对二甲苯在活性炭固定床上的吸附动力学

研究了对二甲苯在活性炭固定床上的吸附动力学。考察了初始浓度、气体流量、床层长度等因素对吸附透过曲线的影响。同时,采用Yoon—Nelson模型对吸附透过曲线进行线性回归分析。实验结果表明,随着初始浓度的增大,透过时间缩短,吸附量增大：气体流最对透过曲线的形状影响不大：床层长度基本不影响透过曲线;Yoon-Nelson模型可以较好的模拟固定床吸附过程。     

微纤包覆活性炭复合材料的制备和应用研究

以微米尺度的不锈钢纤维、活性炭和针叶木纤维为原料,通过湿法造纸和烧结工艺制备了微纤包覆活性炭复合材料。采用正交试验优化,确定了微纤复合材料的最优制备工艺。利用SEM考察了通过最优制备工艺所得复合材料的微观结构,并采用氮气吸附法测定了原活性炭与微纤复合材料中活性炭的孔径分布和比表面积。结果表明,在活性炭和纤维的质量比为13:6,面积尺寸为6 cm 12 cm的烧结压片质量为212 g,于1050℃下烧结20 min所制得的微纤复合材料炭包覆率达到64.3%。不锈钢纤维的连接处被很好地融合在一起,形成一个烧结锁定的三围网络,将活性炭颗粒很好地包覆起来。活性炭在包覆前后的孔结构特性基本保持不变,比表面积分别为678 m2 g 1和769 m2 g 1。通过在固定床层的进口端和出口端分别装填颗粒活性炭和微纤复合材料形成复合床层,测定了甲苯在此复合床层上的吸附透过曲线,并与颗粒活性炭固定床层的实验结果进行比较。结果表明,在相同的条件下,复合床较传统固定床在1%的透过浓度下吸附透过时间延长了大约15 min。     

活性炭对甲苯的吸附及其等温线预测

以微波椰壳活性炭和微波再生后的活性炭吸附甲苯.测定了在20,30和40℃条件下甲苯在活性炭上的吸附等温线,采用Langmuir方程对实验数据进行拟合.结果表明,在30℃下椰壳活性炭和再生活性炭吸附甲苯的理论饱和吸附量分别为0.323 和0.273 g/g;采用Polanyi吸附势理论预测了苯在活性炭上的吸附等温线,其中...     

测定活性炭吸附甲苯等温线的试验方法

介绍了一种活性炭吸附甲苯的吸附等温线的试验方法。     

测定活性炭吸附甲苯等温线的试验方法

介绍一一种活性炭吸附甲苯的吸附等温线的试验方法     

活性炭吸附甲苯动力学研究

以柱状活性炭为吸附剂,在空塔气速V为3.54cm/s,气体停留时间t为30s,入口气体中甲苯浓度Ci为1800～2400mg/m3的实验条件下,研究活性炭的甲苯吸附性能。根据吸附穿透曲线,求得活性炭吸附容量为0.179kg(甲苯)/kg(活性炭),传质区高度为12.7cm,并用Moment理论处理吸附过程,得到活性炭吸附甲苯的理论穿透曲线模型。     

活性炭对低浓度萘的吸附性能

以萘为模型化合物,采用固定床反应器研究了不同温度和表观气速下GH-8活性炭对萘的吸附行为,以Yoon-Nelson模型对实验数据进行拟合,得到模型参数kYN=0.20 h-1,kYNτ=51.404-0.166T+0.292/u.采用传质区模型预测了萘在活性炭床层上的传质区长度及其移动速度,实验值和预测值的最大相对偏差小于10%.     

活性炭孔结构对甲苯及丙酮吸附性能的影响

采制3种活性炭样品进行甲苯、丙酮吸附实验,以重量法计算活性炭对甲苯、丙酮气体的饱和吸附率,并将活性炭物性参数与其关联。结果表明,活性炭物性与其对有机物的吸附性能密切相关,活性炭碘吸附值、总比表面积与甲苯吸附率成明显的负相关,较高中孔与总孔比(V_(mes)/V_t)会促进对甲苯的有效吸附;微孔比表面积和孔容积越大,活性炭对丙酮的吸附效果越好。此外,线性回归分析的结果表明,活性炭中孔径小于1.4 nm的微孔及合理的孔径分布对甲苯的吸附起主要作用,孔径1.67～2.22 nm是吸附丙酮的有效孔径。     

活性炭纤维吸附甲苯废气的中试研究

介绍了活性炭纤维吸附甲苯废气试验的装置和流程,并记录了吸、脱附试验的数据。经该工艺处理后的甲苯废气可达标排放,并且运用热风反吹吸附后的装置可达到解吸目的。     

粘胶基活性炭纤维对甲苯的吸附及再生

在自制的实验装置上,研究了粘胶基活性炭纤维(ACF)对甲苯气体的吸附及其吸附饱和后采用高温水蒸气解吸、再生。正交实验表明,甲苯气体流量、浓度和粘胶基ACF的填充高度对吸附过程都有显著的影响。最佳操作参数为:温度13.0℃、粘胶基ACF用量1.50 g、填充高度15 cm、甲苯气体流量0.8 m3/h、甲苯进口平均浓度89.7 mg/m3,脱附平均温度136.0℃时,粘胶基ACF对甲苯气体吸附再生效果较好。验证了粘胶基ACF的吸附量与气体进口浓度成正比,与气体流量成反比关系。     

Preparation of Microfibrous Entrapped Activated Carbon Composites and its Application for Benzene Adsorption

Microfibrous composites consisting of 150-200 μm activated carbon particles entrapped in 6.5 μm stainless steel fibers were prepared by wet layup papermaking and sintering process. The effects of a variety of operation parameters on the properties of microfibrous composites were investigated. The composite bed with microfibrous entrapped activated carbon was developed to purify air contaminated with benzene. The experimental results showed that the microfibrous composite with a ratio of 13:6 (W/W, carbon/ fibers) was of a relatively higher carbon entrapment ratio under the conditions of adding 2 L water, stirring at 50 Hz for 10 min, and then sintering at 1050^°C for 20 min. The breakthrough time of 5.0 cm composite bed increased by 28 min compared with that of a 5.0 cm individual GACs bed, and bed utilization increased 18.4% at 1% breakthrough concentration. The Bohart-Adams and Yoon-Nelson models were applied to analyze the experimental data of composite bed. The Bohart-Adams model fitted well with the experimental data for the C/C₀ region up to 0.5 but showed large discrepancies above this value. The Yoon-Nelson model predicted values were in very good agreement with the experimental results in the C/C₀ region above 0.05.     

活性炭吸附苯、甲苯废气的研究

研究了苯、甲苯组成的混合溶剂系统的吸附平衡关系及动力学性质。采用动态吸附法对纯组分、混合组分的吸附情况进行了测定。 根据Langmuir方程拟合出相应的平衡常数qe和K。通过对二组分吸附的穿透曲线进行分析,发现吸附能力强的甲苯能从活性炭中置换出吸附能力弱的苯。整个吸附过程分为三个阶段进行。分别利用E-L方程和IAST理论进行理论预测分析,并与实验结果进行了比较。结果表明,虽然E-L方程对吸附总量的预测与实验结果较为吻合,但对各个组分吸附量的预测却经常产生正负偏差;而IAST引入竞争模型,较好地消除了这种正负偏差,平均误差不超过10%,与实验结果更为吻合。     

甲苯吸附与活性炭孔隙结构关系的研究

选用4种活性炭为吸附剂,7.537 g/m3甲苯为吸附质,在298.15 K下进行吸附试验,探讨了4种活性炭的甲苯吸附量与其比表面积和孔容的关系。对活性炭不同孔径区间的孔容和甲苯吸附量进行线性回归分析,并对分析结果进行显著性检验。结果表明:4种活性炭均具有微孔吸附特征;活性炭比表面积、孔容大则其甲苯吸附量大,活性炭孔径结构对甲苯吸附效果产生直接影响;孔径在0.8～2.4 nm之间的孔容和甲苯吸附量之间存在较好的线性关系,其线性相关度R最大。     

Adsorption of Ibuprofen and Atenolol at Trace Concentration on Activated Carbon

Abstract

Adsorption isotherms of atenolol and ibuprofen onto activated carbon (AC) at trace concentration in water (initial concentration, 80 μg/L – equilibrium concentration as low as 0.13 μg/L) are presented in this paper. Their adsorption was studied considering two ACs (F400 and Picabiol) showing different textural and chemical characteristics. Experiments were performed in buffered ultrapure water with and without humic acids to evaluate their influence on adsorption. It was found that adsorption was not in agreement with expectations based either on the log K_ow or log D values of the target compounds. Adsorption mechanisms were discussed and the experimental isotherms were modelled.     

Adsorption of Gallic Acid from Aqueous Solution Using Fixed Bed Activated Carbon Columns

Naturally occuring matter (NOM), a heterogeneous mixture of complex organic compounds, is invariably present in all surface and ground waters. These materials act as substrate for the growth of bacteria in the distribution system. The disinfection of such water by chlorination produces disinfection by products consisting of several halogenated compounds which are toxic and carcinogenic. As gallic acid is the building block of most NOM, its adsorptive removal from water has been studied using activated carbon columns. The operating variables studied are the hydraulic loading rate (HLR), bed depth (Z), and the feed concentration (C_o). The breakthrough curves are S-shaped and the breakthrough time increases with increasing Z and decreases with increasing HLR and C_o. The adsorption increases with increasing HLR and is maximum around HLR = 8 m³/hr/m². The column design parameters such as the critical bed depth and the depth of the mass transfer zone (MTZ) as calculated using the bed depth service time (BDST) approach are found to agree fairly closely with the experimental values. MTZ is smaller for the carbon cloth indicating its better adsorption characteristics. The adsorption column parameters such as the treated volume and the mass of the carbon required for a desired effluent concentration have been determined from the column data.     

热改性活性炭纤维对甲苯的吸附和分形分析

在氮气气氛中,N2的流量为100 mL/min,分别在450℃和950℃并均加热30 min制备了活性炭纤维的热改性样品,分别改性样品记为ACF1和ACF2。分别考察了未改性样品ACF0和改性样品ACF1及ACF2对低浓度甲苯的吸附等温线。基于甲苯吸附等温线,利用Mandelbrot分形理论对3种ACF样品进行了分形维数(Df)的分析,计算得到3种ACF样品的Df值分别为Df,0=2.542 5,Df,1=2.569 2,Df,2=2.573 4,从分形理论角度解释了热改性改善ACF吸附性能的原因。最后通过对ACF样品的表征数据验证了试验结果和ACF结构分形分析的正确性。     

数值积分法求解低浓度甲苯固定床吸附数学模型

在低浓度范围用直接积分法代替龙格库塔法求解活性炭固定床吸附甲苯蒸气数学模型,预测结果与实验结果比较表明,计算结果与实验结果吻合良好,所建模型可用于低浓度范围内预测其它情况下的穿透曲线