废弃干果壳粉吸附亚甲基蓝模拟印染废水试验研究

采用巴旦杏、核桃、杏壳粉对亚甲基蓝质量浓度为10mg/L的模拟废水进行了静态吸附试验.结果表明,在吸附剂种类、吸附剂用量和吸附时间3个因素中,吸附剂种类对亚甲基蓝吸附量影响最大,巴旦杏壳粉对亚甲基蓝吸附量最佳,亚甲基蓝去除率可达90.49%.二级动力学模型能较好地描述巴旦杏壳粉对模拟染料废水中亚甲基蓝大分子的吸附动力学过程.随着温度的升高,巴旦杏壳粉对亚甲基蓝的吸附量增加.对吸附等温线相关系数进行拟合,表明Freundlich吸附等温线方程能较好地反映吸附过程.     

热活化过硫酸钠处理亚甲基蓝模拟染料废水研究

采用热活化过硫酸钠技术处理亚甲基蓝模拟染料废水,考察了反应温度、过硫酸钠用量、溶液pH以及溶液离子强度对亚甲基蓝模拟染料废水脱色效果的影响.研究结果表明:升高反应温度和增大过硫酸钠的质量浓度会提高亚甲基蓝的去除率,80℃,n(过硫酸钠)∶n(亚甲基蓝)=50∶1时,反应3 h,亚甲基蓝去除率可达90%以上;在pH=2~10时,溶液pH越低,亚甲基蓝的去除效率越高,碱性条件会明显地抑制亚甲基蓝的去除;溶液离子强度影响反应体系的反应速率,离子强度增大(0.11~0.25 mol/L)会降低过硫酸钠氧化亚甲基蓝的反应速率.     

CnMImBr类离子液体与染料的相互作用

以N-甲基咪唑为原料合成了CnMImBr（H=8，12，14，16）四种溴化-1-烷基-3-甲基咪唑类离子液体，采用红外光谱和电导率分析法对其结构性能进行了表征，并对其与酸性橙Ⅱ和亚甲基蓝的相互作用进行了探讨。研究表明，这四种离子液体均具有表面活性，其临界胶束浓度随着烷基碳链上碳原子数的增加而降低；C12 MImBr、C14MImBr和C16MImBr在不同浓度范围内与酸性橙Ⅱ存在着不同的相互作用方式，而此四种离子液体使亚甲基蓝聚集程度略有增加。     

亚甲基蓝溶液标准曲线的分析

亚甲基蓝常常被作为染料行业的模拟有机污染物进行吸附去除处理的研究.亚甲基蓝溶液的质量浓度是研究过程中必测的参数.大部分科研工作者都是用紫外-可见分光光度计测定亚甲基蓝溶液吸光度,在测试前先建立亚甲基蓝溶液的标准曲线,然后用标准曲线计算其质量浓度,因此实验对标准曲线做了详细的分析.结果发现,吸光度和质量浓度在不同范围内遵...     

凹凸棒土与活性炭对水溶性染料的吸附研究

研究了凹凸棒土与活性炭对水溶性染料亚甲基蓝和弱酸艳蓝RAW的吸附作用，考察了各种因素对吸附效果的影响．结果表明：升高温度、增加pH值均有利于凹凸棒土对亚甲基蓝的吸附，不利于其对弱酸艳蓝RAW的吸附,温度升高，活性炭对2种染液的脱色率均有提高；酸性条件有利于活性炭对亚甲基蓝的吸附，而碱性条件有利于其对弱酸艳蓝RAW的吸附．达到同等处理效果，凹凸棒土用量明显少于活性炭,除活性染料外，凹凸棒土对其他染料的脱色性能均优于活性炭．     

微硅粉对亚甲基蓝吸附性能的研究

文章研究了微硅粉对浓度亚甲基蓝的吸附性能。结果表明,微硅粉对亚甲基蓝的最大吸附量达21.2mg/g,其吸附规律较好的符合langmuir吸附等温式。随着时间的增加和温度升高,吸附率增加。微硅粉对亚甲基蓝的吸收速率符合准二级吸附动力学方程,PH值对微硅粉吸附性能影响较大,碱性越大吸附性能越好。在600℃高温下再生2h后吸附率可达到94%以上。     

酚醛基活性炭纤维的制备及其对亚甲基蓝染料溶液的吸附性能研究

以酚醛纤维为原料,采用水蒸气活化法进行物理活化,制备具有丰富微孔结构的酚醛基活性炭纤维,并以亚甲基蓝染料溶液作为吸附质,探讨吸附时间、吸附温度、染料溶液初始浓度对其吸附性能的影响,同时对其吸附平衡、吸附动力学进行研究。结果表明:酚醛基活性炭纤维对亚甲基蓝染料分子的吸附性较好,吸附时间、吸附温度及染料溶液初始浓度均对吸附性能有较大影响;吸附过程符合Langmuir吸附等温线模型和准二级动力学模型,表明酚醛基活性炭纤维对亚甲基蓝染料分子的吸附属于单分子层吸附,且吸附过程以化学吸附为主导。     

交联羧甲基玉米淀粉对水溶液中亚甲基蓝吸附特性的研究

采用交联羧甲基玉米淀粉吸附剂对模拟废水中的亚甲基蓝进行吸附性能研究.考察了吸附剂用量、pH、吸附时间以及染料初始浓度等因素对亚甲基蓝吸附效果的影响,并进行交联羧甲基玉米淀粉去除亚甲基蓝染料的吸附等温线拟合及吸附动力学研究.结果表明,当亚甲基蓝初始浓度100mg/L、pH6.0、交联羧甲基玉米淀粉用量0.2g、吸附温度25℃以及吸附时间60min时,亚甲基蓝吸附率可达95.66％;25℃下交联羧甲基玉米淀粉理论饱和吸附量为80mg/g;染料吸附等温线符合Langmuir模式(R2＞0.99);吸附过程符合准一级和二级反应动力学方程(R2＞0.99).     

角蛋白/酚磺酸缩合物复合材料对亚甲基蓝的吸附研究

在皮革的生产加工过程中,角蛋白未能得到充分利用便被处置,造成了一定的资源浪费.通过溶液共混法制备了角蛋白/酚磺酸缩合物复合材料,并考察其对亚甲基蓝的吸附性能.研究结果表明:复合材料对亚甲基蓝的吸附量随pH值的上升而上升,对400 mg/L的亚甲基蓝最佳吸附条件是pH值为10,复合材料使用量为2.0 g/L,吸附温度50...     

有机溶剂对液体活性染料分散和水解稳定性影响的模拟研究

为探究液体活性染料体系中有机溶剂对活性染料储存稳定性的影响机制,基于分子动力学模拟,考察了4种有机溶剂对高浓度C.I.活性蓝176聚集以及水解稳定性的影响,并进行实验验证。结果表明:不同有机溶剂对活性染料分散及水解效果影响的差异,与有机溶剂在染料分子聚集有效区域以及染料水解基团周围的分布有关,二者间相互作用的强弱决定了染料的储存稳定性;N-甲基吡咯烷酮体系中,4种有机溶剂的72个染料分子中有31个染料分子可以单分子形式存在,其对C.I.活性蓝176的分散稳定性最佳;己内酰胺在染料水解基团氯原子周围的分布更多,其对抑制液态活性染料的水解效果最好。     

低代数聚酰胺-胺树形分子在棉纤维染色中的应用研究

聚酰胺-胺树形分子作前处理试剂对棉纤维进行直接染料上染.研究了温度、树形分子用量和代数对表面深度(K/S值)的影响.结果表明,PAMAM树形分子可以有效地促进直接染料的上染,增加上染率;对有些染料它可以有超过NaCl为促染剂的表面深度.     

Dendritic chelating agents. 2. U(VI) binding to poly(amidoamine) and poly(propyleneimine) dendrimers in aqueous solutions

Chelating agents are widely employed in many separation processes used to recover uranyl [U(VI)] from contaminated aqueous solutions. This article describes an experimental investigation of the binding of U(VI) to poly(amidoamine) [PAMAM] and poly(propyleneimine) [PPI] dendrimers in aqueous solutions. We combine fluorescence spectroscopy with bench scale ultrafiltration experiments to measure the extent of binding and fractional binding of U(VI) in aqueous solutions of these dendrimers as a function of (i) metal-ion dendrimer loading, (ii) dendrimer generation, (iii) dendrimer core and terminal group chemistry, and (iv) solution pH and competing ligands (NO3-, PO4(3-), CO3(2-), and Cl-). The overall results of this study suggest that uranyl binding to PAMAM and PPI dendrimers in aqueous solutions involves the coordination of the UO2(2+) ions with the dendrimer amine, amide, and carboxylic groups. We find significant binding of U(VI) to PAMAM dendrimers in (i) acidic solutions containing up to 1.0 M HNO3 and H3PO4 and (ii) in basic solutions containing up to 0.5 M Na2CO3. However, no binding of U(VI) by PAMAM dendrimers is observed in aqueous solutions containing 1.0 M NaCl at pH 3.0. These results strongly suggest that PAMAM and PPI dendrimers can serve as high capacity and selective chelating ligands for U(VI) in aqueous solutions.     

Dendrimer enhanced ultrafiltration. 1. Recovery of Cu(II) from aqueous solutions using PAMAM dendrimers with ethylene diamine core and terminal NH2 groups

This article discusses the feasibility of using dendrimer enhanced ultrafiltration (DEUF)to recover Cu(II) from aqueous solutions. Building upon the results of fundamental investigations of Cu(II) binding to PAMAM dendrimers with ethylenediamine (EDA) core and terminal NH2 groups, we combine (i) dead-end ultrafiltration (UF) experiments with (ii) atomic force microscopy (AFM) characterization of membrane fouling to assess the feasibility of using DEUF to recover Cu(II) from aqueous solutions. On a mass basis, the Cu(II) binding capacities of the EDA core PAMAM dendrimers are much larger and more sensitive to solution pH than those of linear polymers with amine groups. The dendrimer-Cu(II) complexes can be efficiently separated from aqueous solutions by ultrafiltration. The metal ion laden dendrimers can be regenerated by decreasing the solution pH to 4.0; thus enabling the recovery of the bound Cu(II) ions and recycling of the dendrimers. The UF measurements and AFM characterization studies show that EDA core PAMAM dendrimers with terminal NH2 groups have very lowtendency to foul the commercially available regenerated cellulose (RC) membranes evaluated in this study. The overall results of these experiments suggest that DEUF is a promising process for recovering metal ions such as Cu(II) from aqueous solutions.     

阴离子树枝状聚酰胺-胺在有机微粒助留助滤体系中的应用

通过碱性水解将端酯基的半代树枝状聚酰胺-胺(Gn.5PAMAM)改性为外层基团为羧酸钠的阴离子树枝状聚酰胺-胺(A-Gn.5PAMAM),并通过红外光谱进行了结构表征。将A-Gn.5PAMAM作为有机阴离子微粒组分与星形阳离子聚丙烯酰胺(S-CPAM)及阳离子聚丙烯酰胺(CPAM)组成有机微粒助留助滤体系,系统地研究了该有机微粒体系对漂白旧报纸脱墨浆的助留助滤效果。结果表明,S-CPAM(CPAM)-(A-Gn.5PAMAM)有机微粒体系对纸料具有较好的助留助滤作用效果;高代数的A-Gn.5PAMAM对纸料小絮块的絮聚能力优于低代数产物;该有机微粒助留助留体系可以适应较宽的pH值范围,且抵抗高剪切作用的能力较强。研究同时表明,A-Gn.5PAMAM有机阴离子微粒与膨润土无机阴离子微粒具有很好的协同作用。     

PAMAM型树枝状化合物的合成及其在皮革工业中的应用

介绍了近年来PAMAM型树枝状化合物的合成及其在皮革工业上的应用,并对它的应用前景进行了展望。     

Removal of copper from contaminated soil by use of poly(amidoamine) dendrimers

This study characterizes poly(amidoamine) (PAMAM) dendrimers of various generations and terminal functional groups for removal of copper(II) in a sandy soil. Effects of dendrimer dose, generation number, pH, terminal functional groups, and ionic strength on the removal efficiency were investigated through a series of column tests. Over 90% of copper initially sorbed in the soil was removed by use of approximately 66 bed volumes of 0.10% (w/w) of a generation 4.5 dendrimer with carboxylate terminal groups at pH 6.0. On the basis of equal equivalent dose, dendrimers of lower generation removed more copper. Lowering pH enhanced copper removal for all dendrimers tested. In contrast, types of terminal groups (carboxylate, amine, or hydroxyl) showed a modest effect on the removal efficiency. Results from a sequential extraction procedure suggested that dendrimers removed primarily exchangeable and carbonate-bound copper. The residual copper in treated soil is predominantly bound with soil organic matter (SOM), which is much less available physical-chemically or biologically. Spent dendrimers were recovered through nanofiltration with a commercially available nanofilter. Upon acid regeneration, recovered dendrimers were reused and performed as well as the virgin dendrimers. The dendrimers may be used as reusable, high-capacity extracting agents for in situ removal of heavy metals from contaminated soils.     

Enhancement of biological reduction of hematite by electron shuttling and Fe(II) complexation

Natural organic matter (NOM) enhancement of the biological reduction of hematite (alpha-Fe2O3) by the dissimilatory iron-reducing bacterium Shewanella putrefaciens strain CN32 was investigated under nongrowth conditions designed to minimize precipitation of biogenic Fe(II). Hydrogen served as the electron donor. Anthraquinone-2,6-disulfonate (AQDS), methyl viologen, and methylene blue [quinones with an Ew0 (pH 7) of 0.011 V or less], ferrozine [a strong Fe(II) complexing agent], and characterized aquatic NOM (Georgetown NOM or Suwannee River fulvic acid) enhanced bioreduction in 5-day experiments whereas 1,4-benzoquinone (Ew0 value = 0.280 V) did not. A linear relationship existed between total Fe(II) produced and concentrations of ferrozine or NOM but not quinones, except in the case of methylene blue. Such a linear relationship between Fe(II) and methylene blue concentrations could be due to the systems being far undersaturated with respect to methylene blue or the loss of the thermodynamic driving force. A constant concentration of AQDS and variable concentrations of ferrozine produced a linear relationship between total Fe(II) produced and the concentration of ferrozine. Enhancement effects of both AQDS and ferrozine were additive. NOM may serve as both an electron shuttle and an Fe(II) complexant; however, the concentration dependence of hematite reduction with NOM was more similar to ferrozine than quinones. NOM likely enhances hematite reduction initially by electron shuttling and then further by Fe(II) complexation, which prevents Fe(II) sorption to hematite and cell surfaces.     

PAMAM改性海藻酸钙纤维的染色动力学

采用直接湖蓝5B研究树状大分子PAMAM改性海藻酸钙纤维的染色动力学,包括上染速率曲线、半染时间、平衡上染百分率、比染色速率常数和扩散系数。与未改性的海藻酸钙纤维相比,PAMAM改性海藻酸钙纤维的染色性能大大改善,且改善程度与纤维中PAMAM的含量成正比。随着改性海藻酸钙纤维中PAMAM含量的增加和染色温度的升高,染料的平衡上染百分率提高,半染时间缩短,比染色速率常数增大,扩散系数增加,海藻酸钙纤维的染色性能得到改善。     

香蕉叶活性炭的制备及其对亚甲基蓝的吸附性能

以香蕉叶废渣为原料,利用KOH活化制备香蕉叶活性炭(BLAC)以吸附废水中的亚甲基蓝.采用SEM、BET、XRD对BLAC进行表征.结果 表明,BLAC的BET比表面积达1257.852 m2/g,总孔体积达0.718 m3/g.BLAC用于模拟亚甲基蓝废水的吸附研究表明,303 K时BLAC对亚甲基蓝的最大吸附量为5...