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1.
酸改性凹凸棒土对含酚模拟废水的吸附性能研究   总被引:1,自引:0,他引:1  
将HF、HNO3、H2SO4、HCl酸化改性的凹凸棒土,用于含苯酚的模拟废水进行吸附处理研究.考察了凹凸棒土的用量、震荡时间、pH值以及不同改性剂等因素对吸附性能的影响.结果表明,改性的凹凸棒土处理废水的最佳工艺条件为:投入量0.400 g,震荡时间30 min,水样pH 14.0,对废水中苯酚的吸附能力最强;经酸改性后凹凸棒土的吸附能力较原土均有较大的提高,并且酸种类对其吸附率也有一定的影响,吸附能力按HNO3>HCl>H2SO4>HF次序递减,对可能原因进行了初步探讨.  相似文献   

2.
以研制高效吸附除磷填料为目的,以凹凸棒土为试验对象,比较了不同改性条件制备的改性凹凸棒土吸附除磷效果.结果表明:热改性、酸改性、碱改性、盐改性和稀土元素改性均能提高凹凸棒土除磷效果,镧改性凹凸棒土的除磷效果相对最优;优化后的热-镧复合改性凹凸棒土填料的烧结温度为500—600℃,烧结时间为3—4h,凹凸棒土、核桃砂颗粒、硅酸钠、氯化镧配比为5∶2∶2∶1,填料粒径大小为10—12mm;通过Langmuir方程拟合其最大磷吸附量为1.733mg·g~(-1),实际测得最大磷吸附量为2.316mg·g~(-1).  相似文献   

3.
改性凹凸棒土处理染化废水研究   总被引:29,自引:0,他引:29  
该文讨论了凹凸棒土的改性方法,利用改性凹凸棒土对染化废水进行了吸附脱色性能研究,考察了改性方法,pH值、凹凸棒土投加量、吸附时间等因素的影响。结果表明:改性凹凸棒土对染化废水CODcr和色度有较好的去除能力,CODcr去除率可达80%,脱色率达95%以上,该吸附剂的静态吸附行为符合Freundich吸附等温式。本研究对对凹凸棒土的应用开发提供了有价值的实验数据。  相似文献   

4.
有机改性凹凸棒土吸附微污染水中苯酚的试验研究   总被引:14,自引:3,他引:11  
研究了用聚二甲基二烯丙基氯化铵(PDMDAAC)改性凹凸棒土对微污染水中苯酚的吸附性能、影响因素及其再生后吸附效果.结果表明:PDMDAAC改性凹凸棒土对微污染水中苯酚具有较强的吸附能力,在pH=6~8、苯酚浓度为10 mg/L、投加量为40 g/L、吸附时间40 min的条件下,吸附去除率达89%;改性后的凹凸棒土可用碱进行再生,再生后对苯酚的吸附能力没有明显下降;改性凹凸棒土的静态吸附行为符合Freundlich吸附等温方程.  相似文献   

5.
以苏皖地区特色天然矿物资源凹凸棒土作为吸附剂,研究热活化温度和吸附反应温度对凹凸棒土吸附脱汞性能的影响,并利用N a2S,F e C l3,C u C l2,H2O 2和单质硫对凹凸棒土吸附剂进行化学改性,研究改性凹凸棒土吸附剂的脱汞能力。研究结果表明:经1 2 0℃和1 6 0℃热活化的凹凸棒土吸附脱汞性能有一定程度的提高,而经2 0 0℃和2 4 0℃热活化的凹凸棒土吸附脱汞性能则呈现下降趋势;吸附反应温度的提高有利于凹凸棒土对单质汞的吸附脱除;此外,经单质硫、C u C l2和F e C l3改性的凹凸棒土脱汞能力大为提高。  相似文献   

6.
以凹凸棒土为原料,制备新型铁氧化物改性凹凸棒土除锑吸附剂。探讨吸附时间、p H值、竞争离子及离子强度对吸附Sb(V)性能的影响,并对其等温吸附特征和动力学进行研究。实验结果表明:当p H=6.8,投加吸附剂的量为1 g/L时,Sb(V)在铁氧化物改性凹凸棒土上的吸附平衡时间为12 h。p H显著影响铁氧化物改性凹凸棒土对Sb(V)的吸附,吸附量随着p H的增加而降低,增加离子强度对Sb(V)的吸附有一定的促进作用。铁氧化物改性凹凸棒土对Sb(V)吸附较好符合Langmuir、Freundlich等温吸附模型和准二级动力学方程,最大吸附量可达31.79 mg/g。吸附机制主要是羟基铁的内层表面络合吸附。  相似文献   

7.
典型吸附材料对含Cs废水的吸附效能对比研究   总被引:1,自引:0,他引:1  
选取活性炭、高岭土、蒙脱土、膨润土、沸石和凹凸棒土6种典型吸附材料,通过静态批实验,探索吸附过程关键影响要素(吸附时间、初始质量浓度、溶液pH和温度)对吸附过程的影响,并结合吸附动力学模型和吸附等温线,实现6种吸附材料对含铯(Cs)废水的吸附效能对比研究. 结果表明:在相同的吸附时间内,6种吸附材料对Cs的吸附效能由高到低排序为沸石、凹凸棒土、膨润土、蒙脱土、活性炭、高岭土; 沸石对Cs的吸附率几乎不受初始质量浓度和温度的影响,其余材料适合在偏碱性环境中、30 ℃条件下去除Cs;活性炭、高岭土、蒙脱土和凹凸棒土均适合在低初始质量浓度下去除Cs;6种吸附材料对Cs的吸附过程均非单一吸附机制,而是多种吸附机制共同作用的结果. 6种典型吸附材料中,沸石、凹凸棒土与膨润土对含Cs放射性废水的处理具有明显效果,特别是沸石,吸附性能好且适应性广泛,在放射性废水的处置中具有一定应用价值.   相似文献   

8.
以凹凸棒土(Att)为基体,通过原位溶胶.凝胶浸渍的方法,制备Al2O3包覆改性凹凸棒土的凹凸棒土复合材料(产物标记为Al2O3/Att)。采用XRD、BET、SEM等分析手段对A12O3/Att的形貌进行了表征。研究表明:产物的包覆效果好、比表面大;以直接大红4B溶液为模拟废水,考察了凹凸棒土改性前后吸附性能;对凹凸棒土表面进行包覆改性,有效地改善凹凸棒土对直接大红4B吸附效果,吸附20min后,对90mg/L直接大红4B的脱色率达90%。  相似文献   

9.
以江苏盱眙凹凸棒为原料,分别选用碱土金属和硝酸为改性剂,采用浸渍法对凹凸棒进行改性处理,探讨改性凹凸棒对模拟汽油中噻吩的吸附性能的影响.结果表明:经碱土金属硝酸镁改性后的凹凸棒对噻吩的脱硫效果有一定的提高,脱硫率由原土的10.07%提高到36.38%.  相似文献   

10.
以凹凸棒土(Att)为基体,通过原位溶胶.凝胶浸渍的方法,制备Al2O3包覆改性凹凸棒土的凹凸棒土复合材料(产物标记为Al2O3/Att)。采用XRD、BET、SEM等分析手段对A12O3/Att的形貌进行了表征。研究表明:产物的包覆效果好、比表面大;以直接大红4B溶液为模拟废水,考察了凹凸棒土改性前后吸附性能;对凹凸棒土表面进行包覆改性,有效地改善凹凸棒土对直接大红4B吸附效果,吸附20min后,对90mg/L直接大红4B的脱色率达90%。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

13.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

14.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

15.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

16.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

17.
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the  相似文献   

18.
Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of  相似文献   

19.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  相似文献   

20.
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