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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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《应用化工》2022,(10):2699-2705
探究改性活性炭对模拟的阳离子染料印染废水亚甲基蓝/Cd(2+)混合溶液的吸附效果及其吸附机理。结果表明,改性活性炭对亚甲基蓝/Cd(2+)混合溶液的吸附效果及其吸附机理。结果表明,改性活性炭对亚甲基蓝/Cd(2+)混合溶液的吸附过程中,亚甲基蓝和Cd(2+)混合溶液的吸附过程中,亚甲基蓝和Cd(2+)存在竞争吸附与静电排斥作用,造成改性活性炭对Cd(2+)存在竞争吸附与静电排斥作用,造成改性活性炭对Cd(2+)的吸附性能降低。改性活性炭对模拟的阳离子染料溶液中两种污染物的吸附符合Langmuir模型,吸附动力学属于准二级动力学模型。对亚甲基蓝和Cd(2+)的吸附性能降低。改性活性炭对模拟的阳离子染料溶液中两种污染物的吸附符合Langmuir模型,吸附动力学属于准二级动力学模型。对亚甲基蓝和Cd(2+)的吸附分别为物理吸附和物理与化学吸附共同作用的单分子层吸附。 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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为了探索磁性木质素基活性炭对亚甲基蓝的吸附性能和机制,采用化学共沉淀法制备木质素基磁性活性炭,考察了该磁性活性炭对亚甲基蓝的吸附性能。结果表明:该活性炭吸附亚甲基蓝的过程符合Langmuir吸附等温模型,吸附动力学符合用Elovich模型。磁性木质素基活性炭吸附亚甲基蓝是化学吸附为主的单分子层吸热过程。 相似文献
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凹凸棒石吸附水溶性染料的热力学研究 总被引:29,自引:5,他引:24
通过静态吸附实验,研究凹凸棒石对水溶液中阳离子桃红FG、亚甲基蓝和直接耐酸大红4BS的吸附热力学特性,测定了298~328K范围内的吸附等温线。结果表明:在水溶液中3种染料在凹凸棒石上的吸附均符合Langmuir等温吸附方程。凹凸棒石对水溶液中的阳离子桃红FG和亚甲基蓝的吸附是一个吸热过程,而对直接耐酸大红4BS的吸附是放热过程。根据热力学函数关系计算出阳离子桃红FG、亚甲基蓝和直接耐酸大红4BS在凹凸棒石上的吸附焓变分别为0.49,0.26kJ/mol和-19.68kJ/mol。吸附Gibbs自由能变在-27.48~-31.21kJ/mol之间,表明凹凸棒石对3种水溶性染料的吸附是一自发的过程。凹凸棒石吸附3种水溶性染料均是熵增过程。 相似文献
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用盐酸和焙烧处理的方法对坡缕石黏土进行了改性,制备了酸处理坡缕石黏土和热处理坡缕石黏土,用XRD和TEM对不同方法处理的坡缕石黏土进行了结构和形貌表征,并使用黏土对木质素磺酸盐废水进行了吸附研究。结果表明,在盐酸浓度为1.0 mol/L,60~70℃,改性处理6 h条件下制得的吸附剂相对于原土及热处理的坡缕石黏土吸附效果最好,动力学研究表明吸附过程符合准二级动力学模型,吸附等温线符合Langmuir吸附模型,其平衡吸附量可达到343.99 mg/g。实验证明该吸附过程是一个放热过程。 相似文献
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Equilibrium modeling for the adsorption of methylene blue from aqueous solutions on activated clay minerals 总被引:1,自引:0,他引:1
This work reports the application of an activated clay mineral as adsorbent for the removal of a basic dye, methylene blue (MB), from aqueous solutions. The thermal treatment at 300 °C for 2 h and the acid activation with nitric acid of 0.5 mol/dm3 under reflux conditions improve the adsorption capacity of the raw clay mineral. A maximum of 500 mg/g of MB at equilibrium is achieved. Equilibrium data are mathematically modelled using the Freundlich, Langmuir and Toth isotherm adsorption models. 相似文献
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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. 相似文献
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Baobab fruit shell (BFS), a renewable bio-waste from Malawian baobab tree was used as a precursor for the production of a low-cost activated carbon to remove methylene blue (MB) from aqueous solution. Parameters such as contact time, initial methylene blue concentration, adsorbent dose and temperature were studied. The adsorption process can be well described by both Langmuir isotherm and the pseudo-second-order kinetics. The maximum monolayer adsorption capacity of MB dye was ca. 334.45 mg/g. The negative value of the Gibb’s free energy and positive value of adsorption enthalpy showed the spontaneous nature and endothermic nature of the adsorption process, respectively. 相似文献
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《精细化工》2023,40(1)
木焦油是木质生物质材料的高温裂解产物。以木焦油为碳源,以甲醛化处理后的木焦油为前体,通过碳化-活化制备木焦油基活性碳材料。并以制备的木焦油基活性碳为吸附剂,研究了其对模拟水体中亚甲基蓝的吸附性能。结果表明,以木焦油为前驱体经高温碳化活化制备的多孔活性碳,比表面积可达1373Sm2?g-1,表面含有丰富的含氧官能团。木焦油基活性碳对亚甲基蓝具有良好的吸附性能,准二级动力学模型能更准确的描述木焦油基活性碳吸附亚甲基蓝的动力学过程。吸附等温线更符合Langmuir等温吸附模型,木焦油基活性碳对亚甲基蓝的最大吸附容量可达559 mg?g-1。热力学分析表明亚甲基蓝在木焦油基活性碳上的吸附是放热和自发的。利用木焦油制备的活性碳材料对亚甲基蓝具有较高的吸附容量,是一种具有潜在应用前景的吸附材料。 相似文献
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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. 相似文献
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Erdem Yavuz Gülay Bayramoğlu Mehmet Yakup Arica Bahire Filiz Senkal 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2011,86(5):699-705
BACKGROUND: A core‐shell type carboxylic acid modified resin was prepared and dye sorption characteristics of the resin were investigated. The resulting grafted resin material has been shown to be an efficient sorbent for removal of basic dyes from water as a result of the carboxylic acid group's affinity towards basic dye molecules. RESULTS: The resin was characterized using Fourier transform infrared spectroscopy (FT‐IR) and titrimetric methods. The basic dyes (methylene blue and crystal violet) were removed by contacting the swollen resin with aqueous dye solutions at room temperature. The adsorption capacities of resin were determined by colorimetric analysis of the residual dye content in the adsorption medium, which gave capacities for methylene blue and crystal violet of 300 and 250 mg g?1 resin, respectively. The prepared resin is also able to remove basic dyes completely from dilute aqueous dye solutions. Batch kinetic sorption experiments determined that a pseudo‐second‐order rate kinetic model was applicable. CONCLUSION: Flexibility of the polymer side chains is expected to provide pseudo‐homogeneous reaction conditions and easy accessibility of the functional groups involved. The adsorbents are expected to have the advantage of mobility of the grafted chains in the removal of basic dyes from aqueous mixtures. The resin has potential as an adsorbent for removal of basic dyes for use over a wide pH range. Copyright © 2011 Society of Chemical Industry 相似文献
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《Applied Clay Science》1999,14(1-3):69-82
In this work, a pharmaceutical preformulation study of four Spanish clays (two sepiolites, one palygorskite and one bentonite) is presented, comparing the results obtained with those of three mineral products currently used in pharmaceutical technology. The results showed that the mineralogical and chemical purity of these clays is similar and even higher than that of the three commercial products. The microorganism content is inside the range required for non-sterile pharmaceutical forms. We also determined two parameters concerning the clays' suitability for use in tablet manufacture (colour and water content) and one indicating appropriateness as an antidiarrheic product (adsorption capacity of methylene blue). The clays are yellowish white in colour, although correction does not seem necessary; water content varies according to the structure of the clay and storage conditions. Adsorption capacity of methylene blue is affected by the amount of hydration water present, dehydration temperature and the type of interchangeable cation found in the clay. 相似文献