废聚苯乙烯泡沫制备颗粒活性炭

研究了以废聚苯乙烯泡沫为原料制备颗粒活性炭的工艺过程。在将聚苯乙烯炭化(600~650℃)后,采用物理活化法(水蒸气)进行了系列实验,活化时间为60 min,活化温度范围800~950℃。实验结果表明,聚苯乙烯炭化物是制备颗粒活性炭的良好原料。不定型颗粒产品灰分低于0.20%,微孔发达,碘值在1200 mg/g以上;定型活性炭比表面积在1400 m2/g以上,碘值达到1100 mg/g。     

A comparison of adsorption characteristics of various activated carbons

The physico-chemical characteristics of activated carbons obtained from different agricultural by-products by pyrolysis in a stream of water vapor have been investigated. It was established that under the same conditions of treatment the physico-chemical and adsorption characteristics of activated carbons depend on the composition of the initial raw materials. Activated carbon obtained from apricot stones has the best properties. It is characterized by a large specific surface area and micropores volume and high iodine and methylene blue adsorption activity. The activated carbons produced from cherry stones and grape seeds are characterized by predominating meso- and macropores structure. It can be supposed this is related to the larger content of lignin in those materials.     

影响大同煤生产高吸附活性炭的工艺因素

研究了炭化温度、炭化升温速度、炭化时间、活化温度、活化时间、煤炭粒度、H2 O/ C等工艺因素对大同煤生产高吸附活性炭的影响。     

粘结剂在褐煤制备粒状活性炭中的应用

考察了在褐煤半焦压块活化制备活性炭的过程中,煤焦油、废蜜糖、淀粉和纤维素四种粘结剂在成型造粒以及产品性能方面的不同作用,提出用无污染物质作为粘结剂是褐煤制备活性炭的发展方向。     

颗粒活性炭用于盐湖卤水净化脱色的研究

为降低色度对盐化工产品质量的影响,提高盐湖卤水综合利用的产品附加值,采用颗粒活性炭对盐湖卤水净化脱色.通过静态吸附实验,探讨了活性炭的用量、温度、pH对脱色率的影响.研究结果表明:每50 mL卤水加入6 g颗粒炭,在pH=2,90℃下吸附9 h,卤水脱色率达到70%.卤水自身的高离子强度和高粘度使得水分子流动性差,进而严重制约吸附效率的提高.投入大量的吸附剂和延长吸附时间亦能提高吸附效率,但成本也随之增加,在实际应用中意义不大.改善吸附工艺条件是提高吸附效率的关键所在.     

Gallic acid water ozonation using activated carbon

The ozonation of gallic acid in water in the presence of activated carbon has been studied at pH 5. Hydrogen peroxide, ketomalonic and oxalic acids were identified as by-products. The process involves two main periods of reaction. The first period, up to complete disappearance of gallic acid, during which ozonation rates are slightly improved by the presence of activated carbon. The second one, during which activated carbon plays an important role as promoter, and total mineralization of the organic content of the water is achieved. The organic matter removal is due to the sum of contributions of ozone direct reactions and adsorption during the first period and to a free radical mechanism likely involving surface reactions of ozone and hydrogen peroxide on the carbon surface during the second period. There is a third transition period where by-products concentration reach maximum values and ozonation is likely due to both direct and free radical mechanisms involving ozone and adsorption. Discussion on the mechanism and kinetics of the process is also presented both for single ozonation and activated carbon ozonation.     

Advanced oxidant reactivity pertaining to granular activated carbon beds for air pollution control

The Pennsylvania State University is researching an advanced oxidation system, which includes an air-phase photolytic chamber, an air/water stripping tower, and granular activated carbon (GAC) beds, for controlling volatile organic compounds (VOCs).A laboratory-scale experimental procedure has been employed that simulated certain aspects of several full-scale installations. The apparatus has been used to characterize the loading capacity and mass transfer zone of selected VOCs on coconut shell GAC. The GAC bed has then been placed in series with an ultraviolet reactor, which generates ozone and advanced oxidants in order to regenerate the loaded GAC at intensities of advanced oxidants that were higher than full-scale installations.VOC loading tests revealed that the adsorption of methyl isobutyl ketone (MIBK) was characterized by a well-defined mass transfer zone. Upon exposure to UV/O₃, desorption and/or destruction of the MIBK and other VOCs occurred most prominently within the first inch of the GAC bed. This correlated with the penetration of advanced oxidants into the GAC bed, which also occurred most significantly in the bed's first inch. However, the amount of oxidant penetration increased with time. The removal of oxidants from air by GAC was accompanied by a decrease in mass of the GAC. The ability of oxidants to penetrate a GAC bed was altered when the bed was loaded with a VOC.     

颗粒活性炭的特性参数与吸附性能的关系试验

采用活性炭进行饮用水的深度处理,选择适合原水水质的活性炭至关重要,通过6种不同颗粒活性炭特性参数的测试,对饮用水有机物的吸附试验以及吸附等温线的测定,结果表明:针对颗粒活性炭的筛选,碘值,亚甲蓝值,吸附等温线的KF及斜率1/n值均不能单独作为评价筛选活性炭优劣的指标,而应综合考虑颗粒活性炭的孔径分布与原水中有机物的相对分子质量分布相匹配等。研究还表明:碘值,亚甲蓝值,吸附等温线的KF存在一定的相关性,从颗粒活性炭的特性参数和吸附性能参数可以推测活性炭滤柱试验吸附效果。颗粒活性炭用于饮用水深度处理,能去除水中相对分子质量小的有机物,处理的水量为颗粒活性炭体积的4800倍时,对CODMn的去除率为15%左右。     

活性炭改性对用于甲酸分解的Pd/活性炭催化剂的影响

采用磁力搅拌法和水浴振荡法制备应用于甲酸分解的Pd/活性炭(AC)催化剂,研究了活性炭载体改性和制备方法对催化剂分解甲酸性能的影响。采用恒温水浴振荡装置,在80℃水浴中进行甲酸催化分解反应,以甲酸的催化分解率评价催化剂催化活性。结果表明,以经过不同的酸、碱、盐溶液改性后的活性炭为载体采用不同方法制备的Pd/AC催化剂对甲酸的催化分解效果不同,以Na2CO3改性的活性炭为载体采用磁力搅拌法制备的催化剂活性最好,甲酸水溶液的分解率达85%以上,含甲酸的工业废水的分解率达70%。     

活性炭吸附法脱硫实验研究和工业性应用

研究了周期性水洗涤脱附对活性炭脱硫性能的影响。经过 4次吸附、脱附循环后 ,活性炭的动态吸附性能和脱附性能达到平衡。活性炭颗粒越小 ,床层穿透时间越长 ,脱硫效率越高。当进口SO2 质量分数为 3× 1 0 - 3时 ,活性炭脱硫效率达到96 %以上。工业性实验表明 ,采用水洗涤脱附 ,活性炭脱硫效率稳定。燃煤烟气工业性实验排放烟气SO2 质量分数小于 9×1 0 - 5,脱硫效率达到 93 %。     

Kinetics of removal of p-toluene sulphonic acid from concentrated solution by granular activated carbon

The removal of p-toluene sulphonic acid (p-TSA) from concentrated solution by granular activated carbon (GAC) was studied in batch experiments. The first order rate constant was found to be 5.5010 × 10^?5 s^?1 for a solution of 1000 mg dm^?3. In order to establish the rate limiting step the pore and film diffusion coefficients were calculated from the half time equations. Film diffusion was found to be rate limiting. The average value of the external mass transport rate constant was 2.91 × 10^?6 cm s^?1. The adsorption isotherm was adequately described by the Langmuir model and belongs to type ‘H’ of Giles' classification.     

活性炭颗粒载体厌氧同步去除COD和含氮污染物

以活性炭颗粒为填料构建厌氧污水处理系统。以葡萄糖作为单一碳源,当进水中葡萄糖的质量浓度为500 mg/L时,COD的去除率最高为87.9%。系统对NH4+-N和NO3--N的最高去除率分别为60.3%和95.2%;同时出水中NO2--N没有明显的积累,始终低于0.55 mg/L。这表明以活性炭为填料的厌氧污水处理系统能有效降低反硝化菌及其代谢产物对厌氧消化菌的抑制,实现COD和含氮污染物的协同、高效去除。     

Control of bio-regenerated granular activated carbon by spreadsheet modelling

The optimisation of water purification with biological activated carbon (BAC) is described. Procedures are suggested to control biofilm growth and to use bio-indicators to predict TOC (total organic carbon) and COD (chemical oxygen demand) removal efficiencies. Empty bed contact time (EBCT) was a major physical control parameter. Dissolved oxygen (DO), pH and nutrients of the influent were controlled according to the abundance of bacteria, protozoa and rotifers. Numbers of micro-organisms in BAC beds were determined. Certain genera of ciliated protozoa, representing healthy environmental conditions, were employed as biological indicators for system performance during biological regeneration of exhausted granular activated carbon (GAC). There was a strong positive correlation between the abundance of some protozoa in the liquid phase of the BAC bed and COD concentration in the effluent. Mathematical spreadsheet models were constructed to estimate COD removal efficiency of BAC filters with different loading rates, DO, pH, nutrient requirements and populations of micro-organisms. © 1998 SCI     

活性炭对重金属离子的吸附研究

研究了活性炭分别对铅、镉、铜及锌离子的吸附作用,研究了pH值、温度及活性炭的投加量等因素对吸附效果的影响。结果表明,当pH〉5时对四种离子的去除率均达到98％以上,能达到很好的吸附。低温有利于吸附的进行。随着活性炭的增加．重金属离子的去除率增加．而且铜离子的活性炭最佳用量是0．3000g．铅、镉和锌的活性炭最佳用量均为1．000g。随着吸附时间的增加,去除率上升。铜、铅、镉和锌离子的吸附平衡时间分别为3．5h、1h、1．5h和1．5h。铜离子的吸附符合Langmuir等温模式,而锌、铅和镉离子的吸附符合Freundlich等温模式。     

中孔煤基磁性活性炭的制备及性能表征

为提高活性炭的回收性能,以褐煤为原料,Fe3O4为赋磁剂,采用一步法制备了中孔煤基磁性活性炭,并通过低温氮气吸附、X射线衍射光谱(XRD)和振动样品磁强计(VSM)对磁性活性炭的比表面积、孔隙结构、赋磁剂晶型、磁性能进行表征,研究了炭化和活化条件对磁性活性炭性能的影响。结果表明,Fe3O4不仅能催化炭烧蚀,而且能赋予活性炭磁性,最终以生成的Fe O、γ-Fe2O3和未反应的Fe3O4形式分散在磁性活性炭内。在Fe3O4添加量6%,炭化温度650℃,炭化60 min,活化温度930℃,活化时间120 min,水蒸气流量0.77 g/(g·h)的优化工艺条件下,煤基磁性中孔活性炭的比表面积达到370 m2/g,中孔率达到55.7%,比饱和磁化强度1.36 emu/g,剩磁0.46 emu/g,矫顽力643.17Oe,比磁化率7.19×10-6m3/kg。该煤基磁性活性炭属弱磁性矿物类,可采用强磁选机进行磁选回收。     

中空活性碳纤维概述

中空活性碳纤维以其独特的结构而具有比活性炭和活性碳纤维更优异的性能,本文概述了中空活性碳纤维的制备过程及其应用,并指出,其作为吸附储氢材料具有一定前景。     

二氧化碳再生乙酸乙烯合成用触媒载体活性炭

提出用二氧化碳活化法再生乙酸乙烯合成用触媒载体活性炭工艺。研究了活化温度、活化时间和二氧化碳流量对活性炭吸附性能和得率的影响。确定最佳工艺条件为活化温度1 273 K,活化时间100 m in,二氧化碳流量0.5 L/m in,在此条件下得到的活性炭碘吸附值为1 091.33 mg/g,乙酸吸附值为518.30 mg/g,强度为72%,活化得率为80.33%,并对制得的活性炭做了比表面积测定和孔结构分析。再生后的活性炭强度和乙酸吸附值均达到标准,符合乙酸乙烯合成用触媒载体活性炭的要求。     

吸附苯酚活性炭微波辅助溶液再生效果

分析了p H对颗粒活性炭(GAC)吸附苯酚性能的影响。实验选择质量分数为1%Na OH溶液,采用微波辅助溶液再生的方法,对吸附苯酚的GAC进行再生研究,探讨实验因素对GAC再生效率的影响。实验结果表明:最佳的再生条件为微波功率520 W、再生时间1.5 min、Na OH再生辅助溶液用量10 m L,此时GAC再生效率为95.6%。在最佳再生条件下,经过6次再生后GAC的吸附能力依然很强。     

Sulfur removal from model diesel fuel using granular activated carbon from dates’ stones activated by ZnCl2

Samples of granular activated carbon (GAC) were produced from dates’ stones by chemical activation using ZnCl₂ as an activator. Textural characteristics of GAC were determined by nitrogen adsorption at 77 K along with application of BET equation (Brunauer, Emmett and Teller) for determination of surface area. Pore size distribution and pore volumes were computed from N₂ adsorption data by applying the nonlinear density function theory (NLDFT). FT-IR spectra of GAC samples were also obtained to determine the functional groups present on the surface. GAC samples were used in desulfurization of a model diesel fuel composed of n-C₁₀H₃₄ and dibenzothiophene (DBT) as sulfur containing compound. More than 86% of DBT is adsorbed in the first 3 h which gradually increases to 92.6% in 48 h and no more sulfur is removed thereafter. The adsorption data were fitted to both Freundlich and Langmuir equations to estimate the adsorption parameters. The optimum operating conditions for GAC preparation based on high adsorption capacity are T_carb = 700 °C, θ_carb = 3.0 h and R = 0.5. Moreover, the efficiency of sulfur removal by GAC is reduced when applied to commercial diesel fuel. Finally, linear regression of experimental data was able to predict the critical pore diameter for DBT adsorption (0.8 nm) and validating the reported impact of average pore diameter of activated carbon on the adsorption capacity.     

超级电容器用煤基活性炭研究

为了研究煤基活性炭电极对超级电容器性能的影响规律,根据超级电容器的工作原理,阐述了比表面积、孔径分布、表面官能团、石墨化程度、灰分及粒度对电化学性能的影响。研究表明适宜的中孔比例和粒度有利于电解液的扩散;含氧和含氮官能团可以改善电极的表面润湿性;无定型炭结构孔隙更发达,更适合作为活性炭材料;降低灰分可以提高电极的充放电特性和倍率特性。