共查询到19条相似文献,搜索用时 140 毫秒
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山核桃壳活性炭制备及其吸附苯胺特性 总被引:8,自引:0,他引:8
采用磷酸法制备山核桃壳活性炭,并以磷酸浓度、活化温度和活化时间为因素,亚甲基蓝脱色力、碘吸附值及得率为指标,进行正交设计优化,从热力学角度研究了山核桃壳活性炭对苯胺的吸附行为. 结果表明,磷酸法制备山核桃壳活性炭的优化工艺条件为:磷酸50%(w),活化温度300℃,活化时间45 min. 在此条件下,活性炭得率为53.21%,碘吸附值为804.36 mg/g,亚甲基蓝脱色力为102 mL/g. 在所研究的条件范围内,活性炭对苯胺的吸附能力随温度升高而增大,酸性条件有利于吸附. 吸附是自发吸热的物理吸附过程,遵循Freundlich吸附等温线. 相似文献
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油茶果壳活性炭的制备及其对苯酚的吸附 总被引:2,自引:0,他引:2
以油茶果壳为原料,60%的磷酸溶液为活化剂制备了油茶果壳活性炭,探讨了料液比、活化温度与时间对油茶果壳活性炭吸附苯酚性能的影响。结果表明,在活化温度为600℃,活化时间为90 min,料液比(g∶g)为1∶3时,制备的油茶果壳活性炭对苯酚的吸附效果最好。油茶果壳活性炭对苯酚吸附的最佳条件为:在30℃,0.1 g油茶果壳活性炭对100 mL的500 mg/L苯酚吸附5 h后,吸附量达到了218.0 mg/g。 相似文献
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采用机械力化学技术制备了良好吸附性能的活性炭,采用响应面法优化所制备活性炭的吸附性能。在单因素实验的基础上选取酸屑比、研磨时间、活化温度和磷酸浓度为影响因子,应用BBD(中心组合)进行4因素3水平的试验设计,以亚甲基蓝吸附值作为响应值,进行响应面分析。结果表明,机械力化学法制备磷酸活性炭的较优条件为:酸屑比为2.60,研磨时间为29 min,活化温度为390℃,磷酸浓度为22.5%,活性炭的亚甲基蓝吸附值达21.5 mg/g。 相似文献
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Activated carbon can be produced from a large variety of raw materials, basically by two methods, physical and chemical activation or a combination of both. The adsorption properties of activated carbon vary with the feed materials used and the way of activation. Production cost may be lowered by choosing a cheap raw material and performing a suitable production process. Agricultural and forestry residues, or generally, biomass residue wastes could be used as suitable raw materials for the production of activated carbon. In the present work, different agricultural residues such as hard shells of apricot stones, almond, walnut and hazelnut shells, rice hulls and residues of liquorices were used as precursors. The activation was performed using phosphoric acid under the same conditions. The results showed that at the selected experimental conditions, the type of biomass as well as the final activation temperature, heating rate and impregnation rate of the chemical agent had the greatest influence on the quality of activated carbon. The quality of activated carbon was evaluated in terms of the iodine number reflecting the surface area. According to the results, activated carbon from the hard shells of apricot stones had the best adsorption properties and the largest surface area. 相似文献
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为优化木质活性炭制备的工艺条件,以农林废弃物花生壳为原料,磷酸为主活化剂,硫酸为辅助活化剂,利用响应面模型分析磷酸质量分数、浸渍比(活化剂体积与花生壳质量比)、活化时间、活化温度对活性炭性能的影响。结果表明:通过Box-Behnken试验建立的二次多项式数学模型的P值都小于0.000 1,校正决定系数(R2)分别为0.990 2和0.997 8,变异系数(CV) < 10%,试验的可信度和精确度高,回归方程成立。通过二次回归模型得到磷酸-硫酸活化法制备花生壳基活性炭的最佳工艺条件为花生壳粉末1 g,磷酸质量分数57.7%,浸渍比2:1,活化时间117 min,活化温度550 ℃。在最佳工艺条件下,制备的活性炭亚甲基蓝吸附值为147.2 mg/g,碘吸附值1 022.03 mg/g,实际值与预测值接近,重复性好。利用磷酸-硫酸活化法制备的花生壳基活性炭的内部中小孔较发达,具有较强的吸附能力和脱附能力。 相似文献
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Effects of the heating history of impregnated lignocellulosic material on pore development during phosphoric acid activation 总被引:1,自引:0,他引:1
Activated carbon samples have been prepared by heating China fir (Cunninghamia lanceolata) wood impregnated with phosphoric acid in an effort to elucidate the effect of the heating history of impregnated material on the porous texture of the activated carbon. Analysis of the pore structure of the activated carbon in terms of nitrogen adsorption isotherms showed that both using an intermediate isothermal treatment and slowing the heating rate up to 300 °C favor pore development but have a detrimental effect above 300 °C. Therefore, it is recommended that a two-step heating program is applied for phosphoric acid activation. 相似文献
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以碘吸附值、亚甲基蓝吸附值及活性炭得率为考察指标,选取对糠醛渣活性炭性质影响较大的浸渍比、磷酸质量分数、活化温度、保温时间4个因素进行L16(45)正交试验对磷酸活化法制备糠醛渣活性炭的工艺条件进行优化。由正交试验结果得到磷酸活化的最佳工艺条件为:磷酸质量分数60%,浸渍比2.5:1,活化温度550 ℃,保温1.5 h,此条件下制得的活性炭样品的碘吸附值为839.6 mg/g,亚甲基蓝吸附值为260.3 mg/g,得率为46.8%,比表面积为830.20 m2/g,孔容积为0.502 cm3/g,孔径集中在0.8~2.5 nm,具有丰富的中孔和微孔。 相似文献
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以碱木质素和杉木屑为原料,磷酸为活化剂,制备碱木质素基成型活性炭,考察了碱木质素质量分数、浸渍比、活化温度、活化时间等对活性炭性能的影响。研究结果表明:碱木质素复配杉木屑(碱木质素质量分数50%)后,复配料的表面润湿性显著提高,瞬时水接触角由133.2°(碱木质素)降低至86.6°(复配料);热膨胀系数显著降低,膨胀温度区间的热膨胀系数由2 365μm/(m·℃)(碱木质素)降低至45μm/(m·℃)(复配料)。在最佳工艺条件即碱木质素质量分数50%、浸渍比1.5∶1(纯磷酸与复配料质量比)、活化温度500℃、活化时间90 min下,制备的成型活性炭得率41.76%,碘吸附值1 070 mg/g,亚甲基蓝吸附值255 mg/g,强度90%,比表面积1 646 m2/g,总孔容积为0.795 cm3/g,其中孔径小于5 nm的孔容积占总孔容积的97.2%。 相似文献
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Mohd Zobir Bin Hussein Mohd Basyaruddin Bin Abdul Rahman Asmah HJ Yahaya Taufiq-Yap Yun Hin Nujaimi Ahmad 《Journal of Porous Materials》2001,8(4):327-334
Oil palm trunk is a major lignocellulosic-rich, solid waste material generated from palm-oil upstream industry. The activated carbons prepared from oil palm trunk pretreated with phosphoric acid with the ratio of the acid to the precursor of 0.9, followed by carbonization and activation by carbon dioxide resulted in a high surface area of more than 1800 m2/g with 90% content of micropore surface area. The surface area and the nature of the porosity of the resulting activated carbons were found to be dependent on the amount of the activator used for a fixed quantity of the precursor. Pretreatment of the precursor at low ratio of the phosphoric acid has added advantage, due to the tremendous increase in the apparent surface area of the resulting activated carbon and at the same time enriching its micropore nature. This could result in the conservation of the micropore fraction. On the other hand, using too high a ratio of the phosphoric acid to the precursor did not increase the apparent surface area very much, but instead destroyed the micropore component, and thus increasing the mesopore fraction of the resulting activated carbon. This study also shows that oil palm trunk, a by-product of oil palm industry has a great potential as a raw material for activated carbon production. 相似文献
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以磷矿为原料制备磷酸,通过化学沉淀法脱氟除杂质得到净化的磷酸,再将净化后的磷酸与碳酸钙反应制备饲料级磷酸二氢钙.考察了硫酸质量分数、石灰乳用量、反应时间和反应温度4个因素对磷酸二氢钙产率的影响,得到了制备磷酸二氢钙的最佳工艺条件:硫酸质量分数60%,石灰乳用量7.00 g,反应时间1.5h,反应温度50℃.在此最佳工艺... 相似文献
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黄凤妹 《化学工业与工程技术》2011,32(6):11-13
活性炭生产中用磷酸液进行活化,磷酸液可重复回收利用。由于木屑、炭屑等原材料的影响,用于反复活化浸渍的磷酸液中铁质量分数将从小于10×10-6上升到数百×10-6,甚至更高,不能满足医药、食品等行业对铁离子含量要求较高的活性炭生产之需。采用二甲基肼、15%磷酸液、二硫化碳3种药品于一定条件下反应,制得了螯合络合沉淀剂,于常温下可将回收来的磷酸母液中的铁离子除去,除铁效果显著,达到50×10-6以下,从而使回收的磷酸液满足医药、食品等行业用活性炭的生产要求。该法工艺简单、成本低,且不引入杂质离子,是一种值得推广的应用技术。 相似文献