共查询到19条相似文献,搜索用时 62 毫秒
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通过磷酸改性处理活性炭,考察改性前后活性炭对亚甲基蓝吸附量的变化。关于活性炭对亚甲基蓝吸附行为的描述采用Langmuir和Freundlich吸附等温线模型。进一步研究了活性炭对亚甲基蓝的吸附动力学性质。试验改变因素包括吸附时间、吸附温度、亚甲基蓝溶液体积和活性炭投加量,探究这些因素对亚甲基蓝去除的影响。结果表明:质量分数为60%磷酸改性活性炭在吸附时间30 min、亚甲基蓝溶液体积40 m L、活性炭投加量0. 4 g、温度70℃时对亚甲基蓝的清除率最好。Langmuir等温模型能更好地拟合试验结果。活性炭吸附亚甲基蓝的动力学曲线更符合准二级动力学模型。研究表明磷酸改性的秸秆基活性炭对亚甲基蓝具有较好的吸附效果。 相似文献
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为探索废弃烟秆改性后得到的烟秆碳化材料对亚甲基蓝的吸附性能,研究了pH、烟秆碳化材料投加量、反应时间和亚甲基蓝初始浓度对烟秆碳化材料吸附性能的影响,分析了吸附动力学和热力学以及烟秆碳化材料的形态特征.结果表明,烟秆碳化材料吸附亚甲基蓝的最佳条件为:pH 6,吸附剂投加量2 g/L.对于100~400 mg/L的亚甲基蓝溶液,吸附平衡时间为60~360 min.烟秆碳化材料对亚甲基蓝的吸附符合拟二级动力学模型和Langmuir模型,说明吸附过程是单层吸附,最大吸附量为636.9 mg/g. 相似文献
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以磷钨酸(PW_(12))和劳氏紫(TH)为原料,采用直接沉淀技术制备了(TH)_3PW_(12)复合材料。对所得材料进行了红外光谱的表征,考察了复合材料投加量、吸附时间和亚甲基蓝浓度对吸附效果的影响,并对其吸附动力学和热力学特性进行了探讨。结果表明,亚甲基蓝的去除率随催化剂质量的增加而升高,而平衡吸附量却急剧减小。随亚甲基蓝初始浓度的增加,其去除率呈下降趋势;吸附量随吸附时间先急剧上升,随后变化趋于平缓。复合吸附剂对亚甲基蓝的吸附满足Langmiur等温吸附方程,吸附动力学曲线符合准二级动力学模型。 相似文献
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以煤矸石提铝尾渣制得的介孔硅酸钙为吸附材料,研究了介孔硅酸钙对亚甲基蓝的吸附性能。考察了亚甲基蓝溶液pH、吸附剂添加量、吸附时间和吸附温度等因素对吸附效果的影响。结果表明,介孔硅酸钙对亚甲基蓝表现出良好的吸附性能,在298 K、pH=11、介孔硅酸钙投加量为0.2 g/L、吸附时间为60 min条件下,亚甲基蓝的去除率达87.33%。介孔硅酸钙对亚甲基蓝的吸附过程符合准二级动力学模型和Langmuir 吸附等温线方程,吸附方式为单分子层吸附,饱和吸附量为89.68 mg/g。吸附过程为熵增加的自发过程,升温有利于吸附。吸附焓变ΔH为62.72 kJ/mol,介孔硅酸钙对亚甲基蓝的吸附以化学吸附为主。 相似文献
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Asphaltene adsorption measurements with a well crystallized kaolin, a poorly crystallized kaolin, and a montmorillonite under anhydrous conditions and in the presence of water showed that the adsorption varied depending on the properties of the clay and the amount of water. The presence of presorbed water on the clays reduced asphaltene adsorption. Adsorption experiments made at elevated temperatures did not substantially alter adsorption data. 相似文献
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Heats as well as entropies of water and nitrogen adsorption on hardened cement pastes of various pore structures were computed. Water vapor adsorption is accompanied by a decrease in integral entropy relative to the liquid state, while nitrogen adsorption is accompanied by an increase in integral entropy. The results could be related to the pore structures of the various pastes. For water adsorption, the molecules seem to be oriented in a definite array with more order than the liquid structure, and depending on the pore size, the normal liquid structure is resumed at some distance far from the surface. Nitrogen results could be described in terms of the inaccessibility and exclusion of the molecules from parts of the pore system. 相似文献
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An acid-activated clay (Çanakkale montmorillonite from Turkey) was used to adsorb chlorophyll from hexane solutions. The phenomenon seems to be mainly driven by the interaction of chlorophyll with acid sites. The adsorption of chlorophyll on Brönsted acid sites was indicated by a characteristic infrared band for the -OH group at 3671 cm?1. The variations in the structure of clay mineral and chlorophyll during adsorption have been examined by differential thermal analysis, thermogravimetry and infrared spectroscopy of the activated clay before and after adsorption of chlorophyll. Oxidation of adsorbed chlorophyll was completed at quite a high temperature. 相似文献
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The hydrogen adsorption on basal graphite planes functionalized by hydrogen atoms is studied by molecular modeling and numerical simulation at temperatures of 77 K and 293 K up to high pressure. At 77 K and pressure of 1 MPa, on such an adsorbing surface, the excess hydrogen physisorption is estimated equal to . At 293 K and 30 MPa, the excess physisorption reaches . A comparison between the hydrogen adsorption properties of functionalized graphite basal planes and plain graphite basal planes is presented for materials exhibiting similar porosities. 相似文献
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