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为了考察常温、无氧下浸渍Na2CO3改性、原料气相对湿度对活性炭吸附硫化氢的促进作用,用动态吸附法分别测试了不同湿度下原活性炭和浸渍活性炭对低浓度硫化氢的吸附,同时考察了温度对该吸附过程的影响。结果表明,吸附平衡数据均符合Freundlich吸附等温方程。与原活性炭相比,浸渍活性炭的孔容和比表面积略有降低,但对硫化氢的吸附能力却显著提高,说明硫化氢与浸渍剂在活性炭表面上发生了化学反应。相对湿度增加,活性炭和浸渍活性炭对H2S的吸附能力均显著增强。温度升高,平衡吸附量均略有下降。 相似文献
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活性炭具有较高的表面积、发达的孔隙结构、优异的表面化学特性以及超强的吸附性能,在化工、医药、食品、冶金等行业有着广阔的应用前景.本文主要介绍了农业废弃物制备活性炭的方法,包括物理活化和化学活化;讨论了活化温度、活化时间以及活化剂浸渍比对制备活性炭的影响,总结了农业废弃物活性炭在去除染料、金属离子和挥发性有机化合物以及气... 相似文献
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关于活性炭的生产原料和方法,我们学院经师生的研究和试验,已成功地找到了一条较好的途径。首先它的原料是用去种后的松果和提取单宁后的松皮松叶,其次是活化方法与其他活性炭的生产活化法有所不同。我们是用高温CO_2来进行活化,这个方法不仅设备简单,成本低,而且活性炭质量是不低于国内先进水平的。其方法如下: 相似文献
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炭在熔融碳酸盐中的直接电化学氧化性能 总被引:1,自引:1,他引:0
研究了活性炭粉在熔融碳酸盐中的直接电化学氧化性能. 通过线性扫描伏安曲线的测试发现, 将炭粉用酸处理, 碳酸盐中的炭含量、炭粒径、反应温度和反应气氛均会对活性炭的电化学氧化性能产生影响. 研究结果表明, 用HCl处理活性炭, 升高反应温度, 适当增加炭含量及炭粒子粒径和通入N2气均会提高活性炭的电化学氧化活性. 经HCl处理的、炭含量为15 g和炭粒径<100 μm的活性炭在850 ℃下、在N2气保护下和电位扫描速率为20 mV/s时的开路电位(OCP)为-1.40 V, 在-0.4 V下的电流密度可达到200 mA/cm2. 相似文献
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活性炭负载磷钨酸催化合成环己酮缩乙二醇 总被引:8,自引:0,他引:8
研究了活性炭负载磷钨酸催化合成环己酮缩乙二醇的反应 ,考察了催化剂负载量、反应时间、酮醇物质的量比、反应温度等因素对缩酮反应的影响 .结果表明 ,活性炭负载磷钨酸是合成缩酮的良好催化剂 ,在优化条件下 ,缩酮产率达 94.8% ,催化剂可重复使用 相似文献
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M. Navarrete A. Gaudry L. Cabrera T. Martínez 《Journal of Radioanalytical and Nuclear Chemistry》2002,251(2):297-298
The retention of iodine traces (ppb) was investigated in small activated carbon filters (50 mg) from solution at a yielding rate exclusively determined by pH. Retention is approximately 100% at pH values of 4–6, while no retention of iodine traces occurs after filtering them through an activated carbon filter from very acidic and basic solutions (pH values of 1 and 11, respectively) with 0% yielding rate. Since activated carbon is a very pure material, this procedure may be an alternative method of the activation analysis of iodine traces in foodstuffs, because the half-life of 128I, formed by (n,g) reaction, is only 25 minutes. It does not allow either the sample to be placed readily in solution or the radioisotope to be separated after irradiation with the purpose of attaining maximal accuracy and sensitivity in this type of analysis. 相似文献
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Adsorption on activated carbon is an efficient method for the removal of toxic dyes. However, since commercially available charcoal is quite expensive, activated carbon obtained from agricultural by‐products may serve as a good replacement. In this study, activated carbon was prepared from pepper peduncle, an agricultural waste product, by microwave activation. The synthesized carbon was characterized by X‐ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy, and thermal gravimetric analysis techniques. It was then used for the adsorption of methylene blue dye from an aqueous solution, which was studied as a function of the dye concentration, contact time, and temperature. The adsorption data were fitted to Freundlich and Langmuir isotherm models. The adsorption kinetics was studied by employing first‐ and second‐order kinetic models, and it was found that the adsorption of methylene blue on the synthesized activated carbon follows a second‐order kinetic model. Effect of temperature on the adsorption process was studied, and the thermodynamic parameters such as activation energy, change in enthalpy, entropy, and free energy of adsorption were calculated on the basis of the absolute theory of reaction rate expressions. About 99.5–91.8% of the dye was removed for an initial dye concentration in the range 20–100 mg/g in 1 h. Thus the synthesized activated carbon was found to be very efficient in adsorbing the dye. 相似文献
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Marek Wojnicki Andrzej Krawontka Konrad Wojtaszek Katarzyna Skibiska Edit Csap Zbigniew Pdzich Agnieszka Podborska Przemysaw Kwolek 《Molecules (Basel, Switzerland)》2021,26(13)
In the paper, the mechanism of the process of the Rh(III) ions adsorption on activated carbon ORGANOSORB 10—AA was investigated. It was shown, that the process is reversible, i.e., stripping of Rh(III) ions from activated carbon to the solution is also possible. This opens the possibility of industrial recovery of Rh (III) ions from highly dilute aqueous solutions. The activation energies for the forward and backward reaction were determined These are equal to c.a. 7 and 0 kJ/mol. respectively. Unfortunately, the efficiency of this process was low. Obtained maximum load of Rh(III) was equal to 1.13 mg per 1 g of activated carbon. 相似文献
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The reaction of allyl carbamates with activated olefins in the presence of Pd(PPh3)4 catalyst in THF proceeded smoothly at room temperature to give the corresponding beta,alpha-bisadducts, beta-amino-alpha-allylated products, in high yields. Not only highly activated olefins containing two cyano groups but also 2-cyano enones underwent facile aza-Michael addition--allylation with various allylic carbamates giving the corresponding products in high yields and with high diastereoselectivities. The stereochemistry of the singly formed product was confirmed with the help of X-ray crystallographic technique. It is an excellent method for creating beta-amino alpha-allyl ketones having two contiguous stereocenters: quaternary carbon adjacent to secondary amine carbon center. 相似文献
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In this paper, adsorption characteristics of methyl mercaptan on virgin activated carbon and copper chloride impregnated activated carbons were studied by using a dynamic adsorption method in a fixed bed. The activated carbons were characterized by nitrogen adsorption, XRD, TGA and solubility tests. The impregnation of copper chloride on the activated carbon significantly enhanced the adsorption capacity of methyl mercaptan, despite a notable decrease in microporosity. It is likely that copper chloride may act as adsorption site for methyl mercaptan. Copper chloride on the activated carbon in a range of 3-20 wt% Cu content was present mostly in the amorphous form of CuCl(2), according to the results of the solubility, XRD and TGA tests. Starting at 10 wt% in Cu loading, the adsorption capacity for methyl mercaptan decreases gradually. It is likely that a decrease in the degree of copper chloride dispersion and an accessibility of small pores may lead to the decrease in the adsorption capacity of the activated carbon for methyl mercaptan. 相似文献
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《印度化学会志》2023,100(1):100864
In this study, the aim was to produce the activated carbon from green coffee for use in liquid phase applications with adding zinc borate which was a boron chemical. Phosporic acid was chosen as the chemical activation material and different reaction parameters (percent of phosporic acid, amount of zinc borate) were tested during the process of chemical activation. The experimental sets were determined by using Taguchi optimization method and optimal conditions were obtained. Taguchi optimization method was preferred to reach optimum process parameters by using time and material in the most beneficial way. The effects of the process parameters (microwave drying time, temperature of carbonization and duration of carbonization) were investigated to determine the optimal sample. The characteristic properties of the obtained activated carbons were determined with Fourier transform infrared spectroscopy (FT-IR), Brunauer-Emmett-Teller surface area analysis (BET), Scanning electron microscopy (SEM) and X-ray diffraction (XRD) analysis. The samples of activated carbon produced were used for determination of the iodine number and the adsorption of heavy metal Cr (VI) ions from solution. Analysis and studies of adsorption showed that activated carbon was produced successfully. The activated carbon was evaluated in liquids phase applications and Langmuir isotherm was found more applicable and experimental data was proper with the second-order kinetic model. 相似文献
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Hua Zhang Sue Li Fenghua Zhang Meixia Wang Xiuchong Lin Huaixiang Li 《Journal of Solid State Electrochemistry》2017,21(3):735-745
Herein, we report a simple method of simultaneous detection of hydroquinone (HQ) and catechol (CC) by cyclic voltammetry (CV) using activated glassy carbon electrodes (GCE). It was found that the two isomers can be completely separated by CV method on cathode polarized GCE (PGCE) after its anodic oxidation. This facile processing method solves the difficulty of electrode surface regenerating which disturb most modified electrodes for the complex composition ease of being contaminated by the analytes in measurement. Morphology and composition of the PGCE were characterized by scanning electron microscope (SEM), Fourier transform infrared (FTIR) spectra, and X-ray photoelectron spectroscopy. In addition, the reaction kinetic of HQ and CC reaction on the PGCE was investigated. It was found that the reaction kinetics of HQ and CC is a surface adsorption-controlled process at low concentration and a diffusion-controlled process at high concentration. 相似文献