改性纤维素高吸水树脂对Cu~(2+)、Pb~(2+)的吸附性能研究

以羧甲基纤维素钠(CMC)为共聚骨架,丙烯酰胺(AM)、2-丙烯酰胺基-2-甲基丙磺酸钠(AMPS)和2-丙烯酰胺基十四烷基磺酸钠(Na AMC14S)为接枝单体,过硫酸铵(APS)为引发剂,N,N-亚甲基双丙烯酰胺(MBA)为交联剂,采用水溶液聚合法合成了一种新型CMC-g-poly(AM-co-AMPS-co-Na AMC14S)高吸水树脂,并添加氢氧化钠(NaOH)与酰胺基发生水解反应,使得酰胺基(—CONH_2)变成羧酸根(—COO-)。通过单因素优选法筛选出树脂对Cu2+、Pb2+的最佳吸附条件。当pH为4、吸附时间为12 h、树脂质量分数为0. 01%时,CMC-g-poly高吸水树脂对Cu2+、Pb2+去除率可分别达到85. 89%、82. 09%,展示出极好的吸附性能。吸附动力学表明,该吸附过程受化学吸附控制。重金属离子可以有效地被CMC-g-poly树脂吸附。     

酰基硫脲树脂的合成及其对Cu~(2+)的吸附性能研究

通过对苯二甲酰基二异硫氰酸酯与二乙烯三胺的界面缩聚反应,制备了一种含有硫脲基团的螯合树脂。产品基于对苯二甲酰基二异硫氰酸酯收率为91.92%。用红外光谱仪、扫描电子显微镜对树脂的化学结构、表面形貌、分散情况及其分布进行了表征。采用静态吸附法研究了该树脂对铜离子的吸附性能,树脂对Cu2+吸附在15 h后基本达到平衡,适宜的p H值在4.5左右,吸附量可达1.12 mmol/g。通过分析树脂吸附动力学和吸附等温线,表明对苯二甲酰基硫脲树脂对Cu2+的吸附规则遵循Boyd液膜扩散方程和Langmuir等温吸附方程,整个吸附过程为吸热过程。     

酰基硫脲树脂的合成及其对Cu~(2+)的吸附性能研究

通过对苯二甲酰基二异硫氰酸酯与二乙烯三胺的界面缩聚反应,制备了一种含有硫脲基团的螯合树脂。产品基于对苯二甲酰基二异硫氰酸酯收率为91.92%。用红外光谱仪、扫描电子显微镜对树脂的化学结构、表面形貌、分散情况及其分布进行了表征。采用静态吸附法研究了该树脂对铜离子的吸附性能,树脂对Cu2+吸附在15 h后基本达到平衡,适宜的p H值在4.5左右,吸附量可达1.12 mmol/g。通过分析树脂吸附动力学和吸附等温线,表明对苯二甲酰基硫脲树脂对Cu2+的吸附规则遵循Boyd液膜扩散方程和Langmuir等温吸附方程,整个吸附过程为吸热过程。     

一种高吸水树脂对电镀废水中铜离子的吸附研究

以废弃聚乙烯(PE)塑料与具有亲水性基团的丙烯酸(AA)及其盐接枝共聚合成一种高吸水性树脂,并将所得高吸水树脂用于溶液中Cu2+的吸附。通过分光光度法研究了树脂去除水溶液中Cu2+的情况,考察了起始pH、树脂用量、金属离子起始浓度和吸附时间对金属离子去除率的影响。结果表明,该树脂对Cu2+具有较强的吸附性能。树脂初期吸附速率大,吸附达到平衡时的接触时间为30 min。当溶液pH为7.0,Cu2+初始浓度为25 mg/L,树脂用量在8 g/L时,树脂对Cu2+的去除率可达95.0%以上。     

多乙烯多胺胺化大孔GMA-DVB树脂的合成及其对金属离子的吸附

采用悬浮聚合法合成甲基丙烯酸缩水甘油醚(GMA)-二乙烯基苯(DVB)共聚物大孔树脂,然后通过树脂中的环氧基与多乙烯多胺的反应得到相应的胺化吸附树脂。弱碱全交换容量、孔体积和孔隙率测试结果表明：随着交联剂用量的增加,氨基含量、孔体积和孔隙率降低;致孔剂用量增大,孔隙率和孔体积增加。胺化吸附树脂对Cu²⁺、Co²⁺、Ni²⁺和Zn²⁺的吸附动力学结果表明：所有胺化吸附树脂对金属离子的吸附符合伪二级速率方程,对4种金属离子均具有明显的吸附作用,其中对铜离子的吸附效果最好。     

丙烯酸乙酯与丙烯酰胺接枝淀粉/β-环糊精树脂的制备

采用无皂乳液聚合法制备丙烯酸乙酯(EA)与丙烯酰胺(AM)接枝淀粉/β-环糊精(β-CD)树脂,通过傅里叶变换红外光谱、扫描电子显微镜分析了树脂的结构,用原子吸收光谱法研究了树脂的吸附性能。结果表明:当淀粉用量为2.00 g,淀粉,β-CD,EA,AM质量比为2.0∶1.0∶1.0∶0.5,引发剂用量为0.03 g,交联剂用量为0.03g,聚乙烯醇用量为0.04 g,十二烷基硫酸钠为0.02 g,在50℃时反应5 h,得到的树脂接枝率最大。树脂对金属离子吸附量与金属离子结构、外层电子排布有关,吸附Cu2+,Mn2+的最佳时间分别为120,150 min;随着金属离子质量浓度及溶液pH值的增大,吸附量亦增大,且树脂对Cu2+吸附量大于Mn2+。树脂对色素胭脂红的吸附量随胭脂红质量浓度的增大而增大。当Cu2+,Mn2+和胭脂红初始质量浓度分别为50.0,50.0,40.0 mg/L时,吸附量分别为15.531 0,10.285 0,12.138 0 mg/g。     

水稻秸秆/膨润土基高吸水树脂的制备及其对Cu2+的吸附

以丙烯酸、丙烯酰胺为单体,水稻秸秆为有机材料,膨润土为无机材料,过二硫酸钾为引发剂,N-羟甲基丙烯酰胺为交联剂,采用水溶液聚合法制备了水稻秸秆/膨润土基高吸水树脂,并对其结构进行了表征。研究了溶液pH值、溶液初始浓度、树脂用量、吸附时间和温度对吸附Cu^2+的影响。结果表明:树脂对Cu^2+的吸附符合Langmuir等温模型,伪二阶动力学模型更能描述树脂对Cu^2+的吸附行为;吸附主要为单分子层吸附,吸附速率取决于表面的空吸附位点;温度越高越有利于反应的进行,且吸附过程中存在化学反应。     

聚2-丙烯酰胺-2-甲基丙磺酸高吸水性树脂等温吸附重金属离子

用溶液聚合法合成了聚2-丙烯酰胺-2-甲基丙磺酸(PAMPS)高吸水性树脂。研究了PAMPS树脂等温时Pb(NO3)2,Cu(NO3)2,Zn(NO3)2中溶液浓度、吸附时间对吸附的影响。结果表明,对Pb2+的吸附质量分数随Pb(NO3)2溶液浓度、交联剂浓度和中和度增加而增大;对不同金属离子的吸附质量分数随溶液浓度增加而增加,其吸附质量分数顺序为Pb2+Cu2+>Zn2+,Langmiur等温吸附方程能较好地拟合实验数据。吸附Pb2+的PAMPS树脂在1 mol/L HCl溶液中的解吸附比随时间延长而增加,解吸附10 min后解吸附质量分数基本达定值。     

一种巯基胺型羧酸螯合树脂的制备及其吸附性能

以环硫氯丙烷和多乙烯多胺为原料,通过交联反应合成了巯基胺型树脂(PA树脂)。然后对PA树脂进行氯乙酸化反应,合成了巯基胺型羧酸螯合树脂(PAC树脂),并通过傅立叶变换红外光谱仪(FTIR)对其结构进行了表征。研究了PAC树脂对模拟含Cu2+电镀废水的吸附性能,探讨了树脂用量、吸附时间和pH对Cu2+吸附性能的影响。实验结果表明,在常温常压下,取25 mL浓度为10 mmol/L的废水溶液,PAC树脂吸附Cu2+的最佳用量为0.40 g/mmol Cu2+,最佳吸附时间为150 min,最佳pH为6~10,最大吸附量和最大吸附率分别达到2.53mmol/g和94.7%。PAC树脂对Cu2+的吸附过程符合Langmiur和Freundlich等温吸附方程。     

氨基丙二醇功能化硼螯合树脂的制备及其硼酸吸附性能

分别用3-氨基-1,2-丙二醇（3-APD）和2-氨基-1,3-丙二醇（2-APD）对多孔氯甲基聚苯乙烯树脂（CMPS）进行修饰,制备得到含邻、间位二羟基官能团的硼螯合树脂：PS-3-APD和PS-2-APD。用傅里叶红外光谱仪（FTIR）、元素分析仪（EA）、压汞仪（MIP）和激光粒度仪（LPS）对材料进行表征,确认功能单体成功接枝于氯球上。对两种树脂进行了静态提硼性能研究,分别考察了原料液pH、初始硼酸浓度、外来金属离子对硼酸吸附量的影响,当溶液pH为9.15～9.20时,两种树脂对硼酸吸附量最大;溶液中Na⁺、Mg²⁺、Ca²⁺的存在会一定程度削弱树脂对硼酸吸附性能。吸附动力学表明其吸附速率较快,且均满足准二级动力学模型。与Freundlich相比,吸附等温线更符合Langmuir模型,拟合得到的理论最大吸附量分别为0.730mmol/g和0.868mmol/g。本文对未来新型硼螯合树脂的开发及工业化应用提供参考和指导。     

氢气纯度分析方法准确性的探讨

ONACCURACYOFANALYSISOFOFHYDROGEN1前言我公司目前应用的氢气纯度分析方法有两种,一种是爆炸反应法,另一种是焦性没食子酸吸收法。几年来,人们对两种分析方法的准确性曾有过褒贬不一的评论。这里我们也谈谈自己粗浅的观点。2爆炸法测定氢气纯度一定量的氢气样品与适量的空气之均匀混合物因反应后生成液体水而引起气体体积减少,减少的体积等于参加反应气体体积之和。其中l／3为氧气,2／3为氢气。根据氢气取样量和反应前后混气体体积之差,以及氢气在反应中的体积比例关系,可计算出样品的氢气纯度。计算公式式中：A一混…     

COMPARISON OF METHODS OF ANALYSIS OF GYPSUM1

The different analytical methods proposed for the evaluation of gypsum have been subjected to an experimental test. A combination method, consisting of a fusion with KHCO₃ and determination of CaO by KMnO₄ titration, the SO₃ by Andrews method of titration of BaCrO₄ has been found to give very reliable results with the least consumption of time.     

SEDIMENTATION OF BINARY MIXTURES OF PARTICLES OF UNEQUAL DENSITIES AND OF DIFFERENT SIZES

A model is developed for the sedimentation from a suspension of two particle species of unequal densities and of different sizes. The composition and the thickness of various layers in the sediments are predicted using graphical and analytical methods. The model predictions were in excellent agreement with experimental results, when the particle size ratio was ≥ 108. When size ratio of the particles was 2.60 and 4.31 the agreement occurred in about 50 percent of the cases.     

HEASUREHENT OF INSTANTANEOUS RATES OF LOSS OF VOIATILE COMPOUNDS DURING DRYING OF DROPS

A novel technique serves to monitor instantaneous rates of loss of a volatile solute from a suspended drop during drying. A highly sensitive electron capture detector is used to monitor concentrations of SF6 released into a flowing gas stream from a suspended, drying drop. Simultaneously, the appearance and morphological development of the drop are monitored with a video camera. This provides the wherewithal of relating instantaneous rates of loss of the volatile solute to particular events during the development of particle morphology.

Initial experiments have been carried out with drops of aqueous solutions of glucose, sucrose, maltodextrin and coffee extract. The results clearly display the onset of the volatiles-retentive selective diffusion phenomenon. There is also substantial loss of the volatile component later in the drying process, when the drops undergo repeated ex ansion, bursting and cratering due to the formation of internaf bubbles. These experiments appear to be the first quantitative demonstration of major losses accompanying changes in drop morphology.     

ANALYSIS OF RECENT MEASUREMENTS OF THE VISCOSITY OF GLASSES

Viscosity of Simple Soda-Silicate 500° to 1400°C Comparison of the results given by English with those of Washburn, Shelton and Libman, indicates a discrepancy in the absolute values of log₁₀ viscosity amounting to 0.6, those of Washburn et al., being relatively too high. If correction for this is made, the isothermal curves of log₁₀ viscosity as a function of soda content are smooth up to 50% Na₂O, showing no inflection. The observations as a function of temperature T are all represented within accidental error by an equation of the type where all three constants vary regularly with the composition. Change of Viscosity of Glass (6SiO₂, 2Na₂O) due to Molecular Substitution of CaO, MgO and Al₂O₃ for Na₂O The effect is clearly brought out by plotting (from the results of English) the change of log₁₀η due to the substitution as a function of temperature. The curves each show a sharp bend at a temperature between 840° and 1050°C, which is designated the aggregation temperature T_a. If we divide these curves by the corresponding percentage substituted, we get curves for each oxide which are straight and parallel below the aggregation temperatures, the slopes (increase of change of log₁₀η per 100°C) being −0.056 (CaO), −0.055 (MgO), −0.018 (A1₂O₃) per per cent oxide substituted. For substitution of 1/2 molecule the slopes are −0.325 (CaO), −0.23 (MgO) and −0.18 (Al₂O₃) per 100°. At the aggregation temperature the change of log₁₀η per per cent is a minimum, 0.03 to 0.06 for CaO, 0.12 for MgO, 0.07 for Al₂O₃. Evidence of Aggregation in Glasses, from viscosity Measurements The sharp bends in the plots of change of log₁₀η due to substitution of an oxide for Na₂O, suggest the beginning of molecular aggregation at these temperatures. These aggregation temperatures are close to the devitrification temperatures, but the effect on the viscosity curves cannot be due to actual devitrification since it does not change with time. Taking the aggregation temperatures as equal to devitrification temperatures, additional isotherms are roughly sketched into the equilibrium triangle of the system Na₂O-CaO-SiO₂. Change of Viscosity of Glass (4SiO₂, 2Na₂O) due to of Substitution of B₂O₃ for SiO₂ The change of log₁₀η (from the results of English) is plotted as a function of temperature, and also the change of log₁₀η per per cent B₂O₃. The curves are more complex than for the substitution for Na₂O.     

环氧树脂羟基值测定方法的研究

利用乙酸酐、吡啶和浓硫酸混合的乙酰化试剂测定环氧树脂中羟基值含量的方法具有操作简便、滴定终点明显和分析结果误差小等优点。     

骑式摩托车油箱喷涂工艺的改进

面对日益激烈的市场竞争,摩托车油箱外观质量越来越成为影响销售的因素之一。文章介绍了改进工艺后的油箱涂装,该涂装体系提高了油箱外观的丰满度,降低了油箱涂装的生产成本。     

茶多酚提取方法进展

本文综述了国内外现有茶多酚提取方法的现状以及近期的研究进展，并对其优缺点进行了评价。这将有助于中低档茶的综合利用和茶多酚的进一步开发应用。     

几种针状焦性能对比

针状焦分石油系和煤系两大类,这主要取决于针状焦的原料来源。在同一系列中由于原料不同和工艺条件不同 ,针状焦的各自性能也不相同。针状焦是生产超高功率石墨电极和高功率石墨电极的主要原料 ,针状焦的性能对石墨电极的质量有至关重要的影响。所以对针状焦性能以及其对石墨电极质量影响的研究十分必要的。以下是常用的几种进口针状焦和国产针状焦的性能对比。１原料性能分析对比原料试样包括４种针状焦 ,其中两种为进口针状焦：三菱针状焦和新日化针状焦;另两种为国产针状焦：鞍山针状焦和锦州针状焦。其中除锦州针状焦是石油系针状焦外…     

用两个形状指数表征粉煤灰颗粒形貌的研究

引用两个形状指数表征颗粒形状的概念,即先将颗粒形状近似为椭圆,再将椭圆图像分离:以圆为基准的颗粒宏观形状指数δ;以光滑椭圆为基准的颗粒轮廓凹凸度,即微观形状指数ζ。分析和发展了近似椭圆模型。并运用图像分析仪对粉煤灰、水泥样品进行实验。结果表明,粉煤灰颗粒的两个形状指数δ和ζ都大于水泥颗粒。证明粉煤灰颗粒的球形度、表面光滑度优于水泥,而且,随着粒径增大,δ和ζ呈下降趋势,表明磨制颗粒越粗。(?)粒形状越不规则。文中还运用近似椭圆模型再现了颗粒的模拟图像。