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1.
为了考察缺氧活性污泥对染料的吸附性能和吸附机理,以缺氧活性污泥作为吸附剂,亚甲基蓝作为吸附质进行等温吸附试验。结果表明:亚甲基蓝在缺氧活性污泥上的吸附遵循准二级速率方程,吸附方式为化学吸附;吸附行为符合Langmuir和Redlich-Peterson吸附等温式,为单分子层吸附,理论最大吸附量9.25 mg/g;亚甲基蓝分子在污泥颗粒内扩散动力学曲线存在线性部分,说明吸附过程存在污泥颗粒微孔内扩散效应。  相似文献   

2.
用振荡平衡方法,研究了非离子表面活性剂Brij35和Brij30在沉积物上的吸附行为及其对甲基对硫磷在三种沉积物上吸附的影响.结果表明:Brij35的吸附符合Langmuir型吸附等温线;Brij30的吸附符合S型吸附等温线.对于有机质含量高的沉积物,Brij35抑制甲基对硫磷的吸附,Brij30在加入浓度大于CMC时能促进甲基对硫磷的吸附,低于CMC时则抑制甲基对硫磷的吸附.对于有机质含量低的沉积物,Brij35和Brij30均能使甲基对硫磷的吸附量增加.表面活性剂对甲基对硫磷吸附行为的影响机理为吸附态和溶解态的表面活性剂对甲基对硫磷的吸附和增溶共同作用的结果,表面活性剂吸附态对甲基对硫磷吸附的贡献主要来自于吸附并集聚于沉积物表面的表面活性剂,通过分配作用进入沉积物有机质的表面活性剂吸附态贡献率小.  相似文献   

3.
黄河水体喾物对敌百虫和甲拌磷的吸附   总被引:1,自引:0,他引:1  
李桂芝  刘永明 《环境化学》2001,20(3):244-248
对敌百虫和甲拦磷在黄河水体喾物中的吸附特性进行了研究,观察了pH值和离子强度等因素对吸附的影响,结果表明,敌百虫的吸附过程为一级动力学规律;敌百虫的吸附符合Langmuir等温式,甲拌磷的吸附可用Freundich等温式较好地描述,pH值降低或离子强度增加使敌百虫和甲拦磷在沉积物中的吸附程度明显减小,敌百虫在黄河水体沉积物中的吸附以表面吸附为主,而甲拦磷则表现为表面吸附和在有机磷中的分配作用两种吸附方式。  相似文献   

4.
三种不同树脂对硫辛酸吸附行为的研究   总被引:3,自引:0,他引:3  
通过静态吸附实验,研究了XAD-4,NDA-100和ND-90树脂对乙醇.水溶液中硫辛酸的吸附热力学及动力学特性.结果表明:硫辛酸在XAD-4树脂上是单层吸附,符合Langmuir等温吸附方程,吸附过程符合准一级动力学吸附方程.在NDA-100和ND-90树脂上的吸附也符合Langmuir等温吸附方程,但并不只是单层吸附,同时兼有毛细管凝聚和微孔填充作用,吸附过程可分为大孔和中孔区吸附以及微孔区吸附两个阶段,两个阶段都符合准一级动力学吸附方程.  相似文献   

5.
黄河水体沉积物对敌百虫和甲拌磷的吸附   总被引:8,自引:0,他引:8  
李桂芝  刘永明 《环境化学》2001,20(3):244-248
对敌百虫和甲拌磷在黄河水体沉积物中的吸附特性进行了研究,观察了pH值和离子强度等因素对吸附的影响.结果表明,敌百虫的吸附过程为一级动力学规律;敌百虫的吸附符合Langmuir等温式,甲拌磷的吸附可用Freundich等温式较好地描述.ph值降低或离子强度增加使敌百虫和甲拌磷在沉积物中的吸附程度明显减小.敌百虫在黄河水体沉积物中的吸附以表面吸附为主,而甲拌磷则表现为表面吸附和在有机碳中的分配作用两种吸附方式.  相似文献   

6.
β-受体阻滞剂美托洛尔是最常用的临床治疗高血压药物,随生活污水进入污水处理系统后难以完全去除而影响生态环境,吸附是去除美托洛尔的有效方法之一.为评估美托洛尔在不同介质上的吸附行为,采用批平衡处理方法,分别探讨了吸附时间、初始浓度、溶液p H值、温度等条件下美托洛尔在污水处理厂活性污泥、珠江沉积物和湖泊沉积物上吸附行为.结果表明,3种吸附介质对美托洛尔的吸附过程均表现为先快速后缓慢的趋势,吸附平衡时间约为4 h且不受初始浓度的影响;酸性条件促进美托洛尔在介质上的吸附,离子强度的增大会抑制美托洛尔的吸附;美托洛尔在3种吸附介质上的动力学吸附过程符合伪二级动力学吸附模型,吸附常数为11.63—66.74 mg·(μg·min)~(-1).吸附过程包括物理吸附与化学吸附且以化学吸附为主,吸附反应比颗粒扩散、液膜扩散对吸附的影响更为显著,是反应的控制步骤.由于吸附介质的阳离子交换量和有机质含量的不同,3种吸附介质对美托洛尔的吸附等温线符合不同的拟合模型;热力学实验表明不同介质对美托洛尔吸附均为自发的放热反应.研究结果可为美托洛尔在天然环境中的去除技术和环境风险评价提供数据支撑.  相似文献   

7.
利用蛋壳粉对水中的磷进行吸附热力学和动力学研究.结果表明,蛋壳粉对水中的磷具有一定的吸附作用,吸附等温线符合Freundlich方程,吸附ΔH、ΔS与ΔG显示蛋壳粉对水中磷的吸附是自发吸热的物理过程.磷在蛋壳中的吸附动力学曲线存在两个吸附平台,吸附过程符合准二级动力学模型,磷在蛋壳中的吸附可能受到吸附边界层和内部孔道结...  相似文献   

8.
阿维菌素在不同类型土壤中的吸附研究   总被引:6,自引:0,他引:6  
采用Freundlich吸附等温方程研究了阿维菌素在不同类型土壤中的吸附。结果表明:阿维菌素的吸附等温线均为直线,说明吸附可能与其在土壤有机质中的分配作用有关;土壤有机质含量是影响阿维菌素土壤吸附的最重要因子,吸附系数与有机质含量呈正相关;阿维菌素有机质吸附常数平均值为2 369.185,吸附自由能为17.25~20.59 kJ.mol-1;降低水土比可以增加阿维菌素在腐殖酸和土壤中的吸附。  相似文献   

9.
沈倩  张建锋  孟晓光  车东昇 《环境化学》2014,(11):1923-1929
采用纳米氧化石墨烯(GO)吸附放射性废水中Sr2+,从吸附原理、吸附动力学、pH对吸附的影响等方面对吸附过程进行研究.采用表面增强拉曼技术和红外光谱对Sr2+在GO表面的吸附进行光谱表征.将GO负载到活性炭表面进行柱实验探索GO在废水处理中的应用.结果表明,在pH值为6.0—6.5时GO对Sr2+的吸附符合Langmuir吸附模型,最大吸附量263.16mg·g-1.GO对Sr2+的吸附符合拟二级动力学方程.在pH3—11范围内吸附量随着pH升高显著增大.GO对Sr2+的吸附具有快速,吸附量大,适用pH范围广的特点,可大量用于放射性废水的处理.GO负载到活性炭上后吸附量有所下降,但克服了GO材料本身在水中粒径小难分离的缺陷,是一种可实际应用、去除环境中Sr2+的新方法.  相似文献   

10.
吕昕  张晓健 《环境化学》1998,17(1):34-37
本文研究了邻二氯苯 和邻氯酚生物处理过程中在活性污泥上的吸附特性及影响因素。通过测定等温吸附曲线,表明这两种有机化合物在活性污泥上的吸附符合线性吸附等温式:属于在疏水键力作用下的表面物理吸附,对难溶于水的邻二氯苯具有较强的吸附能力。  相似文献   

11.
TiO2 supported on active carbon fiber (TiO2/ACF), an absorbable photocatalyst, is a new kind of material applied in air purification. In this paper, the influence of environmental temperature (T) and relative humidity (RH) on the gas-solid adsorption of toluene and the photocatalytic oxidation (PCO) efficiency of adsorbed toluene on TiO2/ACF were studied, and then, the purification capability of TiO2/ACF was estimated. PCO results showed that although the PCO efficiency increased under high RH and T levels, the amount of adsorption of toluene decreased. Moreover, quantitative analysis results of intermediates indicated that more environmental risk emerged when PCO of toluene was carried out at higher environmental T and RH levels because more toxic intermediates would be accumulated on the TiO2/ACF. So, it is significant to control the environmental T and RH conditions in the application of the PCO technique. T = 25°C and RH = 30% is the optimal condition for purifying toluene in our experimental system.  相似文献   

12.
TiO2 supported on active carbon fiber (TiO2/ACF), an absorbable photocatalyst, is a new kind of material applied in air purification. In this paper, the influence of environmental temperature (T) and relative humidity (RH) on the gas-solid adsorption of toluene and the photocatalytic oxidation (PCO) efficiency of adsorbed toluene on TiO2/ACF were studied, and then, the purification capability of TiO2/ACF was estimated. PCO results showed that although the PCO efficiency increased under high RH and T levels, the amount of adsorption of toluene decreased. Moreover, quantitative analysis results of intermediates indicated that more environmental risk emerged when PCO of toluene was carried out at higher environmental T and RH levels because more toxic intermediates would be accumulated on the TiO2/ACF. So, it is significant to control the environmental T and RH conditions in the application of the PCO technique. T = 25°C and RH530% is the optimal condition for purifying toluene in our experimental system.  相似文献   

13.
活性炭纤维的表面结构及其吸附模式   总被引:1,自引:0,他引:1  
迄今的吸附模式,Henry定律、Langmuir模型、BET模型、D-R方程、D-A方程都分别适用于不同的表面结构,对于活性炭纤维(Activated Corbon Fiber,ACF)这种特殊的炭吸附材料适用于哪种吸附模型,未见有文献专题论述。本论文在对ACF材料进行了大量表面结构研究的基础上,对ACF的表面结构与颗粒活性炭(GranularActivated Carbon,GAC)的表面进行了对比,并尝试性地对适用于ACF的吸附模式进行了计算和比较,得到了一些有价值的结论。  相似文献   

14.
杨骥  贾金平  廖黎燕 《环境化学》2006,25(3):273-276
由于活性碳纤维的吸附面积大,可以作为固相微萃取的纤维用于对环境污染物质的分析检测,包括含硫和含氯的一些有机化合物.同时,活性碳纤维具有良好的导电性能,可以作为电极,能有效地去除环境中城市污水、燃料废水和腐植酸的污染.  相似文献   

15.
载铜活性炭纤维Cu-ACF的微观结构与表面形态   总被引:2,自引:0,他引:2  
本文讨论了载铜活性炭纤维的制备过程与微观结构,表面形态的关系。  相似文献   

16.
以活性炭纤维(ACF)对水中CS:的吸附处理作为研究对象,并与另外两种活性炭(颗粒活性炭GAC和粉末活性炭PAC)进行对比研究,展示了ACF对CS:的优异吸附性能与处理效果,即吸附容量大,吸附低浓度效果好.同时运用新的宽平衡浓度吸附试验方法,测试了ACF、GAC、PAC对CS2的吸附平衡曲线,并对几种常见的吸附等温方程...  相似文献   

17.
氧化热处理对活性炭纤维吸附转化SO2能力的影响   总被引:5,自引:0,他引:5  
李开喜  凌立成 《环境化学》1999,18(3):210-215
本文研究了经O2,空气或HNO3氧化后,高温下热处理改性的活性炭纤维(ACF)在O2和水蒸气存在下脱除SO2的能力。结果表明,氧化热处理改性后,ACF的脱硫能力都有明显提高,其中O2改性的ACF脱硫活性最高,HNO3改性的ACF最低,空气改性的ACF居中。并对改性ACF具有不同脱硫活性的原因进行了分析。TPD实验表明,H2SO4从O2改性ACF上脱除最容易。  相似文献   

18.
The adsorption characteristics of 1,1,1,2‐tetrafluoroethane (HFC‐134a) on activated carbon were investigated to evaluate the recovery efficiency of HFC‐134a by six activated carbons (two granular activated carbons (GAC1 and GAC2), one high‐surface area activated carbon (HAC), and three activated carbon fibers (ACF10, ACF15, and ACF20)). HFC‐134a adsorption on the activated carbons increased with increase in the specific surface area and pore volume of the activated carbon. The differential heat of the HFC‐134a adsorption decreased with increase in the percentage of the micropore volume to the total pore volume. The adsorption model of HFC‐134a on the activated carbon could be based on the Langmuir model. The constant a of the Langmuir plot of HAC and ACF20 is smaller than GAC1 or GAC2 and ACF10 or ACF15, respectively. The constant Ws of HAC has the largest value. The constant a was correlated to the heat of adsorption. It is concluded that the largest amount of HFC‐134a was adsorbed on HAC, and the least amount of interaction occurred between HFC‐134a and the HAC. The amount of HFC‐134a adsorbed on the activated carbons over time was applied to the Sameshima equation. The adsorption rate constant of HFC‐134a on HAC was the largest. The HAC could be suitable for the recovery of HFC‐134a.  相似文献   

19.
• Cu0.15-ACF performs the best for H2S and PH3 simultaneous removal. • 550°C and 90°C are separately calcination and reaction temperatures. • The reason why Cu0.15/ACF shows better performance was found. • The accumulation of H2PO4 and SO42−(H2O)6 is the deactivation cause of Cu0.15/ACF. Poisonous gases, such as H2S and PH3, produced by industrial production harm humans and damage the environment. In this study, H2S and PH3 were simultaneously removed at low temperature by modified activated carbon fiber (ACF) catalysts. We have considered the active metal type, content, precursor, calcination, and reaction temperature. Experimental results exhibited that ACF could best perform by loading 15% Cu from nitrate. The optimized calcination temperature and reaction temperature separately were 550°C and 90°C. Under these conditions, the most removal capacity could reach 69.7 mg/g and 132.1 mg/g, respectively. Characterization results showed that moderate calcination temperature (550°C) is suitable for the formation of the copper element on the surface of ACF, lower or higher temperature will generate more cuprous oxide. Although both can exhibit catalytic activity, the role of the copper element is significantly greater. Due to the exceptional dispersibility of copper (oxide), the ACF can still maintain the advantages of larger specific surface area and pore volume after loading copper, which is the main reason for better performance of related catalysts. Finally, increasing the copper loading amount can significantly increase the crystallinity and particle size of copper (oxide) on the ACF, thereby improving its catalytic performance. In situ IR found that the reason for the deactivation of the catalyst should be the accumulation of generated H2PO4 and SO42−(H2O)6 which could poison the catalyst.  相似文献   

20.
磷酸活化粘胶基活性碳纤维吸附甲硫醚的实验研究   总被引:1,自引:0,他引:1  
不同活化条件下,以磷酸为活化剂制备粘胶基活性碳纤维(VACF),研究VACF对甲硫醚静态吸附的效果.随着活化温度的升高,活性碳纤维对甲硫醚的吸附率增大;碳化活化时间达1h后,活性碳纤维对甲硫醚的吸附性能没有明显变化;活化剂浓度为1:3(磷酸与水体积比)、浸泡的时间为10h时,活性碳纤维对甲硫醚的吸附效果最佳.  相似文献   

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