等离子体法改性凹凸棒土吸附多氯联苯研究

运用低温等离子体改性技术将壳聚糖(CTS)接枝到凹凸棒土(ATP)表面(ATP-g-CTS),并将其应用于含2,3,3'-三氯联苯(2,3,3'-TCB)废水溶液的吸附研究。实验中应用假一级速率方程、假二级速率方程、动力学方程、Langmuir、Freundlich和D-R等动力学及热力学模型对实验数据进行模拟。实验结果表明,假二级速率方程和Langmuir模型能更好地模拟相关实验数据,ATP-g-CTS对2,3,3'-TCB主要是化学吸附,是一个吸热的过程,ATP-g-CTS对多氯联苯是一种较好的吸附剂。     

凹凸棒土有机表面改性的工艺研究

采用硅烷偶联剂LM-N308对凹凸棒土进行有机表面改性.确定的改性工艺为:温度60℃以上,pH=3,时间3h,份数比m(LM-N308)/m(凹凸棒土)为15%.使用红外光谱和热分析对改性前后的凹凸棒土进行了表征,红外光谱结果表明硅烷偶联剂以化学反应的方式存在于凹凸棒土的表面;热分析结果表明凹凸棒土表面的硅烷偶联剂质量分数在4.8%左右.     

碱改性凹凸棒土对Cu2+吸附效果及其作用机理的研究

以改性凹凸棒土作为吸附材料,研究了搅拌时间、加热温度、氢氧化钠浓度对凹凸棒土进行改性,用改性凹凸棒土吸附Cu~(2+),通过正交实验确定了三个因素的影响顺序为:改性温度改性时间氢氧化钠浓度。当NaOH溶液浓度为5 mol/L,加热温度为90℃,搅拌时间为90 min时,改性凹凸棒土对Cu~(2+)的吸附效果最佳。通过XRD、FTIR表征了改性凹凸棒土的结构变化,研究发现改性凹凸棒土对Cu~(2+)吸附能力的增强可能是碱处理打开Si—O—Si(M)键,形成Si—O~—基团,提高了改性凹凸棒土的表面电负性;此外,凹凸棒土中部分高价阳离子(Al~(3+))可能被溶液中的Na~+所替代,也会导致电负性的增加。     

热塑性聚氨酯/凹凸棒土纳米复合材料力学行为研究

通过溶液共混法制备了热塑性聚氨酯（ TPU ）/凹凸棒土（ AT ）纳米复合材料,研究AT的加入对TPU基体滞后、拉伸应力软化行为和松弛效应的影响。研究结果显示：随着AT的加入,纳米复合材料的滞后圈增大,拉伸应力软化效应增强,应力松弛速率和程度降低。 TPU/AT体系分子链运动模型表明纳米复合材料力学行为的改变,可能是因为AT和TPU基体间形成了氢键,阻碍了分子链的运动。     

凹凸棒土及其改性物处理工业污水的研究进展

综述了国内外对凹凸棒土及其改性物处理工业污水的研究进展,从凹凸棒土的结构、特性、改性方法及在工业污水处理中的应用现状进行分析,发现改性后的凹凸棒土的吸附能力显著提高,并对凹凸棒土的发展趋势作了展望.     

凹凸棒土/硅橡胶复合材料性能的研究

以凹凸棒土为补强剂,采用机械共混法制备了具有优异力学性能的AT/MVQ复合材料.主要考察了凹凸棒土、改性剂、硫化剂双-2,5、羟基硅油对凹凸棒土/硅橡胶复合材料性能的影响.结果表明,凹凸棒土对硅橡胶具有较好的补强作用,凹凸棒土为80份时,AT/MVQ复合材料物理机械性能较佳;采用KH550 1.2份对凹凸棒土进行改性,AT/MVQ复合材料的拉伸强度提高了31.6%,撕裂强度提高了19.3%,100%定伸应力提高了131%,硫化剂双-2,5为2.0份、羟基硅油为5.6份时,AT/MVQ复合材料的拉伸强度最大可达8.38MPa.     

凹凸棒土的表面改性及其在不饱和聚酯树脂中的应用

采用硅烷偶联剂KH-151对纳米凹凸棒土进行了表面改性,并将其应用于不饱和聚酯树脂中。在改性温度为80℃的条件下,经偶联剂表面处理的凹凸棒土与不饱和聚酯树脂显示了良好的相容性,由此填料与树脂的界面结合强度增大。与纯树脂固化体相比,质量分数5%该填料填充的树脂样品其弯曲强度、断裂最大位移及破坏能量分别提高20%,55%及100%。     

银／凹凸棒土纳米复合材料的制备与表征

通过一种新颖而简单的方法,成功地制备了银／凹凸棒土纳米复合材料．巯基功能团对纳米凹凸棒土的表面修饰是重要步骤．TEM和AFM观察表明,银纳米粒子在凹土棒晶上呈线形沉积,类似于纳米线的形态。这在抗静电性及催化反应方面的应用具有很大价值．     

改性磁性壳聚糖去除水中双氯芬酸

为改善壳聚糖的吸附能力,探究壳聚糖吸附水中双氯芬酸的作用机理,采用原位共沉淀法制备磁性壳聚糖小球,并利用乙二胺对其进行改性.分别研究戊二醛、环氧氯丙烷和乙二胺等交联剂的投加量不同时,改性磁性壳聚糖对水中双氯芬酸吸附能力的差异.当戊二醛、环氧氯丙烷和乙二胺的投加量分别为4,12和6 mL时,制备的吸附剂(EMMCS-G)...     

使用膨胀石墨／ZnO复合材料去除水中甲基橙

分别加热醋酸锌和水洗后的可膨胀石墨、干燥后的可膨胀石墨和膨胀石墨（EG）的混合物,制备了3种不同的膨胀石墨／ZnO复合材料,分别记为EG／ZnO一1,EG／ZnO一2和EG／ZnO-3。使用X射线衍射分析（XRD）、扫描电子显微镜（SEM）和Branauer-Emmett—Teller（BET）比表面积等技术对样品结构进行表征。在紫外线（UV）照射下,研究了EG／ZnO对水中亚甲基橙的去除效率。结果表明,EG／ZnO同时具有膨胀石墨的吸附功能和ZnO的降解功能。在3种EG／ZnO中,EG／Zn0-3对水中甲基橙的去除效率最高。使用EG／ZnO-3,甲基橙去除率受EG／ZnO一3热处理温度和ZnO含量的影响。在优化工艺条件下,经过3．5huV照射,水中甲基橙可被完全去除。     

Lead removal from aqueous solution by employing natural brucite

The effect and mechanism of the removal of Pb^2 from an aqueous solution by using brucite as the adsorbent were studied. It was revealed that the increase in pH of brucite suspension, as a result of the release of magnesium hydroxide into the suspension, leads to a sharp rise of the adsorption amount of Pb^2 on brucite. The synergism of buffering and adsorption capacities of brucite is responsible for the removal of Pb^2 from the aqueous solution. The coexistence of Cu^2 with Pb^2 causes a decrease of their adsorption on brucite due to a competition for surface sites and brucite exhibits a higher adsorption capacity for Pb^2 than for Cu^2 . The percentage adsorption of Pb^2 on brucite could reach 96.38%, 97.20% and 94.09% respectively with the initial pH of the suspension pHi= 1,76 (initial Pb^2 concentration [Pb^2 ]i = 20μmol/L), 1.82 ([Pb^2 ]i=100μmol/L ) and 1.84 ([Pb^2 ]i = 500 μmol/L). It was concluded that brucite is a very efficient mineral adsorbent for Pb^2 removal from polluted acidic water.     

Removal of organic matter from H_2TaF_7 solution by adsorption

1　INTRODUCTIONIn the process of tantalum powder production,the organic matter in H2TaF7 solution can enter in to K2TaF7 crystal by adsorbing or enwrapping inthe crystallizing step[1, 2], thus rendering conse quently a higher carbon content of the tantalumpowder as a result. Impurity elements in the tanta lum powder, such as carbon, can influence thequality of the tantalum powder enormously, espe cially to the capacitor grade tantalum powder, re ducing the break…     

Removal of Cr（Ⅲ） and Cr（Ⅵ） from aqueous solution by adsorption on sugarcane pulp residue

Sugarcane pulp residue (SPR), a waste from sugar-refinery, which possesses a large surface area, can be used for removing chromium (Cr(III) and Cr(VI)) from wastewater. In this work, the kinetics, isotherms of Cr(III) and Cr(VI) adsorption and their removal by SPR were investigated. The results show that the removal percentages of Cr(VI) and Cr(III) increase with increasing SPR dosage and temperature and decrease with increasing SPR particle size and the initial concentration of chromium ions. However, the influence of pH value on the Cr(VI) removal differs from that of the Cr(III) removal. The Cr(VI) removal percentage decreases with increasing pH values, while the Cr(III) removal percentage increases with increasing pH value. The adsorption kinetics of Cr(VI) and Cr(III) well fits with pseudo-second-order model. Langmuir adsorption isotherm can well describe the adsorption phenomena of chromium ions with the maximum adsorption capacity of 0.567 mg/g for Cr(VI) and 3.446 mg/g for Cr(III). Moreover, SPR reveals higher adsorption capacity for Cr(III) than that for Cr(VI), which implies that SPR has more potential application for Cr(III)-containing wastewater treatment than that for Cr(VI)-containing wastewater treatment. Foundation item: Projects(2006AA06Z374, 2007AA021304) supported by the National High-Tech Research and Development Program of China; Project(2008SK2007) supported by the Key Program of Science and Technology of Hunan Province, China     

粉煤灰去除水中活性紫KN-B

以稀盐酸对燃煤电厂粉煤灰进行活化,实验了粉煤灰和活化粉煤灰对水中染料活性紫KN B的吸附脱色效果．实验结果表明：粉煤灰经活化后对染料的吸附能力明显增强．活化粉煤灰对染料活性紫KN B具有明显的脱色效果．在足量投加量下,废水脱色率可达99%以上;最佳pH值范围为2～8,最佳反应时间为15?min．粉煤灰和活化粉煤灰对水中活性紫KN B的吸附符合Langmuir吸附等温方程．活化粉煤灰用于实际印染工业废水处理,脱色率和COD去除率同样较高     

粉煤灰去除水中活性紫KN—B

以稀盐酸对燃煤电厂粉煤灰进行活化，实验了粉煤灰和活化粉煤灰对水中染料活性紫KN—B的吸附脱色效果．实验结果表明：粉煤灰经活化后对染料的吸附能力明显增强．活化粉煤灰对染料活性紫KN—B具有明显的脱色效果．在足量投加量下，废水脱色率可达99％以上；最佳pH值范围为2～8，最佳反应时间为15min．粉煤灰和活化粉煤灰对水中活性紫KN—B的吸附符合Langmuir吸附等温方程．活化粉煤灰用于实际印染工业废水处理，脱色率和COD去除率同样较高．