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用FTIR和N2吸附法对活性炭进行表面分析,通过原子吸收光谱考察了铜在活性炭表面的吸附行为,制备了几种甲醛湿式氧化的催化剂,对比研究了它们在常温常压下对甲醛氧化的催化性能。结果表明,活性炭氧化改性后表面含氧基团增加,对铜和甲醛的吸附性能提高。活性炭表面负载的铜、银、铁对甲醛湿式氧化都有一定的催化能力,其中栽铜活性炭的催化效果最好,载铁活性炭的催化性能优于载银活性炭,催化动力学曲线表明,氧化改性后,载铜活性炭的催化性能进一步提高。 相似文献
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《化工新型材料》2016,(11)
采用H_2O_2-HNO_3混合液对芋叶柄基活性炭进行轻度表面氧化改性,再利用表面负载离子的方法对其表面负载Cu~(2+),制备负载铜芋叶柄基活性炭。以亚甲基蓝脱色率为评价指标,分析2次改性过程对芋叶柄基活性炭吸附性能的影响,利用低温N_2吸附、傅里叶红外光谱(FT-IR)等实验技术,对芋叶柄基活性炭的孔结构与性能进行表征与分析。结果表明,经氧化改性后芋叶柄基活性炭的比表面积及孔径增大,BET比表面积为922.600m2/g,孔容0.068cm3/g,孔径18.471nm,对亚甲基蓝脱色率为74.38%。经2次改性后负载铜芋叶柄基活性炭对亚甲基蓝脱色率达93.44%,吸附能力得到进一步提高。 相似文献
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以N,N-二乙基-1,4-苯二胺(DPD)分光光度法为实验原理,以自配的碘酸钾溶液、磷酸盐溶液和DPD溶液分别作为余氯标准、缓冲液和显色剂,利用分光光度计和便携式余氯仪进行饮用水中余氯检测的方法研究。实验比较了两种余氯标准液和两种便携式余氯仪的测试效果,并对在测试中的主要影响因素进行讨论。结果表明:该方法测定快速、结果准确,且市场粉包显色试剂与国标方法的试剂显色效果一致,基本可满足饮用水中余氯现场快速测定。 相似文献
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分析了水中游离氯及总余氯测定方法的现状,从余氯测定仪校准规范的检测对象、量值溯源、方法原理等方面进行了分析探讨,对实际操作中曲线标定、干扰物消除和方法优化提出建议,对计量检定机构对余氯分析仪开展校准工作有一定的指导意义。 相似文献
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分别采用Cu(NO3)2、H2O2和KMnO4对椰壳活性炭进行改性,研究了活性炭微观结构、表面化学性质变化,及其对SO2、NOx等酸性腐蚀性气氛的吸附性能。结果表明,Cu(NO3)2改性活性炭比表面积显著降低,平均孔径有所下降,Cu(NO3)2微晶分布于活性炭表面及微观孔道内,表面以碳、铜、氧和氮元素为主。H2O2改性活性炭比表面积有所增加,平均孔径减小,H2O2与活性炭表层反应后起到刻蚀效应,引入丰富的微纳孔道结构,使其表面含氧官能团增加,氧元素含量提升。KMnO4改性活性炭比表面积和平均孔径略微降低,KMnO4与活性炭表层反应后含氧官能团增加,反应产物附着于活性炭表面,改变其微观结构。三种方式改性的活性炭对SO 相似文献
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采用静电层层自组装技术和溶胶-凝胶法将不同层数、不同含量的纳米二氧化锆(ZrO2)粒子组装于活性炭表面,得到一种新型的复合材料。用比表面测定(N2-BET)、X射线荧光光谱(EDXRF)等对其进行了表征。系统地研究了纳米ZrO2改性的活性炭对水中2,4-二硝基酚的吸附性能。结果表明,改性后活性炭对2,4-二硝基酚的吸附符合Freundlich模型,吸附过程主要受分配作用控制,吸附容量比改性前提高了25%,而接触时间和初始浓度对吸附效果具有显著影响,并且酸性条件有利于吸附的进行。 相似文献
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碘化钾-淀粉试纸法测水中余氯 总被引:1,自引:0,他引:1
基于余氯对碘化钾的氧化作用和碘淀粉的显色反应,本文提出了测定余氯的碘化钾-淀粉试纸法。研究了最佳测试条件,用于估测水中的余氯,获得了满意的结果。估测范围为1~1000mg/l。 相似文献
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采用硝酸对自制的沙柳活性炭纤维进行处理来制备改性吸附材,并与未改性活性炭纤维进行对比,借助红外光谱、扫描电镜等方法分析两者的性能及结构差异。在含铅污水的净化试验中,重点对比分析了水溶液pH值对吸附效果的影响,线性吸附等温线及吸附动力学模型拟合的差异及循环再吸附性能。结果表明:经硝酸改性后活性炭纤维的整体形貌保持不变,其表面含氧官能团及微孔数量增多。随着pH值的增大,改性吸附剂对铅离子的吸附量和吸附速率均大于未改性活性炭,用Langmuir吸附等温线模型和准二级动力学模型可以更好地描述此吸附过程,且改性活性炭纤维具有良好的循环再吸附性能。 相似文献
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Di Natale F Di Natale M Greco R Lancia A Laudante C Musmarra D 《Journal of hazardous materials》2008,160(2-3):428-434
This work studies the reliability of an activated carbon permeable reactive barrier in removing cadmium from a contaminated shallow aquifer. Laboratory tests have been performed to characterize the equilibrium and kinetic adsorption properties of the activated carbon in cadmium-containing aqueous solutions. A 2D numerical model has been used to describe pollutant transport within a groundwater and the pollutant adsorption on the permeable adsorbing barrier (PRB). In particular, it has been considered the case of a permeable adsorbing barrier (PAB) used to protect a river from a Cd(II) contaminated groundwater. Numerical results show that the PAB can achieve a long-term efficiency by preventing river pollution for several months. 相似文献
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The effect of carbon properties and water characteristics on the adsorption of m-LR by activated carbon was evaluated using kinetic and isotherm tests. The results showed that both physical and chemical effects simultaneously affect the adsorption process. The activated carbon with a high ratio of mesopore and macropore volume showed an increased m-LR adsorption capacity. The micropores in carbon offer only a nominal internal surface for adsorption. The adsorption capabilities of different activated carbon generally followed their pH(zpc) values. Activated carbons with higher pH(zpc) values exhibit a neutral or positive charge under typical pH conditions, promoting m-LR adsorption on the carbon surface. The competitive effects of natural organic matter (NOM) on activated carbon were evaluated and showed that caused a reduction in the capacity of carbon for m-LR. Furthermore, when pre-chlorination was preceded by adsorption, then the residual chlorine would react with activated carbon caused a decrease in sorption capacity of m-LR, while that chlorine at normal treatment plant dosages is not effective for degrading m-LR. 相似文献
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Liu P.-T. Tsai C.-T. Chang T.-C. Kin K.-T. Chang P.-L. Chen C.-M. Chen Y.-C. 《Nanotechnology, IEEE Transactions on》2007,6(1):29-34
This paper proposes a novel method to enhance the emission characteristics of carbon nanotubes (CNTs). It is extremely possible for CNTs to adsorb moisture and other contaminants during the fabrication processes, leading to the degraded field emission characteristics. In this work, CNT emitters are activated with commonly used heating process and supercritical carbon dioxide (SCCO2) fluids technology for removing adsorbed residue moisture. Experimental results have demonstrated that the electrical stability and field emission enhancement of CNT emitters are effectively achieved by the SCCO2 fluids treatment compared to the heating process, due to the minimization of residuary moisture in CNTs 相似文献
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测定了数种吸附剂在不同条件下对微量CH3OH和CO2的吸附和再生情况,比较了不同吸附剂对CH3OH和CO2的脱除精度,为工业深度脱除CH3OH和CO2提供了实验依据。 相似文献
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Advanced tertiary treatment of municipal wastewater using raw and modified diatomite 总被引:7,自引:0,他引:7
Advanced technology for more efficient and effective wastewater treatment is always timely needed. The feasibility of using raw and modified diatomite for advanced treatment of secondary sewage effluents (SSE) was investigated in this study. Raw diatomite at a dosing rate of 300 mg/l showed a similar potential as activated carbon for removing most organic pollutants and toxic metals from SSE. Its performance was found poor in removal of arsenic and crop nutrient constituents (e.g. ammoniacal nitrogen and phosphate) and remained unsatisfactory even when the dosing rate increased up to 500 mg/l. Where modified diatomite was in lieu of raw diatomite, the removal efficiency for all target constituents was improved by 20-50%. At the dosing rate of 150 mg/l, modified diatomite enabled the post-treated effluents to satisfy the discharge consents, with the levels of all target constituents below the regulatory limits. Modified diatomite has advantages over raw diatomite in improving removal efficiency and reducing the dosing rate required for satisfactory treatment of SSE. It is concluded that modified diatomite is much more effective and efficient than raw diatomite, as an alternative to activated carbon, for economic treatment of SSE. 相似文献
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添加致孔剂制备树脂基活性炭及电容性能研究 总被引:1,自引:0,他引:1
以碱性条件下合成的热固性酚醛树脂(PF)为原料,聚乙烯醇缩丁醛(PVB)和聚乙烯二醇(PEG)为致孔剂,采用聚合物共混炭化活化法制备双电层电容器用活性炭材料.通过热重(TG)分析探讨了PF,PF与PVB、PEG的共混物在炭化过程中的热解行为.考察了活化温度和活化时间对所得活性炭的收率、BET比表面积、孔径分布和比电容的影响,并进一步探讨了以这种活性炭材料作电极的双电层电容器的电容性能.结果表明,随着活化温度的升高,活化温度对活性炭收率的影响更为显著,所得活性炭的收率下降.聚合物PEG较PVB更适合作为成孔剂来控制活性炭的中孔孔径分布.酚醛树脂基活性炭电极比电容在850℃活化1 h为79.2F/g,而聚乙烯二醇/酚醛、聚乙烯醇缩丁醛/酚醛混合树脂基活性炭电极比电容则分别高达130.5和145.6F/g. 相似文献
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目的 制备武器装备贮存微环境用单组分的二氧化硫吸附材料。方法 采用双氧水对椰壳活性炭进行表面改性,研究改性活性炭孔隙结构、表面化学性质的变化及其对二氧化硫吸附性能的影响。结果 活性炭存在微孔和中孔,改性后活性炭比表面积略有增加,平均孔径减小。双氧水与活性炭反应起到刻蚀作用,在活性炭表面产生了纳米尺度的网孔结构,降低了活性炭表面碳微晶有序程度,同时双氧水与活性炭反应时起到了氧化作用,提升了活性炭表面氧元素和含氧官能团含量。体积分数为20%的双氧水改性活性炭的吸附容量最高,达到154.15 mg/g,约为改性前的5倍。结论 双氧水对活性炭经表面改性后,产生了纳米尺度的孔隙,并提升了活性炭表面含氧官能团,在两者协同作用下显著提升活性炭对SO2吸附性能,具有良好的装备应用前景。 相似文献
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Removal of lead(II) by adsorption using treated granular activated carbon: batch and column studies 总被引:3,自引:0,他引:3
In the present study, a deeper understanding of adsorption behavior of Pb(II) from aqueous systems onto activated carbon and treated activated carbon has been attempted via static and column mode studies under various conditions. It probes mainly two adsorbents that is, activated carbon (AC) and modified activated carbon (AC-S). Characterization of both the adsorbents was one of the key focal areas of the present study. This has shown a clear change or demarcation in the various physical and chemical properties of the modified adsorbent from its precursor activated carbon. Both the adsorbents are subjected to static mode adsorption studies and then after a comparison based on isotherm analysis; more efficient adsorbent is screened for column mode adsorption studies. The lead removal increased for sample of treated carbon. The extent of Pb(II) removal was found to be higher in the treated activated carbon. The aim of carrying out the continuous-flow studies was to assess the effect of various process variables, viz., of bed height, hydraulic loading rate and initial feed concentration on breakthrough time and adsorption capacity. This has helped in ascertaining the practical applicability of the adsorbent. Breakthrough curves were plotted for the adsorption of lead on the adsorbent using continuous-flow column operation by varying different operating parameters like hydraulic loading rate (3.0-10.5 m3/(hm2)), bed height (0.3-0.5 m) and feed concentrations (2.0-6.0 mg/l). At the end, an attempt has also been made to model the data generated from column studies using the empirical relationship based on Bohart-Adams model. This model has provided an objective framework to the subjective interpretation of the adsorption system and the model constant obtained here can be used to achieve the ultimate objective of our study that is, up scaling and designing of adsorption process at the pilot plant scale level. AC-S column regeneration using 0.5 and 1.0M concentration of HNO3 has been investigated. It has shown a regeneration efficiency of 52.0% with 0.5 M HNO3. 相似文献