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1.
水蒸气活化烟杆制造活性炭及孔结构表征   总被引:3,自引:0,他引:3  
以烟杆为原料,以水蒸气为活化剂,采用正交实验研究了水蒸气流量、活化时间和活化温度对活性炭得率和吸附性能的影响,最佳工艺条件为活化温度900℃,时间为30分钟,水蒸气流量3.09mL/min,在此条件下制得活性炭产品的碘吸附值为946.52mg/g,亚甲基蓝吸附值为21mL/0,1g,得率为32.64%。同时测定了该活性炭的氮吸附等温线,并通过BET、H-K方程、D-A方程和密度函数理论(DFT)表征了活性炭的孔结构。结果表明:该活性炭为微孔孔型,BET比表面积为1044m^2/g,总孔体积为0.5870mL/g,微孔体积占总孔体积的72.03%,中孔占26.92%。大孔占1.05%。  相似文献   

2.
室内甲醛气体是一种常见的室内污染物,对人体有害。近年来,吸附甲醛的研究成为国内外的热点。使用超声波协同负载,在可塑性高的活性炭纤维(ACF)材料上负载铜离子改性用于治理室内甲醛等污染。利用扫描电子显微镜(SEM),光电子能谱(EDS)对载铜ACF进行表征,发现含铜化合物附着在ACF表面。其中的含铜基团对甲醛的吸附起了重要作用。根据吸附材料吸附对比研究,所得的载铜ACF吸附效果优于其他吸附材料,甲醛去除率在80min内可达到0.063mg/g,比未改性活性炭高26%,比活性炭高57.5%,比生物质炭高75%。  相似文献   

3.
化学活化法制备麻疯树果壳活性炭的实验研究   总被引:1,自引:0,他引:1  
以麻疯树果壳为原料,KOH为活化剂,通过化学活化法制备活性炭。考察了反应温度、反应时间和碱炭比(KOH与麻疯树果壳炭化料的质量比)等因素对活化结果的影响,并利用N2吸附和BET等现代分析测试方法来表征活性炭的结构特征。结果表明,化学活化法制备的活性炭吸附剂性能较好,且当活化温度为850℃,活化时间为240min,碱炭比R=4时制得活性炭产品的质量最好;化学活化法制备的活性炭为微孔吸附剂,在最佳条件下得到最大的碘吸附值和比表面积分别为2218.44mg/g和1890m^2/g。  相似文献   

4.
研究了pH值、吸附接触时间、铜离子的初始浓度及活性炭纤维(ACF)的投加量对活性炭纤维吸附Cu2+的影响,并选取了最佳的实验条件。用Langmuir方程和Freundlich方程拟合活性炭纤维对Cu2+吸附等温线,结果表明:活性炭纤维吸附Cu2+更符合Langmuir等温式,其相关系数为0.9995,以单分子层吸附为主。对活性炭纤维改性能明显提高对Cu2+的吸附,其中效果最佳的吸附量从4.8mg/g增加到17.32mg/g,提高了3.6倍。  相似文献   

5.
为高效去除工业废水中的氨氮化合物,采用椰壳活性炭为原材料,通过碱性溶液改性制备高性能吸附剂。通过表面特征分析发现2 mol/L氢氧化钠改性后的椰壳活性炭孔体积和吸附平均孔径最小,比表面积最大;分析不同体系温度对改性活性炭吸附性能的影响,结果表明:温度对于氨氮的吸附效率影响较大,在35℃时的吸附效果最优,利用等温吸附模型Langmuir方程拟合得到计算理论吸附量为38.8 mg/g;改性椰壳活性炭的吸附行为符合准二级动力学模型,进一步表明椰壳活性炭对废水中氨氮化合物的吸附是易于发生的化学吸附过程。由此可见,改性椰壳活性炭作为一种高性能吸附材料,在去除水中的氨氮化合物方面具有良好的应用价值。  相似文献   

6.
为筛选出适合苏州地区深度处理工艺所需的活性炭,对活性炭的吸附性能、生物膜挂膜情况以及出水浑浊度、高锰酸盐指数、TOC、UV254、氨氮、亚硝酸盐氮等水质指标进行了考察。结果表明,GAC3和GAC4活性炭在各项性能方面均优于其他活性炭。从价格上考虑,选取GAC4活性炭作为苏州市该水厂深度处理活性炭。活性炭滤池运行3个月后,对其出水进行了106项全分析,所有水质指标均能达到GB 5749-2006的要求。  相似文献   

7.
常兰  向容瑶  张梅 《四川环境》2020,39(5):119-123
利用食品废弃物柚子果皮为碳源制备活性炭,研究了其对放射性铀元素的吸附效果。考察了pH值、吸附时间、初始浓度等对吸附的影响,并对不同温度下的吸附数据用langmuir方程和Freundlich方程进行了拟合。结果表明,柚子皮活性炭对铀离子的吸附在120min达到平衡,平衡吸附量随着铀离子初始浓度和吸附剂投加量的增大而增大;柚子皮活性炭对铀的吸附能力随温度的升高而增大,langmuir等温吸附模型更适合描述其吸附行为;在318K时,理论最大吸附容量为12.10mg/g。  相似文献   

8.
茄子秸杆活性炭对染料废水的吸附性能研究   总被引:2,自引:0,他引:2  
以茄子秸秆为原料,ZnCl2为活化剂制备粉末状活性炭,主要研究了活性炭对染料废水的吸附性能;以活性红X-3B和酸性蓝RL为模型染料,考察了染料初始浓度、pH值、活性炭投加量和吸附时间等对染料脱色率的影响。结果表明,染料初始浓度和活性炭投加量对染料脱色率影响较大。初始浓度为300mg/L时,活性炭的最佳投加量分别为1g/L和1.4g/L;在最佳工艺条件下,脱色率分别在93%和98%以上,COD去除率分别为94.5%和86.4%,出水水质达到国家一级《纺织染整工业水污染物排放标准》(GB 4287—1992)。  相似文献   

9.
选用牛粪基活性炭进行负载,使用超声波协同浸渍负载铁,得到一种简单快速且成本较低的载铁活性炭制备方法。实验表明,在牛粪活性炭与铁盐在质量比1∶2,30℃下使用超声波浸渍40min为最佳的负载方法。利用扫描电子显微镜(SEM),X射线衍射(XRD),红外光谱法(IR)对优方案的载铁活性炭进行表征,发现含铁化合物均匀的分布在活性炭孔道中,无固定晶型。其中的含铁基团对磷的吸附起了重要作用。根据载铁活性炭吸附研究,所得的载铁活性炭对浓度为25mg/L的模拟含磷溶液去除率最高达96%以上。能较好的符合Freundlich热力学方程与拟二级动力学方程(R20.97),得到的最大吸附浓度达到19.723mg/g,吸附开始2min去除率即可达70%。  相似文献   

10.
以活性炭为载体,负载活性组分金属Co,制备了Co/AC催化剂,采用催化过氧化氢氧化技术(CWPO)处理腈纶废水,考察其催化氧化性能。实验结果表明:将预处理后的20-40目粒状活性炭浸渍于质量浓度为7%Co(NO3)2溶液中,浸渍9h后,经自然晾干,在500℃的条件下焙烧4h得到的Co/AC催化剂催化效果最好。  相似文献   

11.
In this article, the technical feasibility of the use of activated carbon, synthetic resins, and various low-cost natural adsorbents for the removal of phenol and its derivatives from contaminated water has been reviewed. Instead of using commercial activated carbon and synthetic resins, researchers have worked on inexpensive materials such as coal fly ash, sludge, biomass, zeolites, and other adsorbents, which have high adsorption capacity and are locally available. The comparison of their removal performance with that of activated carbon and synthetic resins is presented in this study. From our survey of about 100 papers, low-cost adsorbents have demonstrated outstanding removal capabilities for phenol and its derivatives compared to activated carbons. Adsorbents that stand out for high adsorption capacities are coal-reject, residual coal treated with H3PO4, dried activated sludge, red mud, and cetyltrimethylammonium bromide-modified montmorillonite. Of these synthetic resins, HiSiv 1000 and IRA-420 display high adsorption capacity of phenol and XAD-4 has good adsorption capability for 2-nitrophenol. These polymeric adsorbents are suitable for industrial effluents containing phenol and its derivatives as mentioned previously. It should be noted that the adsorption capacities of the adsorbents presented here vary significantly depending on the characteristics of the individual adsorbent, the extent of chemical modifications, and the concentrations of solutes.  相似文献   

12.
蜂窝状活性炭是一种新型的活性炭。简要介绍了蜂窝状活性炭的结构特性和吸附性能,重点总结了蜂窝状活性炭基催化剂的制备方法及其在催化方面的应用。  相似文献   

13.
以污泥厂剩余活性污泥作为原料,采用KOH为活化剂制备污泥活性炭,探讨了活化温度及时间、热解温度、洗涤温度及方式在污泥活性炭制备过程中的最佳工艺条件。以品红吸附量及产率作为污泥活性炭的考察指标,采用单因素实验筛选出了制备污泥活性炭的最佳工艺条件,并对污泥活性炭脱硫剂的脱硫性能进行了实验研究。实验研究结果显示,烟气中O2、水蒸气含量的多少及脱硫温度的高低会影响污泥活性炭脱硫剂的脱硫性能。  相似文献   

14.
浸渍活性炭脱除含硫气体研究进展   总被引:2,自引:2,他引:0  
介绍了近年来国内外浸渍活性炭脱除含硫气体的研究进展。讨论了活性炭表面特性对脱硫的影响,并从改变孔径分布、孔容积,引入杂原子,改变表面pH和增大硫容量等方面进行了探讨。通过浸渍可以改善活性炭的孔径分布和表面化学环境,增大硫容量,提高催化性能和转化效率。目前研究的热点是新的制备活性炭的原料和新浸渍剂,指出目前该领域存在的问题是活性炭再生困难,再生后脱硫能力恢复较少。  相似文献   

15.
Magnetic separation combined with adsorption by activated carbon has been found to be a useful method for removing pollutants. In this paper, the use of palm shell as a source of activated carbon for the removal and recovery of oil from palm oil mill effluent (POME) is studied. In the first part of the study, the properties of samples of activated carbon prepared from palm shell under a variety of different conditions were characterized for their hydrophobicity, surface areas and pore size distribution. The most effective of the activated carbon samples was prepared by impregnation with ZnCl(2) followed by combined physical/chemical activation under carbon dioxide flow at 800 °C. Four grams of these samples adsorbed 90% of the oil from 50 mL POME. In the second part, the palm shell-based carbon samples were given magnetic properties by the technique of iron oxide deposition. Ninety-four percent of the activated carbon/iron oxide composite containing the adsorbed oil could be extracted from the POME by a magnetic bar of 0.15 T. Four grams of the composite can remove 85% of oil from 50 mL POME and a total of 67% of the initial oil can then be recovered by hexane extraction. Powder X-ray diffractometry showed the presence of magnetite and maghemite in the activated carbon/iron oxide composite.  相似文献   

16.
Lignocellulosic materials are good precursors for the production of activated carbon. In this work, coffee residue has been used as raw material in the preparation of powder activated carbon by the method of chemical activation with zinc chloride for the sorption of Pb(II) from dilute aqueous solutions.The influence of impregnation ratio (ZnCl2/coffee residue) on the physical and chemical properties of the prepared carbons was studied in order to optimize this parameter. The optimum experimental condition for preparing predominantly microporous activated carbons with high pore surface area (890 m2/g) and micropore volume (0.772 cm3/g) is an impregnation ratio of 100%. The developed activated carbon shows substantial capability to sorb lead(II) ions from aqueous solutions and for relative impregnation ratios of 75 and 100%, the maximum uptake is practically the same. Thus, 75% represents the optimal impregnation ratio.Batch experiments were conducted to study the effects of the main parameters such as contact time, initial concentration of Pb(II), solution pH, ionic strength and temperature. The maximum uptake of lead(II) at 25 °C was about 63 mg/g of adsorbent at pH 5.8, initial Pb(II) concentration of 10 mg/L, agitation speed of 200 rpm and ionic strength of 0.005 M. The kinetic data were fitted to the models of pseudo-first order and pseudo-second order, and follow closely the pseudo-second order model. Equilibrium sorption isotherms of Pb(II) were analyzed by the Langmuir, Freundlich and Temkin isotherm models. The Freundlich model gives a better fit than the others.Results from this study suggest that activated carbon produced from coffee residue is an effective adsorbent for the removal of lead from aqueous solutions and that ZnCl2 is a suitable activating agent for the preparation of high-porosity carbons.  相似文献   

17.
Annual production of oil-fired fly ash in Taiwan is approximately 43 000 tons, of this approximately 13 000 tons is electrostatically precipitated, the rest is cyclonically collected. Structurewise, both consist of porous unburned carbon, vanadium and nickel oxide, and water-soluble sulfate. Electrostatically precipitated fly ash contains large amounts of ammonium sulfate. If these ashes are not properly disposed of, they become environmental problems, such as dusting, leakage of acid liquids, and pollution with heavy metals. This paper discusses the experimental extraction of vanadium and nickel from oil-fired fly ash. The results indicated that leaching of oil-fired fly ash in 0.5 N of sulfuric acid led to an extraction of 65% vanadium, 60% nickel, and 42% iron, along with an increase in the concentration of sulfuric acid. When leached in 2 N sodium hydroxide solution, the extraction of vanadium was 80%, and the extraction of nickel was negligible. If leached in an ammonia water, the extraction of nickel increased, along with an increase in the concentration of ammonia in water. When leached with 4 N ammonia water, the extraction of nickel was 60%, the extraction of vanadium was less than that obtainable from leaching in sulfuric acid solution or in sodium hydroxide solution. If electrostatically precipitated fly ash was leached in a solution of 0.25 N ammonia water and 2 N ammonium sulfate, it would yield an extraction of 60% nickel and 8% vanadium—leading to a selective extraction of nickel. This study has established an extraction flowsheet in which fly ash was first leached in an ammoniacal solution containing ammonium sulfate to recover nickel. The leached residues were then leached in an alkaline solution to recover vanadium.  相似文献   

18.
重金属以及氨氮是造成水体污染的重要物质,在对水体重金属以及氨氮的去除方法中,活性炭吸附法有一定的进展.本文参照常见的酸类物质如硝酸、盐酸、硫酸、磷酸、柠檬酸和其他酸性物质对活性炭改性去除重金属和氨氮的研究,综述了各种酸改性的机理和对活性炭的影响,定性地比较了活性炭在各种酸改性后的去除能力.总结了对酸性改性活性炭在去除重金属和氨氮应用中的发展方向和前景,对于日后用酸性废水改性活性炭以达到以废治废的功效有着指导、借鉴作用.  相似文献   

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