微波法制备污泥吸附剂的性能优化研究

通过向污泥中添加吸收微波能的物质实现了微波热解法制备污泥吸附剂,并考察了不同制备条件对污泥吸附剂性能的影响.结果表明,当污泥用量为35 g时,微波法制备污泥吸附剂的最佳务件:微波功率为1.2 kW、辐照时间为10 min、微波能吸收物质的用量为10 g,制得的污泥吸附剂的碘吸附值达585.95 mg/g.采用扫描电镜分析污泥吸附剂的表观结构可知,适宜的微波辐射通过有效热解污泥中的有机质可形成以炭骨架为主体的污泥吸附剂,该吸附剂可有效吸附酸、碱染料,但吸附量与商业活性炭仍存在一定差距.     

吸附法去除废水中染料罗丹明B的研究

针对废水溶液中的污染物罗丹明B,先在碱性条件下制备一种多孔二氧化硅复合材料(PSCs),探究该材料对水溶液中阳离子染料罗丹明B(RhB)的吸附性能,对吸附过程进行了动力学模型及等温线模型的研究,并推断吸附机理。结果表明,溶液pH值在3.0～7.0范围内,PSCs对罗丹明B的吸附效果良好,染料初始浓度为10 mg/L时,PSC-1对RhB的吸附率可达97.9%,染料初始浓度为50 mg/L时,PSC-1对RhB的吸附量为45.3 mg/g。PSCs对罗丹明B的吸附符合准二级动力学模型及Freundlich模型,PSC-3对罗丹明B的吸附也符合Langmuir模型,其对RhB的吸附主要通过静电作用及氢键作用实现。实验结果可为染料废水的处理提供理论依据和数据支持。     

新型介孔脱色剂的制备及脱色性能研究

采用挥发诱导自组装技术，以乙醇为溶剂、四甲基氢氧化铵（TMAOH）为结构导向剂，合成了介孔孔径为6．1nm的新型脱色剂来处理偶氮染料废水。选用活性艳红X-3B和酸性橙Ⅱ为目标污染物，考察了初始pH值、振荡时间和染料初始浓度对介孔脱色剂的性能影响。结果表明，强酸性环境（pH≤2）利于吸附反应的发生，且该脱色剂达到吸附平衡的时间短。在温度为25℃、初始pH值为2、振荡时间为1h、振荡频率为150r／min、脱色剂投加量为1g／L的条件下，对两种染料的饱和吸附量分别可达402．3mg／g和267．2mg／g，吸附行为符合Langmuir模型。     

酸热改性凹凸棒石粘土对低硫汽油的脱硫效果研究

通过浸渍法制备改性凹凸棒石粘土汽油脱硫剂.用浓硫酸对产自甘肃临泽的凹凸棒石粘土进行酸改性和热活化,以改性后的凹凸棒石粘土为吸附剂,达到了对汽油进行吸附脱硫的目的.采用正交试验考察制备脱硫剂和吸附脱硫的最佳工艺条件.根据正交试验分析得到确定最佳试验工艺路线为A3B3C2D2E3,即酸化凹凸棒石粘土的硫酸浓度为2mol/L、热改性温度为90℃、吸附时间60min.最佳吸附脱硫工艺为脱硫剂用量4g/40mL、吸附温度为40℃、吸附时间为60min.凹凸棒石粘土经过改性后脱硫率明显提升,硫含量的质量分数从280μg/g降到54.43μg/g,脱硫率达到80.56％.     

甲基丙烯酸丁酯-甲基丙烯酸羟乙酯共聚物/聚对苯二甲酸乙二酯/CaCO_3复合树脂制备及其性能研究

以甲基丙烯酸丁酯-甲基丙烯酸羟乙酯共聚物为基质,丙烯酸丁酯为反应性单体,过氧化苯甲酰为引发剂,采用共熔融反应挤出法将刚性的碳酸钙和聚对苯二甲酸乙二酯引入聚甲基丙烯酸酯中,制得新型复合树脂。研究复合树脂的吸油性能、耐油品溶解能力以及吸染料性能,并借助热重分析仪、差示扫描量热仪、X-射线衍射仪等仪器对复合树脂的相关结构与性能进行表征。结果表明,所有样品的吸油量均呈现先增大后减小的变化趋势,且酸处理后样品的吸油量明显增加;经60min动态循环吸附,油水混合物中的油几乎被完全去除;碱处理前样品对阳离子蓝染料的吸收效率极低,而碱处理后样品具备了吸附阳离子蓝染料的能力,特别是经360min碱处理后,样品对阳离子蓝染料的吸收效率接近于100%。     

微波诱导催化氧化降解活性艳红的研究

文中采用微波诱导氧化工艺对活性艳红水溶液的降解进行了初步研究.实验分别考察了活性艳红水溶液不同初始浓度、催化剂投加量、H2O2投加量、微波辐照时间和pH等因素对活性艳红降解效果的影响.结果表明:取100mL浓度为300 mg/L活性艳红水溶液加入12 g改性氧化铝催化剂,辐照时间1.5 min,H2O2用量为4 mL,pH为6.0的条件下,活性艳红水溶液的褪色率达98.2%,CODσ去除率达84.5%.微波降解活性艳红具有降解速率快、成本低、没有中间产物生成和不会造成二次污染等优点,适合于大规模治理染料废水.     

二氧化钛-二氧化硅复合材料对亚甲基蓝的吸附与光降解

制备了一种具有多孔结构的二氧化钛-二氧化硅复合材料,采用其吸附并光催化降解水中的染料。结果表明,钛掺杂复合材料具有良好的吸附性能和光催化活性,吸附亚甲基蓝60min后达到吸附平衡,对染料的去除率约为99%。吸附过程符合准二级动力学模型和Freundlich等温吸附模型。吸附饱和后的材料在紫外光照下能进一步去除染料,且再生8次后对染料的去除率仍保持在90%以上。     

镧/钛共掺杂硅基材料的制备及对亚甲基蓝的去除

制备了一种镧/钛共掺杂的硅基材料(SM-La-Ti),探究了其对亚甲基蓝溶液的吸附和光催化能力。结果表明,p H值在7～12时材料的吸附和光催化性能良好,吸附反应在前15min进行迅速,并在90 min达到平衡,符合准二级动力学方程和Fruendich方程。该材料的光催化性能良好,吸附完成后仍能通过光催化进一步去除亚甲基蓝。     

改性石英砂吸附水中四环素的机制研究

通过使用Piranha溶液和KH-550溶液对普通石英砂(NAT)进行改性处理,得到亲水改性石英砂(HYL)和疏水改性石英砂(HYB),对3种石英砂进行表面性质表征并考察其吸附四环素的性能和影响因素。结果表明,HYL和HYB的比表面积均大于NAT,且亲、疏水性得到改善。HYL、HYB和NAT对四环素的饱和吸附量分别为25. 60、7. 67和11. 94 mg/kg。伪一级动力学模型和伪二级动力学模型对3种石英砂吸附四环素过程的拟合程度均较好(R~2 0. 97); Langmuir和Freundlich吸附等温模型拟合程度较好(R~2 0. 97),Tempkin模型拟合相关系数R~2=0. 74～0. 84。HYL在pH值=6. 0且无阳离子作用下吸附效果最佳; HYB在pH值=10. 0时吸附效果较好,且Ca~(2+)的存在使吸附量大量增加; NAT在p H值=10. 0、无阳离子作用下吸附效果最佳。经分析,HYL吸附四环素主要为化学吸附并伴有一定程度的静电作用,HYB主要依靠表面吸附并带有离子交换作用,NAT主要以化学吸附为主。     

双硫脲基螯合纤维对Hg~(2+)的吸附性能研究

在N,N′-羰基二咪唑(CDI)的偶联作用下,将双硫脲(DTA)修饰在聚丙烯酸接枝聚丙烯(PP-gAA)纤维表面,得到双硫脲基螯合纤维(PP-g-AA-DTA),并探讨了该螯合纤维对Hg~(2+)的吸附性能。采用傅里叶红外光谱、X射线光电子能谱、扫描电子显微镜等研究了螯合纤维结构、不同吸附条件对Hg~(2+)吸附的影响以及选择性吸附特性。结果表明准二级动力学模型和Langmuir模型可以很好地描述吸附过程,饱和吸附容量为66.40mg/g。该新型螯合纤维可望应用于水体中Hg~(2+)的去除领域。     

Preparation of P(St-BA-VBT)/dye Colored Nanoparticles

P(St-BA-VBT)/dye colored nanoparticles were prepared by staining P(Styrene-Butyl Acrylate-Vinyl Benzyl Trimethylammonium chloride) nanoparticles synthesized by soap free cationic emulsion polymerization with reactive dyes. The effects of reactive dyes dosage, dyeing temperature and time on amounts of dyes adsorbed on the nanoparticles were analysed. Results showed that when Reactive Red 195 dosage was5.25%, the adsorption amounts of dyes on the nanoparticles reached a maximum value of 18.64 mg/g at 65℃ for 90 min.     

复合混凝剂PTA-CPAM的形貌结构与净水性能

以聚合氯化铝(PAC)、四氯化钛(TiCl_4)、阳离子聚丙烯酰胺(CPAM)为原料成功制备无机-有机复合混凝剂聚钛氯化铝-阳离子聚丙烯酰胺(PTA-CPAM),采用红外光谱(IR)、扫描电镜(SEM)、能谱分析(EDS)与差热热重(TG-DTA)对产物的结构、组成及热稳定性进行分析。此外,对PTA-CPAM的混凝性能进行研究。结果表明:当m(CPAM)/m(PTA)=0.4、PTA-CPAM投加量为9.0mg/L、pH为9.0的条件下,混凝剂的净水效果最优,且PTA-CPAM对不同初始浊度的水样都有较优的除浊能力;协同增效作用使PTA-CPAM具备更强的吸附电中和与吸附架桥网捕能力,表现出优异的除浊性能。     

净水型赤泥-矿渣基地聚合物透水混凝土的研究

研究了赤泥掺量、碱激发剂模数及碱当量、集料空隙率等对赤泥-矿渣基地聚合物透水混凝土(RSGPC)力学性能、透水性能和重金属吸附性能的影响规律,采用X射线衍射(XRD)、扫描电子显微镜(SEM)和X射线能谱仪(EDS)等微观测试手段,探讨了RSGPC对溶液中重金属离子的吸附机理及重金属离子在RSGPC浆体表面的分布规律.结果表明:RSGPC对重金属离子的吸附性能随赤泥掺量的增加和集料空隙率的降低而增加,而受碱激发剂模数及碱当量的影响不大; RSGPC对重金属离子的吸附作用主要是未水化赤泥颗粒、地聚合物凝胶以及低钙硅比C-S-H凝胶的吸附作用,同时还与透水混凝土表面浆体和溶液中重金属离子的接触时间有关;提高浆体自身的力学性能与吸附性能,是协调透水混凝土强度、透水、净水三者之间矛盾的有效途径.     

有机硅氧烷改性苯丙乳液涂料

在苯乙烯-丙烯酸乳液聚合过程中，加入一定量的有机硅氧烷进行共聚，制得建筑涂料。研究了反应温度、时间、乳化剂用量等因素对反应进程，乳液的稳定性及涂料性能的影响。     

纳米TiO2-AC负载膜光催化降解偶氮染料

以钛酸四丁酯和活性炭为主要原料，采用溶胶-凝胶-浸渍法制备纳米TiO2-AC负载膜催化剂，并借助流化床反应器分别对两种典型的偶氮类染料橙黄C、活性艳红X-3B模拟废水进行了UV光降解、暗态吸附及光催化降解研究，探讨了pH值、外加氧化剂对光催化去除率的影响，同时对催化剂进行回收再生利用试验。结果表明：纳米TiO2-AC负载膜具有很好的光催化活性、吸附特性及可再生性，两种染料1h的光催化降解率最高分别可达99．71％和97．12％。反应过程中固、液、气三相能够有效分离，实现了反应与分离的一体化。     

Kinetics of adsorption of water-soluble dyes on activated carbons

We have investigated the kinetics of adsorption of anionic (methyl orange, acid orange, congo red) and cationic (methylene-blue, crystalline violet) dyes from aqueous solutions on activated carbons BAU-A, Filtrasorb 300, and Aquasorb 2000. It has been found that the kinetic curves of adsorption of the dyes may have a smooth or stepwise look depending on the nature of a dye or adsorbent. We have considered the possibility of using kinetic equations of the pseudofirst and pseudosecond order for describing the adsorption process.     

Retention of organophosphorous insecticides on a calcareous soil modified by organic amendments and a surfactant

Pesticides may affect soil quality since they are applied either directly to the soil or transported from the treated crops. Although the soil is able to partially retain environmental contaminants, the use of organic amendments, such as sewage sludge, peat or surfactants, may increase the retention in the upper soil layers, where the contaminants can be degraded and thus diminish their environmental fate. The effect of adding sewage sludge, peat and humic acids, together with a cationic surfactant to the soil, on the adsorption and desorption of organophosphorous insecticides has been studied. The results indicate that humic acids induce an adsorption increment of the pesticides, while peat and sewage sludge do not significantly affect pesticide adsorption at the dosage applied. The use of a cationic surfactant considerably enhances the insecticide retention. The increase was highest for the combined application of the surfactant and the humic acids. Desorption isotherms are inversely related to the adsorption behaviour, being higher for only soil, lower for soil added with carbon-rich amendments, and drastically reduced when the cationic surfactant is present. Concerning the insecticides, adsorption and desorption are related to their physicochemical properties.     

Removal of dyes from aqueous solution using fly ash and red mud

Fly ash and red mud have been employed as adsorbents for the removal of a typical basic dye, methylene blue, from aqueous solution. Heat treatment and chemical treatment have also been applied to the as-received fly ash and red mud samples. It is found that fly ash generally shows higher adsorption capacity than red mud. The raw fly ash and red mud show adsorption capacity at 1.4 x 10(-5) and 7.8 x 10(-6) mol/g, respectively. Heat treatment reduces the adsorption capacity for both fly ash and red mud but acid treatment by HNO(3) induces a different effect on fly ash and red mud. Nitric acid treatment results in an increase in adsorption capacity of fly ash (2.4 x 10(-5) mol/g) while it decreases the adsorption capacity for red mud (3.2 x 10(-6) mol/g). The adsorption data have been analysed using Langmuir, Freundlich and Redlich-Peterson isotherms. The results indicate that the Redlich-Peterson model provides the best correlation of the experimental data. Isotherms have also been used to obtain the thermodynamic parameters such as free energy, enthalpy and entropy of adsorption. For fly ash and red mud, adsorption of methylene blue is endothermic reaction with DeltaH(0) at 76.1 and 10.8 kJ/mol, respectively.     

Magnetic powder MnO-Fe2O3 composite--a novel material for the removal of azo-dye from water

Fine powder adsorbents or catalysts often show better adsorptive or catalytic properties, but they encounter the difficulties of separation and recovery in application. In this study, four inexpensive magnetic powder MnO-Fe2O3 composites used as adsorbent-catalyst materials were prepared and characterized. These materials could be recovered efficiently by a magnetic separation method. Their adsorptive properties for the removal of an azo-dye, acid red B (ARB), from water and the regeneration of adsorbents containing ARB by catalytic combustion was studied. These powder adsorbents showed excellent adsorption towards ARB under acidic conditions. A very fast adsorption rate was observed and could be well described by a pseudo-second-order kinetics model. The adsorption capacity increased with increasing Fe content and surface area of the adsorbent, and the highest adsorption capacity of 105.3 mg/g was obtained at pH 3.5. The adsorption was not affected by the presence of Cl-, but was significantly affected by SO4(2-). The adsorbent containing ARB can be regenerated by catalytic combustion of adsorbed ARB at 400 degrees C in air. Laboratory experiments demonstrated that this material is reusable.     

负载型纳米TiO_2光催化降解酸性红B的研究

为解决传统纳米TiO2光催化氧化工艺催化剂不易分离和载体的比表面积较小、悬浮性差的问题,将纳米TiO2负载在聚丙烯多面球上制备了负载型TiO2光催化剂.利用XRD和氮气吸附法表征了该催化剂的结构特性,并采用其降解酸性红B,考察了初始浓度、曝气量、pH值、H2O2投加量、自由基清除剂及多面球的比表面积等对降解效果的影响.结果表明,偶联剂法制备的TiO2薄膜晶相单一(锐钛矿型),晶体粒度较小,比表面积较大;脱色率会随着酸性红B溶液初始浓度的升高和自由基清除剂(乙醇)的加入而下降,提高溶解氧浓度、增加聚丙烯多面球的比表面积以及酸性条件(pH=3.26时效果最佳)都有利于提高脱色率;投加H2O2也能提高脱色率,但当投加量增至0.5 mg/L后效果不再明显;酸性红B的光催化降解遵循一级反应动力学方程.