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1.
溶剂气浮法去除水中的刚果红的研究   总被引:3,自引:0,他引:3  
以十六烷基三甲基溴化铵为表面活性剂, 与阴离子型染料刚果红形成缔合物, 对该缔合物的溶剂气浮过程进行研究. 研究多种参数对溶剂气浮过程的影响, 如气浮速率、共存溶质的量、pH等参数对溶剂气浮去除率的影响. 研究表明表面活性剂与染料的物质的量之比为2∶1, 约24 min水中刚果红的去除率可达97%;NaCl会大大降低溶剂气浮的去除率;溶剂气浮的速率随着气流速率的增加而增加, 但高速率反而降低溶剂的去除率;共存溶质乙醇存在会使去溶剂去除率降低, 有机溶剂的量对溶剂气浮影响较小;pH中性去除率最佳;考察了不同温度下溶剂气浮的热力学及动力学, 研究表明, 溶剂气浮过程遵从一级动力学, 计算了该过程中的气浮表观活化能为7.48 kJ/mol.  相似文献   

2.
以双硫腙为配体,溴化十六烷基三甲基铵(CTAB)为表面活性剂。对Zn离子在无机相中形成的Zn-双硫腙-CTAB体系的溶剂气浮进行了研究。研究表明表面活性剂与Zn离子的物质的量之比为5:1,约1h水中的锌离子去除率可达98%。0.5mol/L NaCl大大提高体系的溶剂气浮的去除率,溶剂气浮的速率随着气流速率的增加而增加,共存溶质乙醇存在会使去除率降低,有机溶剂的量对溶剂气浮影响较小,溶剂气浮过程遵从假一级动力学。考察了不同温度下溶剂气浮的回收速率,计算了该过程中的气浮表观活化能为9.037kJ/mol。  相似文献   

3.
溶剂气浮法去除水中腐殖酸的动力学和热力学初步研究   总被引:5,自引:1,他引:4  
研究了溶剂气浮法去除水中的腐殖酸,该技术可以作为生物处理后的填埋渗出液的后处理方法。腐殖酸通过与表面活性剂十六烷基三甲基溴化铵生成离子缔合物气浮进入有机溶剂异戊醇而从水中去除。大于计量比的表面活性剂的量在10 m in之内可达92%的去除率。气浮速率在一定程序上随着气流速率的增加而增加,基本上与有机溶剂的体积无关。同时,还考察了电解质、乙醇及溶液的pH值对水中腐殖酸的溶剂气浮过程的影响。研究表明,该溶剂气浮过程遵从一级动力学。气浮过程的表观活化能作为一个特征参数被提出来,其值为2.87 kJ/mol。  相似文献   

4.
D301R树脂对水溶液中硝基苯的吸附性质   总被引:1,自引:0,他引:1  
研究了D301R弱碱性阴离子交换树脂对水中硝基苯的吸附作用,测定了不同温度下吸附的动力学曲线和吸附等温线,提出了吸附动力学模型,计算了平衡吸附量、吸附活化能和吸附焓等。 实验结果表明,吸附动力学符合表面过程控制的准二级反应模型,其速率常数k2在300 K时为3.74×10-2 g/(mg·min),并随温度的升高而升高;平衡吸附量在300 K时为5.02 mg/g,且随温度的升高而降低;吸附活化能为39.02 kJ/mol;吸附等温线符合Langmuir吸附模型,吸附焓为-22.47 kJ/mol,吸附作用力主要是氢键。  相似文献   

5.
以氯化1-丁基-3-甲基咪唑鎓([Bmim]Cl)和二元羧酸为原料,由不同摩尔比混合制备了一类新型低共熔溶剂,采用红外光谱对[Bmim]Cl和二元羧酸之间的作用进行了分析。分别测定了其粘度、电导率、密度、折射率等物理性质,并研究了温度、二元羧酸结构和摩尔比对这些物理性质的影响。结果表明,新型低共熔溶剂的粘度随温度的升高而降低,电导率随温度的升高而增加。温度对两者的影响可以采用VTF方程进行精确地拟合。新型低共熔溶剂的密度随温度的升高而呈线性下降。对新型低共熔溶剂的过量摩尔体积进行计算的结果表明,过量摩尔体积均为正值,二元羧酸对过量摩尔体积的贡献远大于[BMIM]Cl,而结构特性的贡献多于物理作用。折射率和密度随二元羧酸碳数的变化趋势基本相似。  相似文献   

6.
聚N,N-二乙基丙烯酰胺溶液粘度的温度依赖性   总被引:2,自引:0,他引:2  
通过自由基聚合,合成了线型聚N,N-二乙基丙烯酰胺(PDEA),用乌氏粘度计测定并考察了该聚合物在四氢呋喃(THF)、H2O以及THF-H2O混合溶剂中粘度的温度依赖性.实验结果表明,PDEA 在上述三种溶剂中粘度的温度依赖性不同,PDEA-THF体系的相对粘度随温度升高而增大;PDEA-H2O体系以及PDEA-THF-H2O体系的相对粘度随温度升高而减小,且THF体积分数φTHF < 0.7时具有透明-白浊转变现象;对PDEA-THF-H2O体系,φTHF增加,透明-白浊转变温度升高,而当φTHF=0.7时,则观察不到透明-白浊转变现象.  相似文献   

7.
利用红外光谱研究不同温度下CaCl2/甲醇溶液体系的溶剂化作用,结果表明在溶液中CaCl2以离子形式与甲醇发生溶剂化作用,且溶剂化数随温度升高而降低.通过密度泛函理论(DFT)在B3LYP/6-31G**水平下对CaCl2/甲醇溶液中可能存在的配位构型进行结构优化及热力学性质的计算,说明了在CaCl2/甲醇溶液中各种配位构型存在的可能性,得出温度升高热力学数据的变化规律,解释了溶剂化数随温度升高而降低的趋势.进一步对各种可能配位构型的红外吸收频率进行计算并与实验结果进行比较,推断在CaCl2/甲醇溶液中主要存在的配位构型为[CaCl(CH3OH)n]+和[Cl(CH3OH)n]-.  相似文献   

8.
常压升温下油煤浆表观黏度变化的研究   总被引:4,自引:0,他引:4  
为探讨煤直接液化工艺中油煤浆表观黏度随温度升高的变化规律,利用高温黏度计测定了煤浆体系的黏度,考察了溶剂、煤浆浓度、煤中含水量和不同显微组分等因素以及剪切速率、配浆温度、溶胀作用等对煤浆黏度 温度特性的影响。研究结果表明,低温下影响煤浆黏度变化的主要因素是溶剂本身的性质,煤浆的表观黏度随温度升高而降低;随温度继续升高在较宽温度范围内黏度变化不大,这是由溶剂性质以及煤在溶剂中的溶胀行为共同作用的结果;当温度达到约220℃后继续升高温度溶胀作用逐渐占优势,从而导致煤浆体系的表观黏度逐渐增大。  相似文献   

9.
合成了两种邻-氨基酚修饰超高交联吸附树脂(MOAR-1、MOAR-2),并用该树脂对水溶液中2-氨基吡啶的静态吸附热力学和动力学特征进行研究。热力学研究结果表明,Freundlich吸附等温方程能够对静态吸附等温线进行很好地拟合。吸附焓变ΔH<0,其绝对值小于60kJ/mol,表明以物理吸附为主以及该吸附剂容易脱附的特征;ΔG<0,说明吸附是自发行为;ΔS<0,表明吸附质分子在树脂表面上的运动受到了限制。两种树脂对2-氨基吡啶的吸附量随着温度的升高而降低,适当降低温度有利于吸附。动力学研究的结果表明:吸附符合一级动力学方程,吸附速率随温度升高而增大。表观活化能Ea<4.0kJ/mol,说明吸附较容易进行。  相似文献   

10.
D301R树脂对Keggin型铁取代杂多阴离子的吸附性能研究   总被引:5,自引:0,他引:5  
详细研究了D301R弱碱性阴离子交换树脂对Keggin型铁取代杂多阴离子PW11O39Fe(III)(H2O)4- (PW11Fe)的吸附作用, 考察了不同pH和温度对吸附量和吸附速率的影响, 测定了不同温度下吸附的动力学曲线和吸附等温线, 提出吸附动力学模型和计算了吸附的热力学函数, 结果表明, 在pH 2~8的范围内, PW11Fe的吸附量随溶液pH值的升高而增加, 随溶液温度的升高而降低; 吸附动力学符合表面过程控制的准二级反应模型, 其速率常数k2在298 K时为 9.33×10-4 g&#8226;mg-1&#8226;min-1, 并随温度的升高而减小. 吸附等温线符合Freundlich吸附模型, 吸附热约为40 kJ&#8226;mol-1, 因此, 吸附为物理吸附.  相似文献   

11.
Solvent sublation has been performed on very dilute solutions of one cationic surfactant, hexadecylpyridinium chloride (HPC), and one anionic surfactant, dodecylbenzenesulfonic acid (LBS). Some thermodynamic values were obtained, e.g. molecular areas, A0, which are 50.0 and 47.7 A2/molecule, respectively, for HPC and LBS, and free adsorption energies, delta G(o)ads, which are -33.17 and -43.58 kJ mol(-1), respectively, for HPC and LBS. The kinetics were determined for a range of temperatures and gas flow-rates. Although the processes of solvent sublation of the two surfactants obey first-order kinetics, the respective adsorption mechanisms of HPC and LBS in the solvent sublation process were different. The pH and the presence of KCl and ethanol had no effect on the solvent sublation of LBS. The apparent active energy was calculated as 8.11 kJ mol(-1).  相似文献   

12.
溶剂浮选分离富集麻黄草中有效成分   总被引:18,自引:1,他引:17  
董慧茹  王士辉 《分析化学》2004,32(4):503-506
采用溶剂浮选法分离富集麻黄草中的有效成分。考察了浮选溶剂、氮气流速、试液pH、浮选时间及电解质NaCl等因素对浮选效率的影响,优选出最佳浮选条件;对最佳条件下的浮选结果进行了评价,并与溶剂萃取法进行了对照;对麻黄草有效成分的浮选过程进行了初步探讨,浮选过程符合一级动力学方程。  相似文献   

13.
The kinetics and thermodynamics of surfactants in solvent sublation   总被引:1,自引:0,他引:1  
Solvent sublation has been performed on very dilute solutions of one cationic surfactant, hexadecylpyridinium chloride (HPC), and one anionic surfactant, dodecylbenzenesulfonic acid (LBS). Some thermodynamic values were obtained, e.g. molecular areas, A0, which are 50.0 and 47.7 Å2/molecule, respectively, for HPC and LBS, and free adsorption energies, ΔG°ads, which are –33.17 and –43.58 kJ mol–1, respectively, for HPC and LBS. The kinetics were determined for a range of temperatures and gas flow-rates. Although the processes of solvent sublation of the two surfactants obey first-order kinetics, the respective adsorption mechanisms of HPC and LBS in the solvent sublation process were different. The pH and the presence of KCl and ethanol had no effect on the solvent sublation of LBS. The apparent active energy was calculated as 8.11 kJ mol–1.  相似文献   

14.
The application of solvent sublation in the removal of humic acids was investigated in the present study. The humic acids (HA) were removed from an aqueous solution by solvent sublation of humic acid-hexadecylpyridium chloride (HPC) complex (sublate) into isopentanol. Several parameters were examined towards the optimization of humic acid removal; the dosage of a surfactant was found to be the major one, controlling the overall efficiency of the progress. The removal rate was somewhat enhanced by higher airflow rate and almost independent of the volume of the organic solvent floating on the top of the aqueous column. The effects of electrolytes (e.g., NaCl), nonhydrophobic organics (e.g., ethanol), and pH of the solution upon the process were studied. Under the optimized condition, the treatment performance was found to be very efficient, reaching almost 100%, indicating that solvent sublation can serve as a possible alternative technology for the removal of humic acids. The solvent sublation process follows first-order kinetics. A characteristic parameter, apparent activation energy of attachment of the sublate to bubbles, was estimated at a value of 9.48 kJ/mol. Furthermore, the simulation of a mathematical model with the experiments on the solvent sublation of humic acid-HPC was described here.  相似文献   

15.
采用溶剂浮选法分离富集葛根中的大豆甙元。考察了浮选溶剂、氮气流速、试液pH、浮选时间及电解质(KC1)等因素对浮选效率的影响,优选出最佳浮选条件;对最佳条件下的浮选效果进行了评价,并与溶剂萃取法进行了对照,前者明显优于后者。  相似文献   

16.
溶剂浮选法分离富集茶叶中茶多酚的研究   总被引:5,自引:0,他引:5  
采用溶剂浮选法分离富集了茶叶中的茶多酚。考察了浮选溶剂、氮气流速、试液pH及浮选时间等因素对浮选效率的影响,优选出最佳浮选条件;对最佳条件下的浮选效果进行了评价,并与溶剂萃取法进行了比对,前者明显优于后者。  相似文献   

17.
Separation of metal ion complex, [(C(12)H(8)N(2))(3)Fe(2+)], with surfactant sodium dodecylphrate (DLS) complex from aqueous phase was carried out by solvent sublation, which obeys first-order kinetics. On the base of the complete transport mechanisms, the Langmuir adsorption, and the ion complex equilibrium in the aqueous phase, a mathematical model for the [(C(12)H(8)N(2))(3)Fe(2+)]-surfactant ion complex is obtained with the aid of the Mathematic 4.0 program, 4th Runge-Kutta method, and the Matlab programs. The effects of many parameters, such as K(a), K(l), K(ow), d(i), V(o), V(w), and Q(a), on solvent sublation are investigated. Furthermore, the simulation showed that the model is substantiated for experiments on the solvent sublation of the complex.  相似文献   

18.
Dinitrophenol was removed from aqueous solution by various adsorptive bubble separation techniques. Foam fractionation of dinitrophenol with hexadecyltrimethylammonium bromide(HTA) was most effective with over 99% removal in 15 min. The addition of a surfactant in greater than stoichiometric amounts was required for effective separation. Solvent sublation of the dinitrophenol-HTA complex was also effective. The separation efficiency of solvent sublation of dinitrophenol-HTA was similar to that of foam fractionation. The separation by solvent sublation of dinitrophenol without adding any surfactant was very poor. Adsorbing colloid flotation with Fe(OH)3 was not effective in removing dinitrophenol from aqueous solution.  相似文献   

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