碳纳米管对结晶紫的吸附研究

研究了碳纳米管对溶液中结晶紫的吸附性能,考察了溶液浓度、溶液p H、吸附时间和吸附温度等因素对吸附行为的影响,初步探讨了碳纳米管对结晶紫的吸附机理。结果表明,碳纳米管对结晶紫的吸附量随着溶液初始浓度的增大而升高;酸性条件有利于吸附的进行,最佳p H等于5;对结晶紫的吸附在3h达到平衡,吸附速率常数为779.76h-1;温度的变化对结晶紫的吸附量影响不大。通过Langmuir方程和Freundlich方程对吸附进行拟合,平衡吸附量Qe与平衡质量浓度Ce之间的关系符合Freundlich等温吸附方程所描述的规律,说明吸附过程以物理吸附为主。     

关于Gibbs吸附等温式的推导

Gibbs吸附等温式■是表面化学的一个重要公式,主要用于溶液的表面吸附,也用于两个溶剂互不相溶的溶液之间。但它是用热力学原理推出的,故原则上能用于任何两个平衡相之间,是具有普遍意义的吸附公式。通过Γ_i和Γ_i~1可以定量地说明什么是正吸附和负吸附。Gibbs公式表示组分i的吸附量与表面张力σ随体相中i的浓度的变化     

CuY型分子筛制备及吸附脱硫影响因素研究

通过液相离子交换法制备CuY型分子筛,并利用正交实验得到了制备过程中交换时间、交换温度、铜离子浓度的最佳条件。系统研究了CuY分子筛的焙烧温度、吸附时间、吸附温度对其吸附脱除模拟油中二苯并噻吩(DBT)的影响。采用XRD、ICP及BET比表面积分别对不同CuY分子筛的骨架结构及阳离子负载量进行了研究。结果表明,二次交换后,分子筛已达到交换平衡,最佳焙烧温度为450℃,温度过高会破坏分子筛的骨架结构;分子筛上的吸附水对其吸附脱除二苯并噻吩的能力有较大的影响。     

6-氨基青霉烷酸在弱碱性阴离子树脂IRA67上的吸附研究

用静态法研究了6-氨基青霉烷酸在弱碱性阴离子交换树脂IRA67上的吸附行为．在溶液pH为8．0，6-APA起始浓度介子3.00mg／m1-20．00mg／ml条件下，测定了25℃时IRA67树脂的静态交换动力学曲线、吸附等温线，并求得了IRA67树脂的平衡速率常数及吸附等温线方程．分别用Langmuir型和Frendlich型方程对IRA67树脂吸附等温线进行线性回归拟合，结果表明，6-APA在IRA67树脂上的吸附更符合Langmuir型吸附．     

双变性淀粉吸附剂的合成及吸附性能研究

以环氧氯丙烷、交联化淀粉和丙烯腈为原料,水为溶剂,硝酸铈铵为引发剂,通过接枝反应合成了双变性淀粉吸附剂。其最佳制备工艺条件是交联化淀粉2g,硝酸铈铵浓度0.004mol/L,丙烯腈浓度0.3774mol/L,接枝温度35℃,接枝时间240min,料液比1:10(W/V)。对制得的双变性淀粉进行金属离子吸附性能评价,发现Cr6 吸附时使溶液处于中性或微酸性环境下,Cu2 吸附时使溶液处于弱碱性环境下,Cu2 的吸附率达到86.3%,Cr6 吸附率达78.2%,Cu2 吸附效果大于Cr6 。     

硅胶表面上聚酰胺-胺的合成及其对fe(ⅲ)的吸附

用硅烷偶联剂对硅胶表面进行氨基功能化,利用氨基与丙烯酸甲酯发生的Michael加成反应和乙二胺与酯进行的交换反应在硅胶表面合成了聚酰胺-胺树状大分子(PAMAM-SG). 利用红外光谱对PAMAM-SG的结构进行了表征. 研究了溶液pH值、浓度和温度对PAMAM-SG吸附 Fe(Ⅲ)的影响. 结果表明,溶液的最佳pH值为3.0～6.0;吸附速率随时间的增加而逐渐降低,随温度的升高显著升高;在40 ℃时具有较好的吸附性能,吸附3 h后均达到了完全吸附,吸附量达55.85 mg/g. 吸附容量随浓度的增大而增加直至平衡.各代PAMAM-SG的吸附量依次为2.0G＞1.0G＞1.5G＞0.5G＞0G.     

煤在含有吡啶的二元溶液中吸附和溶胀行为的研究

本实验采用WK11模型化合物及ND褐煤和IL烟煤，在含有吡啶的水、环己烷、甲苯双溶液系统中研究其吸附和溶胀行为。研究结果显示，在稀溶液条件下吡啶吸附量和溶胀率都很低，而且即使在很长的反应时间内溶液中的吡啶也不能被全部吸附。这表明虽然由于热力学有利的熵变，吡啶可以断开煤中所有的氢键交联结构而形成新的氢键，但溶剂环境的影响和孔径等因素的扩散限制，也显著影响煤的吡啶吸附量和溶胀行为。在低吡啶浓度时，煤的溶胀率与吸附量无线性关系。在高吡啶浓度时，溶胀率随吸附量的增大而增加。但吡啶浓度超过一定值时，由于吡啶的强抽提作用，一定反应时间后煤和溶剂界面消失。     

天然沸石粉阳离子吸附性能分析方法的探讨

通过比较不同浓度的NH4Ac溶液对天然沸石粉所吸附的碱金属和碱土金属离子多次连续提取的效果,将由交换性K^ 、Na^ 、Ca^2 和Mg^2 加和所获得的阳离子交换量与由常规土壤阳离子交换量测定法获得的阳离子交换量进行比较,发现常规的土壤分析方法不适于测定天然沸石粉所吸附的交换性K^ 、Na^ 、Ca^2 和Mg^2 及阳离子交换量。建议用K^ 、Na^ 、Ca^2 和Mg^2 5次提取总量分别作为天然沸石粉所吸附的交换性K^ 、Na^ 、Ca^2 和Mg^2 的估算值,并把其提取量加和作为沸石粉阳离子交换量的估算值．     

复合提锂吸附剂的成型工艺及性能研究

针对离子筛成型时成型工艺参数不明确的问题，以Li_1.33Mn_1.67O₄为研究对象，使用反溶剂成型法合成复合吸附剂P-LMO，进行成型工艺及性能的研究。通过对进料管径、进料速度、反溶剂搅拌速度、聚氯乙烯(PVC)的聚合度、PVC和溶剂的配比等因素考察离子筛成型的规律，确定最佳合成条件为进料管径3.2mm、进料速度1～3mL/min、反溶剂搅拌速度50～200rpm、PVC的聚合度1300、PVC和溶剂配比为75mg/mL时，获得粒径为3mm的球形复合吸附剂。通过对比磨损率和硬度确定PVC理论添加量为20%。吸附实验结果表明，在pH=10、锂离子初始浓度为150mg/L的溶液中吸附40h，吸附达到平衡，吸附容量为7.5mg/g。     

从模拟放射废液中去除Ce（Ⅳ）的吸附剂筛选和性能研究

研究了多种MOF材料对溶液中铈离子的吸附性能，经过对比得出，铜基MOF材料Cu-BTC对Ce（Ⅳ）的吸附效果最佳。采用SEM,BET,XRD,FT-IR等方法对其结构和形貌进行表征，并考察平衡时间、温度、初始浓度、pH、离子强度等参数对吸附行为的影响；对吸附前后的Cu-BTC进行XPS分析，考察其对Ce（Ⅳ）的吸附机制；另以实际放射性废水作为研究对象，探究Cu-BTC对真实放射性废液中α核素的吸附性能。结果表明：Cu-BTC对Ce（Ⅳ）离子的吸附在2 h内达到吸附平衡，吸附剂投加量一定时，平衡吸附量随溶液中铈离子初始浓度的增大而增大，平衡吸附率反之；溶液pH的增大与离子强度的减小可促进Cu-BTC对Ce（Ⅳ）的吸附；吸附等温线的研究表明Cu-BTC的吸附行为符合Langmuir等温吸附模型，以化学吸附为主，吸附过程为自发的吸热反应，低温有利反应的进行。此外，Cu-BTC对实际放射性废水中的α核素有较好的处理效果，平衡吸附比为52.51%。     

黄姜中薯蓣皂甙元的提取、纯化及其鉴定

以湖南浏阳的盾叶薯蓣为实验材料,从发酵时间、水解时间、抽提物的pH值、回流时间对盾叶薯蓣皂甙元提取率的影响进行了研究。结果表明,发酵时间24h,水解4h,回流时间为5h,抽提物pH值近中性时可获得最佳提取率。用硅胶层析加重结晶的方法对薯蓣皂甙元粗品进行了提纯,并对纯品的结构进行了初步鉴定。     

不同工艺的荔枝核提取物抗氧化活性的比较

分别采用回流提取、热浸提取、微波辅助提取法分离荔枝核活性成分,测定了不同工艺制备的荔枝核提取物抑制油脂氧化以及清除羟基自由基和超氧阴离子自由基的抗氧化活性.结果表明,荔枝核提取物具有较强的抗氧化活性,能够有效地抑制油脂氧化;不同工艺的提取物对油脂抗氧化作用的排序为微波提取物热浸提取物回流提取物.与此同时,荔枝核提取物能够有效地清除羟基自由基,其中微波提取物的半清除率质量浓度(EC50)约为0.76 g/L,热浸提取物的EC50约为0.94 g/L,回流提取物的EC50约为2.0 g/L.此外,荔枝核提取物对超氧阴离子自由基也有一定的清除效果.     

Microwave Accelerated Extraction and Capillary Electrophoresis Analysis of Berberine from the Cortices of Phellodendron Wilsonii and Phellodendron Amurense

Berberine is one of the most important bioactive compounds used in Chinese herbal drugs to evaluate the quality of the Phellodendron cortex. The cortices of Phellodendron wilsonii and Phellodendron amurense, extracted by using a microwave‐assisted process under a domestic microwave oven in methanol solvent and analyzed by capillary electrophoresis with the buffer solution of 82% 0.1 M aqueous sodium acetate and 18% MeOH (v/v), were demonstrated to be higher in extracting berberine contents and shorter in the process time than those extracted by using a reflux extraction in methanol solvent (for sample B, 2.27 ± 0.08% in 3 min vs. 1.92 ± 0.14% in 5 hrs, respectively). Therefore, the microwave‐assisted process for extraction of berberine is more efficient, rapid and convenient than the reflux extraction and can be used for the extraction of bioactive substances from the crude Chinese drugs.     

微波辅助-旋转回流提取叶下珠中的没食子酸

A new kind of microwave-assisted circumrotation reflux extraction device was constructed and used to study the extraction technology of gallic acid from phyllanthus urmaria L.The extraction principle of the device was same as that of microwave-assisted solvent extraction but using circumrotation techniques as auxiliary stirrer to accelerate the process.Capillary electrophoresis was used to determinate gallic acid in phyllanthus urmaria L extracts in order to evaluate the extraction efficiency of the method.It was found that the most important factors influencing extraction gallic acid were solvent kind and microwave power.The optimum extraction conditions were as follows:water using as irradiate time 4 minute.Under the optimum extraction conditions,five experiments were carried out and the average extraction rate of gallic acid in phyllanthus urmaria L was 4.32 mg/g,relative standard deviations (R.S.D.) was 2.2%.Compared with other extraction methods e.g.reflux extraction and microwave-assisted extraction,better extraction efficiency was observed for the microwave-assisted circumrotation reflux extraction.     

Optimization of the Ultrasonic-Assisted Extraction Technology of Steroidal Saponins from Polygonatum kingianum Collett & Hemsl and Evaluating Its Quality Planted in Different Areas

Polygonatum kingianum Collett & Hemsl is one of the famous traditional Chinese herbs with satisfactory therapeutic effects on invigorating Qi, nourishing Yin and moistening lungs, in which steroidal saponins are one class of important active substances. The main purpose is to determine the optimal extraction technology of steroidal saponins and evaluate the quality of P. kingianum planted in five different areas. The optimal ultrasonic-assisted extraction (UAE) technology was established by using single-factor experiments and the response surface methodology (RSM), and the determination method of high-performance liquid chromatography (HPLC) for dioscin and diosgenin, two primary types of acid-hydrolyzed steroidal saponins, was constructed with good linear range and precision. The results showed that UAE was an efficient extraction method for steroidal saponins, and the extraction yield was significantly affected by the liquid-solid ratio. The optimal extraction technology was generated following a liquid-solid ratio of 10:1 (mL/g), an ethanol concentration of 85% (v/v), an extraction time of 75 min, an extraction temperature of 50 °C and three extractions, of which these parameters were in line with the predicted values calculated by RSM. Considering only dioscin and diosgenin, the quality of P. kingianum planted at five sample plots presented non-significant difference. However, the content of diosgenin in Pingbian Prefecture (PB) was higher than that of the other four areas with a value of 0.46 mg/g. Taken together, the optimal UAE technology for P. kingianum steroidal saponins was determined via RSM. The quality evaluation revealed that there was a non-significant difference among P. kingianum planted in different areas based on the contents of the sum of dioscin and diosgenin. This work has important reference value for the exploitation and utilization of P. kingianum.     

Extraction and Analysis of Six Effective Components in Glycyrrhiza uralensis Fisch by Deep Eutectic Solvents (DES) Combined with Quantitative Analysis of Multi-Components by Single Marker (QAMS) Method

Deep eutectic solvents (DESs) are green organic solvents that have broad prospects in the extraction of effective components of traditional Chinese medicine. This work employed the quantitative analysis of multi-components by a single marker (QAMS) method to quantitatively determine the six effective components of glycyrrhizic acid, liquiritin, isoliquiritin apioside, liquiritigenin, isoliquiritin, and glycyrrhetinic acid in Glycyrrhiza uralensis, which was used for comprehensive evaluation of the optimal extraction process by DESs. First, Choline Chloride: Lactic Acid (ChCl-LA, molar ratio 1:1) was selected as the most suitable DES by comparing the extraction yields of different DESs. Second, the extraction protocol was investigated by extraction time, extraction temperature, liquid-to-material ratio, molar ratio, and ultrasonic power. The Box–Behnken design (BBD) combined with response surface methodology (RSM) was used to investigate the optimal DES conditions. The result showed that the best DES system was 1.3-butanediol/choline chloride (ChCl) with the molar ratio of 4:1. The optimal extraction process of licorice was 20 mL/g, the water content was 30%, and the extraction time was 41 min. The comprehensive impact factor (z) was 0.92. At the same time, it was found that the microstructure of the residue extracted by the eutectic solvent was more severely damaged than the residue after the traditional solvent extraction through observation under an electron microscope. The DES has the characteristics of high efficiency and rapidity as an extraction solution.     

Development and optimisation of a novel three‐way extraction technique based on a combination of Soxhlet extraction,membrane assisted solvent extraction and a molecularly imprinted polymer using sludge polycyclic aromatic hydrocarbons as model compounds

A novel technique that integrates extraction and clean‐up into a single step format is reported as part of the search for new sample preparation techniques in the analysis of persistent organic pollutants from complex samples. This was achieved by combining the extraction efficiency of the Soxhlet extractor, the selectivity of a size exclusion membrane and the specificity of a molecularly imprinted polymer for the extraction of polycyclic aromatic hydrocarbons from wastewater sludge followed by quantitation using gas chromatography with time‐of‐flight mass spectrometry. The approach is described as the Soxhlet extraction membrane‐assisted solvent extraction molecularly imprinted polymer technique. This technique was optimised for various parameters such as extraction solvent, reflux time and membrane acceptor phase. The applicability of the developed technique was optimised using a wastewater sludge certified reference material and then tested on real wastewater sludge samples. The method detection limits ranged from 0.14 to 12.86 ng/g with relative standard deviation values for the extraction of the 16 US‐EPA priority polycyclic aromatic hydrocarbons from wastewater sludge samples ranging from 0.78 to 18%. The extraction process was therefore reproducible and showed remarkable selectivity. The developed technique is a promising prospect that can be applied in the analysis of organic pollutants from complex solid samples.     

神华煤直接液化残渣超临界溶剂萃取研究

利用甲苯、苯和乙醇三种溶剂在反应釜中对神华煤直接液化残渣进行了超临界溶剂萃取,考察了压力、温度、萃取时间、溶剂/残渣比等对萃取产物收率和重质液体萃取组成的影响。结果表明,以甲苯为溶剂进行萃取时,萃取时间对重质液体产率及HS和A收率的影响不大,而温度、压力以及溶剂/残渣质量比都会影响萃取产物的产率及组成。溶剂超临界萃取过程中,有其他组分向HS组分转化,提高了HS的收率。三种溶剂中,苯显示了和甲苯相似的萃取性能,而乙醇的萃取性能相比苯和甲苯则较差,但乙醇萃取得到的重质液体中轻质组分含量高于苯和甲苯。萃取过程中,残渣中的灰分和硫分主要富集至萃取残渣中。     

重楼中薯蓣皂甙元的反相高效液相色谱测定

采用高效液相色谱法测定了重楼中薯蓣皂甙元的质量分数。样品先经甲醇提取,再经酸水解,将重楼甾体皂甙转变成薯蓣皂甙元,以ＳｙｍｍｅｔｒｙＣ８柱为色谱柱,以Ｖ（乙腈）∶Ｖ（水）＝７５∶２５溶液为流动相,检测波长２０３ｎｍ,重复性较好,结果令人满意。     

微波辅助-旋转回流提取仪的组装及其在叶下珠有机酸提取中的应用

组装了一种新型的微波辅助旋转回流装置,该装置的基本原理与微波辅助溶剂萃取的原理相同,但采用了旋转的技术以加速提取.应用该装置以正交实验筛选优化叶下珠中有机酸的提取工艺,并利用毛细管电泳技术分离测定了提取液中有机酸的含量以评价提取效果.最佳提取工艺:乙醚为溶剂,微波功率800 W,提取时间4 min,溶剂用量300 mL.在该提取条件下,平行5次提取叶下珠中丁二酸、原儿茶酸、没食子酸、咖啡酸、阿魏酸的平均含量分别为42.2、103.5、436.2、123.8、67.4 μg/g,相对标准偏差为0.87% ～3.7%,加标回收率为94% ～104%.将该法与常规的微波辅助提取法及回流提取法进行比较,结果表明,微波辅助旋转回流提取法提取效率明显优于其它2种方法.