,沥青基球状活性炭对维生素B12及肌酸酐的吸附率分别达到80％及96％。     

陶瓷基活性炭活化条件对其性能影响

以酚醛树脂为原料,泡沫陶瓷为载体,经过浸渍、固化、炭化后,采用一种复合的活化方法-KOH浸渍加水蒸气括化的复合活化法,制备表薤积较大的酚醛树脂基活性炭。并采用正交试验法考察制备工艺中了活化温度、滔化时间下对所制得得酚醛基活性炭烧失率、碘吸附值、比表面积及其孔结构的影响。结果表明,在活化温度850℃,活化时间80min条件下,可制得比表面积1197m^2/g,中空容0．369cm^3／g,孔径2．57nm的酚醛树脂基活性炭。     

煤质活性炭与椰壳活性炭对漂白废水的吸附性能研究

通过静态吸附实验与动态吸附实验,研究了煤质活性炭与椰壳活性炭对漂白废水的吸附性能。结果表明,在静态吸附条件下,当活性炭用量为6g·L~(-1)、吸附时间为180min、吸附温度为40℃时,煤质活性炭与椰壳活性炭对漂白废水的COD去除率分别为57.89%、60.24%;2种活性炭对漂白废水的吸附动力学均符合Lagergren准二级动力学模型;在动态吸附条件下,各因素对煤质活性炭吸附性能的影响大小为:漂白废水流速吸附时间吸附柱柱高,各因素对椰壳活性炭吸附性能的影响大小为:吸附时间吸附柱柱高漂白废水流速。     

成型工艺条件对活性炭甲烷吸附性能的影响

以ＫＯＨ活化的粉状高比表面积活性炭为原料,羰酸甲基纤维素为粘结剂,制得了一系列高比表面积成型活性性炭,考察了成型压力、粘结剂添加比例及热处理等重要成型工艺条件对型炭甲烷吸附性能的影响。     

油茶壳活性炭活化工艺条件对产品性能的影响

以油茶壳为原料,对未酸洗、酸洗和酸洗+碳酸钾处理后制得的活性炭的性能进行比较。讨论了炭化温度和保温时间对活性炭产品得率、亚甲基蓝吸附值和碘吸附值的影响。研究结果表明,随着炭化温度的升高,未酸洗和酸洗+碳酸钾产品的吸附性能呈不断下降的趋势;酸洗产品的吸附性能随着炭化温度的升高呈不断上升的趋势;800 ℃ 时,未酸洗和酸洗+碳酸钾产品的吸附性能比酸洗的高;随着保温时间的延长,3种产品的吸附性能均呈不断上升的趋势。     

活化条件对活性炭微球结构与性能的影响

以煤焦油系中间相沥青微球为原料,KOH为活化剂,在不同活化条件下制备活性炭微球。考察了不同活化对活性炭微球结构和性能的影响。研究表明：随着KOH配比的增加,活性炭微球的微孔孔容变化较小,中孔孔容和总孔孔容分别增加到最大值后下降,比表面积增大到最大值后有轻微的降低。活化恒温时间对活性炭微球的活化收率和苯吸附值影响较小;而随着活化湿度的升高,活性炭微球总孔容和中孔孔容增大,比表面积先升高后降低。活性炭微球的苯吸附值随着总孔容的增大而增大。     

煤质活性炭对苯酚吸附动力学研究

通过静态吸附实验研究了煤质活性炭对苯酚的吸附特性,并用两种动力学模型对实验数据进行了拟合。结果表明,准二级动力学模型能精确描述苯酚在煤质活性炭上的吸附动力学行为;颗粒内扩散模型拟合表明内扩散过程为该吸附过程的主要控制步骤,但不是唯一控制步骤,吸附同时还受外扩散过程影响。     

煤质成型活性炭的制备及其吸附性能研究

以神木烟煤为原料,煤沥青为黏结剂,在较低浸渍比下采用KOH和ZnCl_2活化法制备成型活性炭,利用低温(77 K)N_2吸附法对活性炭的比表面积及孔结构参数进行表征,考察浸渍比对活性炭孔结构的影响及其液相吸附性能,并对比分析两种化学活化法所制活性炭结构与性能的差异.结果表明,在相同浸渍比下,KOH活化法所制成型活性炭的比表面积、总孔容及碘吸附值均高于ZnCl_2活化法.当浸渍比为1.0时,采用KOH活化法可制备出表面积为811 m~2/g,总孔容为0.513 cm~3/g,中孔比例为23.6%,碘吸附值为1 125 mg/g的成型活性炭;采用ZnCl_2活化法可制备出表面积为472 m~2/g,总孔容为0.301 cm~3/g,中孔比例为30.6%,碘吸附值为527 mg/g的成型活性炭.两种活化法所制成型活性炭的孔径主要分布在1.2 nm~2.0 nm的微孔和3.6 nm~4.5 nm的中孔范围内.     

吸附条件对香蕉叶活性炭吸附效果的影响

以KOH为活化剂对香蕉叶进行炭化活化,制备了具有高吸附性能的活性炭。探讨了初始质量浓度、时间、吸附剂用量、pH值、温度对吸附率的影响,并比较了未活化炭化的香蕉叶粉末及香蕉叶活性炭的吸附效果。结果表明,在亚甲基蓝溶液的体积为100mL,亚甲基蓝的初始浓度为200 mg·~(L-1),吸附时间为2h,香蕉叶活性炭的用量为0.05g,pH值为6.86,温度25℃的条件下,香蕉叶活性炭对亚甲基蓝的吸附率可达99.22%。通过与未炭化活化的香蕉叶的比较可知,香蕉叶经炭化活化后,对亚甲基蓝的吸附率可提高40.72%。     

Diuron Multilayer Adsorption on Activated Carbon from CO2 Activation of Grape Seeds

Granular activated carbons were obtained from grape seeds by pyrolysis at 600°C and subsequent physical activation with CO₂ (750–900°C, 1–3 h, 25–74% burn-off). The carbon and ash content increased during the activation, reaching values of 79.0% and 11.4%, respectively. Essentially microporous materials with BET surface areas between 380 and 714 m²/g were obtained. The performance of the activated carbon in the adsorption of diuron in aqueous phase was studied within the 15–45°C temperature range. Equilibrium data showed that the maximum uptake increased with temperature from 120 to 470 µmol/g, also evidencing some dependence of the adsorption mechanism on temperature. Data were fitted to five isotherm models [Langmuir, Freundlich, Dubinin–Radushkevich, BET, and GAB (Guggenheim, Anderson, and de Boer)]. Kinetic data were analyzed using first- and second-order rate equations and intraparticle diffusion model. The second-order rate constant values obtained (2.8–13.5 × 10^?3 g/µmol min) showed that the hollow core morphology of the material favors the adsorption kinetics.     

Preparation and Phosphine Adsorption of Activated Carbon Prepared from Walnut Shells by KOH Chemical Activation

Walnut-shell activated carbons (WSACs) with high surface area and predominant micropore development were prepared by KOH chemical activation. The effects of carbonization temperature, activation temperature, and ratio of KOH to chars on the pore development of WSACs and PH₃ adsorption performance of the modified walnut-shell activated carbons (MWSACs) were studied. Criteria for determining the optimum preparation conditions were pore development of WSACs and PH₃ breakthrough adsorption capacity of MWSAC adsorbents. The result shows that the optimum preparation conditions are a carbonization temperature of 700°C, an activation temperature of 700°C, and a mass ratio of 3. The BET surface area and the micropore volume of the optimal WASC are 1636m²/g and 0.641cm³/g, respectively. The micropore volume percentage of WSAC plays an important role in PH₃ adsorption when there is a slight difference in BET surface areas. High-surface-area WSACs with predominant micropores are suitable for PH₃ adsorption removal. The MWSAC adsorbent owns the biggest PH₃ breakthrough adsorption capacity (284.12mg/g) due to the biggest specific surface area, total pore volume, and micropore volume percentage. The MWSAC adsorbent will be a potential adsorbent for PH₃ adsorption removal from yellow phosphorus tail gas.     

热解活化法制备高吸附性能椰壳活性炭

以椰壳为原料,采用高温直接热解活化法制备高吸附性能活性炭。研究了活化温度、活化时间对活性炭吸附性能的影响。研究结果表明,活化温度为 900 ℃,热解活化时间为 8 h,升温速率为 10 ℃/min,制得碘吸附值为 1 628.54 mg/g,亚甲基蓝吸附值为 375 mg/g 的高吸附性能椰壳活性炭,得率为 9.41 %。氮气吸附实验结果表明,该活性炭比表面积 1 723 m²/g、总孔容积 0.87 cm³/g、微孔容积 0.68 cm³/g、中孔容积0.18 cm³/g、平均孔径 2.03 nm。热解活化制备的椰壳活性炭样品性能优于市售水蒸气法椰壳净水活性炭国家标准。     

竹炭粒径对竹活性炭的吸附性能与孔结构的影响

研究了竹炭粒径对KOH活化法制备的竹活性炭吸附性能和孔结构的影响。结果表明,竹炭粒径0.18~0.27 mm和0.55~0.88 mm时活化得率较高。竹活性炭碘吸附值和亚甲基蓝吸附值都随竹炭粒径的减小而先减小后增大,与活性炭的比表面积BET和总孔容积变化趋势相一致;苯酚吸附值随竹炭粒径的减小而先增大后减小。竹炭粒径对竹活性炭碘吸附值和苯酚吸附值的影响较小,0.11~0.15 mm粒径竹炭制备的活性炭的亚甲基蓝吸附值最大。0.18~0.27 mm和0.55~0.88 mm粒径竹炭制备的活性炭的平均孔径较小,说明0.18~0.88 mm粒径竹炭制备的活性炭的微孔率相对较高,有利于在低分子质量气体吸附方面的应用。因此,竹炭制备高性能活性炭的较佳粒径为0.18~0.88 mm。     

Adsorption of Radon from a Humid Atmosphere on Activated Carbon

Abstract

Temperature and relative humidity can influence the adsorption capacity of radon on activated carbon to a great extent, depending on the physical properties of the carbon. Experiments were carried out to measure the radon uptake by an activated carbon in the presence of water vapor in a specially designed adsorption apparatus. The radon concentrations in the gas and solid phases were measured simultaneously once the adsorption equilibrium and the radioactive equilibrium between the radon daughter products were reached. The experiments in the presence of water vapor were carried out using two approaches. In one case the activated carbon was preequilibrated with water vapor prior to exposing it to radon. In the other case the carbon was exposed to a mixture of water vapor and radon. The uptake capacity for radon decreased substantially when both components were introduced together compared to when carbon was preequilibrated with water.     

不同粒径活性炭吸附性能的研究

粉末活性炭和颗粒活性炭对对硝基苯酚溶液的吸附速率及吸附量的分析比较。     

活性炭对丁酮的吸附动力学研究

研究了2种活性炭（木质活性炭和煤质活性炭）对丁酮的吸附,重点考察了活性炭的吸附时间、吸附温度和丁酮载气流量对丁酮吸附的影响,并用准一级、准二级、Elovich和Bangham 4种动力学模型对活性炭在不同温度条件下对丁酮的吸附行为进行了动力学拟合,确定其动力学吸附模型。实验表明：不同的活性炭对丁酮的吸附过程不同;活性炭对丁酮的吸附是一个吸附和解吸同时存在的过程,当吸附速率和解吸速率相等时,该过程达到吸附平衡;随着吸附温度的升高,活性炭对丁酮的饱和吸附量逐渐降低,说明活性炭对丁酮的吸附过程为放热反应;丁酮载气流量对活性炭吸附丁酮达到饱和的时间以及吸附速率有影响,对AC-1的最终饱和吸附量影响显著,对AC-2的最终饱和吸附量没有显著影响。这2种活性炭吸附丁酮最适宜的吸附温度均为303 K,最佳的载气流量为400 mL/min。在不同温度下对活性炭吸附丁酮的过程进行动力学分析,发现Bangham方程计算得到的相关系数R²大于0.99,因此,活性炭对丁酮的吸附动力学方程符合Bangham动力学方程。     

Low-Temperature Adsorption of Hydrogen on Activated Carbon

Abstract

The adsorption isotherm of pure hydrogen on activated carbon (coconut shell) was determined at — 186[ddot]C over a pressure range of 1 to 772 mm Hg. A McBain balance apparatus with a modified refrigerant thermostat was used.     

物理活化法制备竹活性炭的研究

本研究以可再生的、资源丰富的赣南毛竹为原料,先以N2为炭化介质进行炭化,然后以CO2作为活化介质对炭化产物进行活化,制备出竹材活性炭.综合考察活化温度和时间等对最终产品收率和亚甲基蓝吸附值的影响.通过N2吸附等温线初步分析吸附过程,确定制备工艺并进行优化,并对制备的竹活性炭进行扫描电镜和透射电镜的结构表征.     

活性炭种类对十二烷基硫酸钠吸附容量的影响

利用亚甲蓝分光光度分析法测定典型市售煤基和木质活性炭对溶液中十二烷基硫酸钠(SDS)的液相吸附等温线,确定活性炭对SDS的吸附容量;采用气体吸附仪表征活性炭的孔结构和比表面积,检测了活性炭样品的碘值及亚甲蓝值;最后关联活性炭吸附性能指标、比表面积与SDS吸附容量之间的关系.结果表明:以长焰煤、无烟煤、褐煤及椰壳为原料制...