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1.
Biosorption of cadmium(Ⅱ) and lead(Ⅱ) ions from aqueous solutions onto dried activated sludge 总被引:6,自引:0,他引:6
WANG Xue-jiang XIA Si-qing CHEN Ling ZHAO Jian-fu CHOVELON Jean-mar NICOLE Jaffrezic-renault 《环境科学学报(英文版)》2006,18(5):840-844
The removal of heavy-metal ions from aqueous solutions by using dried activated sludge has been investigated in batch systems. Effect of solution pH, initial metal ion concentration, and temperature were determined. The results of the kinetic studies showed that the uptake processes of the two metal ions(Cd(Ⅱ) and Pb(Ⅱ)) followed the pseudo-second-order rate expression. The equilibrium data fitted very well to both the Langmuir and Freundlich adsorption models. The FT-IR analysis showed that the main mechanism of Cd(Ⅱ) and Pb(Ⅱ) biosorption onto dried activated sludge was their binding with amide I group. 相似文献
2.
Chunping Yang Jiaqiang Wang Min Lei Gengxin Xie Guangming Zeng Shenglian Luo 《环境科学学报(英文版)》2010,22(5):675-680
3.
WANG Xue-jiang XIA Si-qing CHEN Ling ZHAO Jian-fu CHOVELON Jean-marc NICOLE Jaffrezic-renault 《环境科学学报(英文版)》2006,18(5)
The removal of heavy-metal ions from aqueous solutions by using dried activated sludge has been investigated in batch systems. Effect of solution pH, initial metal ion concentration, and temperature were determined. The results of the kinetic studies showed that the uptake processes of the two metal ions(Cd(Ⅱ) and Pb(Ⅱ)) followed the pseudo-second-order rate expression. The equilibrium data fitted very well to both the Langmuir and Freundlich adsorption models. The FT-IR analysis showed that the main mechanism of Cd(Ⅱ) and Pb(Ⅱ) biosorption onto dried activated sludge was their binding with amide I group. 相似文献
4.
Xuejiang Wang Siqing Xia Jianfu Zhao 《Frontiers of Environmental Science & Engineering in China》2008,2(2):198-202
The biosorption of Direct Black 38 by dried anaerobic granular sludge in a batch system under specific temperatures and initial
pH was investigated. The adsorption reaction is pH dependent with higher removal at low pH. The adsorption equilibrium data
fit very well with both Langmuir and Freundlich models in the concentration range of Direct Black 38 at all chosen temperatures.
The adsorption parameters show that the adsorption of Direct Black 38 is an endothermic and more effective process at high
temperatures. The kinetics of adsorption was found to be second order and adsorption rate constants increased with increasing
temperature. Activation energy was determined as 26.8 kJ/mol for the process. This suggests that the adsorption of Direct
Black 38 by dried anaerobic granular sludge is chemically controlled. 相似文献
5.
Activated sludge was immobilized into Ca-alginate beads via entrapment, and biosorption of three heavy metal ions, copper(Ⅱ), zinc(Ⅱ), and chromimum(Ⅱ), from aqueous solution in the concentration range of 10-100 mg/L was studied by using both entrapped activated sludge and inactivated free biomass at pH≤5. A biphasic metal adsorption pattern was observed in all immobilized biomass experiments. The biosorption of metal ions by the biosorbents increased with the initial concentration increased in the medium. The adsorption rate of immobilized pre-treated activated sludge(PAS) was much lower than that of free PAS due to the increase in mass transfer resistance resulting from the polymeric matrix. Biosorption equilibrium of beads was established in about 20 h and the adsorbed heavy metal ions did not change further with time. No significant effect of temperature was observed in the test for free biomass while immobilized PAS appeared to be strong temperature dependent in the test range of 10 and 40℃.Besides, the content of activated sludge in the calcium alginate bead has an influence on the uptake of heavy metals. The sorption equilibrium was well modeled by Langmuir isotherm, implying monomolecular adsorption mechanism. Carboxyl group in cell wall played an important role in surface adsorption of heavy metal ions on PAS. 相似文献
6.
活性污泥对病毒的生物吸附特性 总被引:1,自引:2,他引:1
针对污水处理过程中可能存在的病原微生物对人体健康的风险,以f2噬菌体为模型病毒,采用静态吸附方法,研究病毒在活性污泥上的生物吸附特性及其影响因素,以期了解病毒在活性污泥处理系统中固液两相体系的分配规律.结果表明,活性污泥对病毒的吸附速率快,吸附量大,在120 min时即能达到吸附平衡,平衡吸附率高达96%以上,对病毒的去除效果较为理想;该吸附符合Freundlich吸附等温式,且吸附率随着病毒浓度的增加而呈现出下降趋势;另外,pH值、金属阳离子浓度及有机物浓度均可显著影响病毒在活性污泥上的吸附. 相似文献
7.
厌氧颗粒污泥对五氯酚(PCP)的吸附、解吸及生物降解 总被引:5,自引:0,他引:5
以未驯化污泥接种的升流式厌氧污泥床反应器可形成降解五氯酚(PCP)的颗粒污泥.颗粒污泥去除PCP的主要机制是生物降解作用,而不是生物吸附作用.PCP在颗粒污泥上的吸附和解吸符合Freundlich等温方程,吸附和解吸的Freundlich常数K、1/n分别为0.7857mg/gSS、0.5079和1.1095mg/gSS、0.3782,部分PCP被不可逆吸附.与其它活或死的生物材料相比,本试验形成的颗粒污泥对PCP吸附量较小.该方程较准确地表达了UASB反应器内厌氧颗粒污泥对PCP吸附量的变化规律. 相似文献
8.
研究了MBR中灭活污泥对雌酮(El)的吸附行为,考察了污泥浓度、污泥粒径和El初始浓度对E1吸附效果的影响,并探讨了不同污泥组分(悬浮颗粒、胶体和溶解物)对E1的吸附作用贡献.结果表明,在E1初始浓度为l~500μg·L-1,4h左右达到吸附平衡;E1的吸附符合Freundlich吸附模型,呈线性吸附;E1初始浓度越大,吸附速率越小.随着污泥浓度升高,单位污泥对E1的吸附量显著下降,出现了固体浓度效应;而吸附去除率却随着污泥浓度的升高而显著增加,且两者之间呈显著正相关(p<0.05).活性污泥对E1的单位吸附容量随着污泥粒径增大而减小.污泥中悬浮颗粒、胶体和溶解物的含量分别为87.8%、9.6%和2.6%,吸附平衡时,E1在3种组分中的浓度分别为13.9 μg·g-1、24.1 g·g-1和12.5 μg· g-1,胶体吸附效果最好.不同组分对E1的吸附贡献与其含量正相关,吸附贡献为:悬浮颗粒>胶体>溶解物. 相似文献
9.
采用微波辅助磷酸活化制备了高中孔率蔗渣基介孔炭,并通过硝酸氧化和乙二胺聚合在其孔道内修饰了含氮多胺基团,探索了溶液浓度、温度、吸附剂剂量等对改性介孔炭的Pb(II)吸附性能、行为和热力学特性的影响.结果表明,蔗渣基介孔炭较宽的孔道结构可通过乙二胺缩水聚合反应在其表面接枝酰胺、仲胺等含氮基团;胺化改性增强化了介孔炭对水溶液中Pb(II)的固定作用,改性后介孔炭对Pb(II)的吸附量高达180mg/g,是改性前介孔炭的1.5倍;改性介孔炭对Pb(II)的去除率显著增加,对溶液浓度<60mg/L的Pb(II)去除率接近100%.等温吸附与热力学数据表明,胺化改性介孔炭对Pb(II)的吸附位能量存在差异化,吸附是自发的吸热反应过程,温度对铅(II)离子吸附有促进作用,化学作用在吸附过程中发挥了重要作用. 相似文献
10.
厌氧颗粒污泥对有机物的初期吸附 总被引:5,自引:0,他引:5
在实验室条件下,以静态、序批的方法研究了厌氧颗粒污泥对废水中有机物的初期吸附特性及环境条件对吸附能力的影响.结果表明.与好氧活性污泥相似,厌氧颗粒污泥对有机物的初期吸附速度很快,在10min左右就能达到假定的吸附平衡.初期吸附作用的类型主要表现为物理吸附,占总吸附去除COD的70%左右,其吸附等温线与Freundlich型拟合得较好(R2=0.9702).pH是影响吸附的重要因素,在pH值为5~9的范围内,吸附量较大.平均为131.19mg·g-1.,当pH值大于9或小于5时,吸附量逐渐下降;温度对吸附也有一定的影响,但影响程度不明显. 相似文献
11.
为研究城市污水厂污泥对水中硫化物的吸附特性,从3座城市污水处理厂采集回流污泥,考察了硫化物浓度、温度、pH值和其他离子对污泥吸附硫化物的影响.结果表明,污水厂回流污泥对硫化物的吸附等温线可以用Langmuir方程很好地描述,其最大硫化物吸附量为15~27mg/g-干污泥.在温度为5~35℃条件下,吸附量随温度上升而增加,表明该吸附为吸热过程.pH值在2~7范围内,pH值对污泥吸附硫化物的影响不大,当pH值低于2时,污泥对硫化物的吸附量随pH降低显著减小.硫化物可能以离子形式被污泥吸附,该过程为化学吸附过程.水中存在0~25mg/L Cl-或0~12mg/L SO2- 4不影响污泥对硫化物的吸附量. 相似文献
12.
两种形态的活性炭纤维对水中敌草隆吸附性能的对比 总被引:3,自引:0,他引:3
探讨了粉末和片状两种形态的活性炭纤维对水中敌草隆的吸附行为.结果表明: 粉末活性炭纤维的前期吸附速率较快,平衡吸附量大,但达到吸附平衡的时间较长;pH对两者的平衡吸附量的影响趋势一致,且片状活性炭纤维和粉末状活性炭纤维的最佳pH值分别为2.9和3.1;敌草隆在两种活性炭纤维上的吸附皆为多分子层吸附,吸附行为均适宜采用Redlich-Peterson方程进行描述;假二级方程均适用于描述两种形态活性炭纤维对水中敌草隆的吸附动力学过程,但相比较而言,粉末活性炭纤维动力学拟合的相关性差异更加明显;两者的吸附Gibbs自由能(ΔG0)值均小于零,说明两者的吸附过程皆为自发进行的吸附过程.但值得注意的是,片状活性炭纤维的焓变ΔH0>0,说明该吸附反应为吸热反应;粉末活性炭纤维的焓变ΔH0<0,说明该吸附反应为放热反应. 相似文献
13.
鸟粪石-沸石复合材料对水中镉的吸附性能研究 总被引:2,自引:0,他引:2
研究以氧化镁负载沸石回收污水中氮磷得到的鸟粪石-沸石复合材料(STR-NZ)为吸附剂,用于对水体中重金属镉的吸附去除.实验采用SEM-EDS、XRD和FTIR等手段对STR-NZ材料进行表征,并考察了投加量、初始pH和反应时间等对STR-NZ材料去除水中Cd~(2+)的影响.结果表明:氧化镁负载沸石材料主要以鸟粪石沉淀的方式实现对水中磷酸盐和氨氮的回收;STR-NZ对水溶液中Cd~(2+)的吸附量随pH的增大呈先增加后趋于平衡的趋势,当Cd~(2+)的初始浓度为50 mg·L~(-1)时,STR-NZ的最佳投加量为0.2 g·L~(-1),Cd~(2+)最大吸附量为249.35 mg·g~(-1), STR-NZ对Cd~(2+)的吸附动力学符合准二级动力学模型,对Cd~(2+)的等温吸附符合Langmuir等温吸附模型,STR-NZ主要通过Cd_5(PO_4)_3(OH)沉淀的方式实现对水中Cd~(2+)的去除. 相似文献
14.
Thermodynamics and kinetics of cadmium adsorption onto
oxidized granular activated carbon 总被引:3,自引:0,他引:3
Cadmium sorption behavior of granular activated carbon oxidized with nitric acid was systematically studied by sets of the equilibrium and time-based experiments under various conditions.The cadmium adsorption capacity of oxidized granular activated carbon enlarged with an increase in pH,and reduced with an increase in ionic strength.Experimental data were evaluated to find out kinetic characteristics.Adsorption processes were found to follow pseudo-second order rate equation.Adsorption isotherms correlate well with the Langmuir isotherm model and the maximum sorption capacity of cadmium evaluated is 51.02μmol/g.Thermodynamic parameters were calculated based on Van't Hoff equation.Equilibrium constant Kd was evaluated from Freundlich isotherm model constants,Langmnir isotherm model constants,and isotherms,respectively.The average change of standard adsorption heatΔH~0 was -25.29 kJ/mol.NegativeΔH~0 andΔG~0 values indicate the adsorption process for cadmium onto the studied activated carbon is exothermic and spontaneous.The standard entropyΔS~0 was also negative,which suggests a decrease in the freedom of the system. 相似文献
15.
Megat Hanafiah Megat Ahmad Kamal Wan Mat Khalir Wan Khaima Azir MohamedKasmawati Zakaria Haslizaidi Wan Ngah Wan Saime 《环境科学学报(英文版)》2010,22(2):248-256
Rubber leaf powder (an agricultural waste) was treated with potassium permanganate followed by sodium carbonate and its
performance in the removal of Pb(II) ions from aqueous solution was evaluated. The interactions between Pb(II) ions and functional
groups on the adsorbent surface were confirmed by Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy
(SEM) coupled with X-ray energy dispersive spectroscopy (EDX). The effects of several important parameters which can affect
adsorption capacity such as pH, adsorbent dosage, initial lead concentration and contact time were studied. The optimum pH range
for lead adsorption was 4–5. Even at very low adsorbent dosage of 0.02 g, almost 100% of Pb(II) ions (23 mg/L) could be removed.
The adsorption capacity was also dependent on lead concentration and contact time, and relatively a short period of time (60–90
min) was required to reach equilibrium. The equilibrium data were analyzed with Langmuir, Freundlich and Dubinin-Radushkevich
isotherms. Based on Langmuir model, the maximum adsorption capacity of lead was 95.3 mg/g. Three kinetic models including pseudo
first-order, pseudo second-order and Boyd were used to analyze the lead adsorption process, and the results showed that the pseudo
second-order fitted well with correlation coefficients greater than 0.99. 相似文献
16.
重金属铬(Cr(VI))是废水中常见的、困扰很多污水生物处理系统运行效果的污染物.本文通过静态试验和静态冲击试验,研究了Cr(VI)在活性污泥系统中的分布特点和对硝化效率、活性等的影响,并进行了模型分析.结果表明,活性污泥对Cr的吸附很快,但吸附量有限,Cr(VI)投加浓度为1、5、10和30 mg · L-1的溶液中,Cr的12 h-吸附量分别为0.79、1.98、3.19和5.78 mg · g-1.Cr(VI)投加到活性污泥混合液中后形态分为溶解态、可洗脱和不可洗脱态,可洗脱的Cr能够向不可洗脱态转变.Cr(VI)对活性污泥硝化活性的抑制程度随着Cr(VI)浓度的增大而提高.静态试验中,1、3、5、10和30 mg · L-1 Cr(VI)对氨氮平均降解速率的抑制率分别为5.25%、9.80%、10.41%、17.54%和21.38%.Cr(VI)对微生物的抑制作用大小是:氨氧化菌 >亚硝酸盐氧化菌 >异养菌.模型分析发现,Cr(VI)对氨氧化菌和异养菌比耗氧速率的抑制符合Haldane动力学模型,属于非竞争性抑制.冲击试验表明Cr对硝化等的抑制主要是不可洗脱的Cr造成的,抑制效果的出现具有滞后性. 相似文献
17.
谷壳的差热红外扫描电镜分析及对铜铅离子的生物吸附研究 总被引:6,自引:0,他引:6
用差热分析(DTG-DTA)、红外光谱(FTIR)、扫描电镜(SEM/EDS)等方法对谷壳的质量随温度上升而变化的情况、表面的官能团、表面形态及主要元素构成等进行了分析,并研究了谷壳对水溶液中Cu2 、pb2 的生物吸附作用.加热170℃时谷壳质量损失约6%,至170~290℃时质量损失约45%,至500℃时质量仅余约11%.在320℃、440℃分别有2个放热峰.谷壳的红外吸收光谱图主要由碳水化合物如木质素、纤维素等的吸收带组成.红外光谱分析表明,1735 cm-1和1615 cm-1处的吸收峰为不同C=O的伸缩振动峰;1515 cm-1处为苯环的骨架振动峰,而1243 cm-1处是苯羟基中C-O的伸缩振动峰.1456 cm-1处的吸收峰为CH3-和CH2-的弯曲振动峰,1374 cm-1处是甲基的弯曲振动峰.SEM/EDS分析表明,谷壳表面粗糙,且主要由碳氧硅铝元素构成.结果表明,吸附时间、溶液pH、吸附剂用量、金属离子初始浓度及Na 和Ca2 离子对吸附均有影响.谷壳对Cu2 、Pb2 的吸附在30min基本达到平衡,在pH为5左右吸附效果较好,Ca2 对吸附的影响比Na 严重.随初始浓度的增加,吸附量增大,且吸附可用Langmuir方程描述.在本实验条件下,谷壳对Cu2 、Pb2 的最大吸附量分别为3.46 mg·L-1、12.5mg·L-1.一种金属离子的存在能显著降低谷壳对另一种金属离子的吸附,且pb2 对Cu2 的影响较Cu2 对pb2 的影响更严重.单一体系和混合体系的实验结果表明,谷壳对单一体系中Cu2 、Pb2 的吸附能力分别大于对混合溶液中Cu2 、Pb2 的吸附能力. 相似文献
18.
改性泥炭-树脂颗粒对水溶液中酸性橙Ⅱ的吸附 总被引:1,自引:1,他引:1
通过批量实验研究了改性泥炭-树脂颗粒对水溶液中酸性橙Ⅱ的吸附特性.Langmuir和Freundlich吸附等温方程被用于分析吸附等温数据,准一级动力学模型、准二级动力学模型和颗粒扩散模型被用于吸附动力学实验数据分析.结果表明,改性泥炭-树脂颗粒对水溶液中酸性橙Ⅱ的吸附过程符合Langmuir和Freundlich吸附等温方程,最大吸附量达到71.43 mg·g-1;颗粒扩散模型能够很好地描述改性泥炭-树脂颗粒对水溶液中酸性橙Ⅱ的吸附动力学过程,水溶液中染料的初始浓度、颗粒直径、颗粒量及搅拌速度对吸附速率均产生一定的影响.改性泥炭-树脂颗粒对水溶液中酸性橙Ⅱ的吸附作用主要发生在颗粒的外表面. 相似文献
19.
污泥活性炭对染料的吸附动力学研究 总被引:34,自引:2,他引:34
以城市污水处理厂脱水污泥作为原料,采用化学活化法(ZnCl2作为活化剂)制得污泥活性炭,全面研究了污泥活性炭对活性艳红K-2BP、酸性大红GR和直接紫N这3种染料的吸附动力学行为.结果表明,污泥活性炭可以有效地吸附染料,实现污泥的资源化;3种染料的平衡吸附量qe均随着染料初始浓度和温度的增大而增大,相同条件下平衡吸附量qe的大小顺序为:酸性大红GR>活性艳红K-2BP>直接紫N;伪二级动力学模型能够很好地描述3种染料在污泥活性炭上的吸附动力学行为;对于活性艳红K-2BP和直接紫N,颗粒内扩散过程是该吸附速率的控制步骤,但不是唯一的速率控制步骤,吸附速率同时还受颗粒外扩散过程的控制,而对于酸性大红GR,颗粒内扩散过程不是吸附速率的控制步骤;污泥活性炭对3种染料的吸附是一个吸热过程,吸附活化能较小,主要为物理吸附过程. 相似文献
20.
结合生物作用机理,提出缺氧生物吸附活性污泥法生物脱氮(ABSAS工艺)工艺,在小试的基础上,进行了中试研究。结果表明,通过强化缺氧吸附作用可提高反硝化作用速率,在仅有污泥回流而无硝化混合液回流的前提下,TN去除仍可达60%~80%。在冬季(8~13℃)进水NH+4-N60mg/L左右、HRT10小时时,NH+4-N去除率达88%以上,出水小于15mg/L。此工艺具有很好的工业应用前景,可在设备投资增加不大的情况下,实现将传统活性污泥法工艺改造为具有生物脱氮功能的工艺 相似文献