脱色希瓦氏菌S12对十溴联苯醚的利用及其降解特性研究

针对目前日益严重的多溴联苯醚污染问题,研究脱色希瓦氏菌S12在厌氧条件下对十溴联苯醚的利用及其降解特性.通过测定OD600值和电子显微镜观察分析S12菌的生长情况,并采用GC-MS分析十溴联苯醚(BDE-209)及其代谢产物的含量和组成.结果表明,在二甲基亚砜助溶条件下脱色希瓦氏菌S12能以BDE-209为厌氧呼吸的电...     

络合萃取法分离甲酸稀溶液的研究

以三辛胺TOA为络合萃取剂,正辛醇稀释改质剂,对甲酸稀溶液进行络合萃取研究.讨论了萃取剂在有机相中的浓度、萃取平衡温度和盐析效应对萃取过程的影响,并对萃取剂进行再生利用;实验结果表明在室温条件下,萃取剂采取37％TOA+ 63％正辛醇有较好的萃取效果,加入盐析剂后萃取率达到99％以上;并利用红外光谱法对萃取特征和机理进行进一步探讨.     

液相微萃取-GC-MS法测定水中的杀真菌剂类农药

用中空纤维膜液相微萃取一气相色谱质谱法测定水中的杀真菌剂类农药（乙烯菌核利、腐酶利）。通过试验选择甲苯为萃取剂,研究了萃取剂的选取及其用量、萃取温度、萃取时间、搅拌速度对萃取的影响。在最佳条件下富集倍数为：乙烯菌核利134倍、腐酶利209倍。方法的线性范围为0．50—1001μg·L-1,检出限为0．05和0．08μg·L-1,测定实际水样加标回收率分别为87．1％和86．3％、相对标准偏差≤9．43％,此方法简单、快速、成本低,可用于水中的杀真菌剂类农药的快速检测。     

微波法修复十溴联苯醚污染土壤的影响因素

采用微波辐照技术修复十溴联苯醚(BDE-209)污染土壤,以自制无氧微波试验系统为试验装置,考察微波功率、土壤量、土壤含水率、土壤初始pH和微波吸收剂在不同微波辐照时间下对BDE-209去除率的影响。结果表明,在所有影响因素下,BDE-209去除率都随微波辐照时间的增加而增大;微波功率过高,将对土壤表面形态产生不良影响;最优工艺参数为960 W、30 g土壤、20%含水率、pH 2.59、10%(质量分数)活性炭添加、辐照10 min,即可将BDE-209完全去除且不改变土壤表面形态特征。     

微波法修复十溴联苯醚污染土壤的影响因素

采用微波辐照技术修复十溴联苯醚(BDE-209)污染土壤,以自制无氧微波试验系统为试验装置,考察微波功率、土壤量、土壤含水率、土壤初始pH和微波吸收剂在不同微波辐照时间下对BDE-209去除率的影响。结果表明,在所有影响因素下,BDE-209去除率都随微波辐照时间的增加而增大;微波功率过高,将对土壤表面形态产生不良影响;最优工艺参数为960 W、30 g土壤、20%含水率、pH 2.59、10%(质量分数)活性炭添加、辐照10 min,即可将BDE-209完全去除且不改变土壤表面形态特征。     

光催化还原十溴联苯醚

以模拟太阳光为光源,首次研究了TiO2悬浮体系中十溴联苯醚（BDE-209）的光催化还原反应,讨论了TiO2投加量、BDE-209初始浓度、空穴清除剂对反应的影响。结果表明TiO2悬浮体系对BDE-209的光降解效果明显。当TiO2为1 g/L,甲醇作为空穴清除剂时,2.5 h后的降解效果最好,降解率达到78.6%,降解过程符合一级反应动力学方程,反应动力学常数为0.0103 min-1。利用光催化还原法制备了Ag/TiO2催化剂,采用TEM、EDS对催化剂进行表征,并进一步研究了Ag/TiO2光催化还原BDE-209,发现30 min内降解率即可到达96%。     

超临界CO2流体萃取大黄游离蒽醌的研究

研究了带夹带剂的超临界流体萃取大黄中的五种有效蒽醌类物质(大黄酚、大黄素、芦荟大黄素、大黄酸和大黄素甲醚)的工艺,考察了萃取条件(温度和压力)、CO2流量、萃取时间、夹带剂种类等对大黄游离蒽醌萃取率的影响.通过正交实验对萃取釜条件(萃取压力、温度和夹带剂用量)进行了优化;采用液相色谱对萃取产物进行了分析.结果表明,分离釜的温度和压力、CO2流量等对萃取效率影响较小;最佳工艺条件为静萃取时间为60 min、动萃取时间为30 min、以乙醇作夹带剂、乙醇用量300 mL·(100g大黄)-1、萃取温度45℃、萃取压力45 MPa.在此条件下大黄游离蒽醌的萃取量达1.15%.     

粗制硫酸铝萃取除铁工艺的研究

本文利用自制的萃取剂Ａ,对粗制硫酸铝溶液〔１〕中的萃取除铁效率进行了实验研究,并探讨了萃取剂的再生方法和适宜条件。实验结果表明：使用萃取剂Ａ,对粗制硫酸铝溶液萃取二次,可使２８００ｐｐｍ 的铁减少到３０ｐｐｍ 以下,达到无铁硫酸铝的要求,而铝几乎不损失。对使用过的萃取剂以２．７％ 的硫酸溶液反萃取二至三次后,再通过水洗,碱洗,水洗,即实现再生,可以循环使用。     

以硝基苯为萃取剂从水中回收苯胺工艺技术研究

介绍了采用硝基苯为萃取剂,从水中回收苯胺的工艺过程,进行了溶剂比、萃取级数、萃取温度对萃取效果的影响实验,确定了适宜的工艺条件.由于硝基苯为苯胺的生产原料,以其为萃取剂无需再生,可将萃取相直接加氢生产苯胺.通过三级逆流萃取,可使萃取后水中w（苯胺）由3.6％降至0.003 0％,苯胺回收率达到99.9％以上.     

夹带剂对超临界CO2萃取茄尼醇过程的强化

夹带剂强化技术可显著提高超临界CO2萃取茄尼醇的萃取效率. 本工作在分析讨论萃取机理及夹带剂强化作用的基础上,研究了影响强化效应的夹带剂种类、用量、输入方式3个主要因素及其对茄尼醇萃取率的影响规律,并讨论了夹带剂与茄尼醇从萃取混合物中二级选择性解析的问题. 在设计夹带剂强化萃取茄尼醇正交实验的基础上,进一步分析了夹带剂用量、压力和温度影响茄尼醇萃取率的顺序及显著性. 最优强化萃取操作条件为压力25 MPa,温度40℃, 95%乙醇用量为1.5 mL/g. 并通过建立强化萃取茄尼醇的萃取率模型,对最优条件下超临界CO2萃取茄尼醇的萃取率进行预测,预测值为82.4%,与实验均值81.5%基本一致.     

蒙脱石搭载纳米Ni-Fe超声降解十溴二苯醚

为解决传统纳米零价铁（nZVI）降解污染物时易氧化团聚、反应活性低的问题,通过改性手段制备并表征了蒙脱石搭载纳米Ni-Fe（Ni-Fe/蒙脱石）等复合材料,考察污染物和纳米材料质量浓度、温度、溶液初始pH、超声辅助等对其降解十溴二苯醚（BDE-209）的影响,比较nZVI改性前后的降解效果,分析其机理并建立了反应动力学方程。结果表明：最佳反应条件为5mg/L的BDE-209、2g/L的nZVI、温度35℃、pH=3。超声处理10min时BDE-209基本降解完,其表观速率常数（k_obs,0.519min^-1）是震荡处理（0.013min^-1）的40倍、静置处理（0.004min^-1）的130倍。几种材料在10min时对BDE-209的降解率为：Ni-Fe/蒙脱石（99.5%） > nZVI/蒙脱石（85.1%） > 纳米Ni-Fe（64.8%） > nZVI（48.1%） > 蒙脱石（4.1%） > 纳米Ni（1.1%）,120min时k_obs为：Ni-Fe/蒙脱石（0.519min^-1） > nZVI/蒙脱石（0.209min^-1） > 纳米Ni-Fe（0.050min^-1） > nZVI（0.024min^-1）。蒙脱石、纳米Ni及超声本身基本不降解BDE-209。     

Fatty Acid Profile and Bioactive Compound Extraction in Purple Viper's Bugloss Seed Oil Extracted with Green Solvents

Oil extraction from seeds of purple viper's bugloss (Echium plantagineum) was carried out using different solvents (chloroform:methanol, n-hexane, ethanol, 2-propanol and ethyl acetate) at room temperature and also using Randall extraction. Extraction yields were calculated and oils were analyzed in terms of fatty acid profiles and distribution among lipid classes, total polyphenol content, oxygen radical absorbance capacity (ORAC) and phytosterol content. No considerable differences were found on fatty acid profiles and distribution in oils regardless of the solvent and temperature used for the extraction. However, ethanol combined with Randall extraction (85 °C for 1 hour) offered the best results in terms of total polyphenol content (20.9 mg GAE/100 g oil), ORAC (468.0 μmol TE/100 g oil), and phytosterol amount (437.2 mg identified phytosterols/100 g oil) among all assayed extraction methods. A higher extraction temperature led to significantly higher concentrations of bioactive compounds and ORAC values in the oil when ethanol or 2-propanol were used as extracting solvent, but that was not the case using n-hexane except for the concentrations of β-sitosterol and stigmasterol, which were significantly higher using Randall extraction than room temperature extraction with n-hexane. Ethanol is classified as a “green solvent,” and it could be considered a suitable option to produce oil from E. plantagineum seeds with a higher antioxidant capacity and bioactive compound concentration than the current commercial oil, which is usually extracted with n-hexane.     

An evaluation of supercritical fluid extraction as an analytical tool to determine fat in canola,flax, solin,and mustard

Supercritical fluid extraction (SFE) with carbon dioxide was used to extract oil from soft oilseeds (flax, solin, canola, and mustard). Oil content determinations from the SFE method AOCS Am 3–96, with and without ethanol as a modifier, were compared to results obtained with an exhaustive extraction using petroleum ether (FOSFA as in AOCS Am 2–93). Without the modifier, oil recoveries using SFE were 10 to 15% lower than oil contents by the FOSFA method for the flax and canola samples. For mustard, the oil recoveries by SFE were about 20 to 30% lower than oil contents by the FOSFA method. In the presence of the modifier, oil recoveries for flax and canola were about 3% lower than the FOSFA recoveries. Varying the time, temperature, and amount of modifier (ethanol) showed that recoveries increased with time, pressure, temperature, and amount of modifier independently of the oilseeds tested. Kinetics of the SFE extraction showed that the oil recoveries increased with the extraction time and reached a plateau after 60 min. Multiple extractions (2×30 min), however, gave better recoveries than a single extraction for the same amount of time (60 min). The best results were obtained using multiple extractions without modifier or a combination of multiple extractions first without and then with 15% modifier. Under these last two conditions, oil recoveries were close to 100% for flax, solin, and canola, but mustard oil recoveries were still 10% lower than recoveries using the FOSFA method. Mustard samples gave the lowest oil recovery from SFE when compared to FOSFA method recoveries whatever conditions were tested, suggesting a matrix effect on the oil recovery. The acyl lipid content of the various extracts was studied using the sum of all FA expressed as TAG as a measure of acyl lipid extraction. The acyl lipid contents of the extracts were close to 100% when no modifier was used during the SFE. In the presence of modifier, the acyl lipid contents of the extracts were 10 to 15% lower than the results obtained without modifier. The amount of acyl lipid in the extract decreased as the quantity of modifier increased. This suggests that increasing the ethanol modifier increased the amount of polar compounds extracted without significantly increasing the total amount of lipids. The FA profiles were constant throughout the various extraction procedures.     

Extraction of yttrium using naphthenic acid with different acid numbers

Naphthenic acid with acid number of 100–200 mg KOH/g could be used to extract yttrium in the system of 20% naphthenic acid + 20% n-butanol + 60% n-hexane. A transparent and uniform phase was formed during saponification but did not influence the extraction process. n-Butanol and n-hexane could shorten phase separation time and lessen emulsification. Excess naphthenic acid and ammonia, and non-naphthenic acid substances contributed to emulsification and difficulty in phase separation, which were especially serious in system of 20% naphthenic acid + 20% 2-octanol + 60% kerosene. Naphthenic acid with acid number <100 mg KOH/g was unsuitable for extraction in either system. Extraction percentages were 99% and 46% when being saponified by 12.7 and 6.3 mol/L ammonia, respectively.     

咪唑基离子液体萃取分离模拟油酚混合物

酚类化合物(如苯酚、甲酚和二甲酚等)是重要的化工原料和化工中间体,主要来自煤加氢液化油和中低温热解的煤焦油中。目前油中酚类化合物的分离方法主要是碱水洗脱法,这种方法不仅要消耗大量强碱、强酸,而且产生了大量含酚废水,导致分离成本和污染治理费用高,制约了煤液化油和煤焦油中酚类化合物的回收和利用。因此,有必要开发新的分离方法,避免使用酸碱溶液、采用非水相分离方法分离油中的酚类化合物。本文研究发现,卤咪唑基离子液体是一种高效的非水介质,可以用来萃取分离油中的酚类化合物。不同阴、阳离子结构的咪唑基离子液体萃取模拟油中苯酚表明[Bmim]Cl是较好的萃取剂,得因于它能形成较强的分子间相互作用。离子液体的用量与油中酚的量相当,用量少。在20~50℃的萃取温度内,温度对酚的萃取率影响很小。通过加热气提的方法可以使萃取酚后离子液体得到再生,并能重复使用,萃取率几乎不变。进一步将离子液体应用于真实油的酚类化合物的分离表明,咪唑基离子液体[Bmim]Cl萃取酚的效率可达92.5%,是一种具有潜在应用前景的萃取剂。     

A novel organic gas steam-liquid extraction method for the selective extraction of cobalt from water samples

In this work, for the first time, organic gas steam-liquid extraction (OGS-LE) technique was developed as a promotion in the liquid–liquid extraction (LLE) method, by the use of a special homemade extraction cell that was designed to facilitate the traditional LLE method, without emulsification and with high extraction efficiency by a small amount of organic solvent in one step. This method is fast, simple and efficient, and was employed for the selective extraction and determination of cobalt (II) from water samples. The efficiency of the OGS-LE method was compared with the LLE method. The obtained results revealed that by using the OGS-LE technique, the extraction efficiency of cobalt from a synthetic mixture was over 90%, much higher than the traditional LLE method (34%).     

ASE萃取-气相色谱/质谱法测定化妆品包装材料中增塑剂的含量

利用DIONEX ASE350快速溶剂萃取设备提取了化妆品包装材料中可能使用的邻苯二甲酸二丁酯（DBP）、邻苯二甲酸丁基苄基酯（BBP）、邻苯二甲酸二（2-甲氧基）乙酯（DMEP）、邻苯二甲酸二（2-乙基己基）酯（DEHP）、邻苯二甲酸二异辛酯（DI-OP）和邻苯二甲酸二异壬酯（DINP）等六种邻苯二甲酸酯类增塑剂。萃取溶剂为正己烷,萃取温度150℃,压力8 963kPa,驻留时间8min,循环3次,冲洗体积50%,吹扫时间20s。样液经浓缩后采用气相色谱/质谱联用方法测定。试验分析了10个化妆品包装垫片材料样品,发现增塑剂含量范围在0.0024%～1.57%。此方法检测效果良好。     

乙酸仲丁酯在山茶油提取中的应用研究

在食品安全性要求日渐严格的背景下,文章使用不含硫和芳烃的绿色环保溶剂乙酸仲丁酯替代植物油抽提溶剂,实现了山茶油的提取。通过对各影响因素进行系统研究,获得了乙酸仲丁酯作抽提溶剂的最佳工艺参数:温度50℃,3∶1的溶剂比,提取时间为1 h,在该优化条件下的出油率可达到96.7%,明显优于同等条件下的乙酸乙酯、石油醚(60~90℃)、正己烷和乙醇。经简单的减压蒸馏分离回收溶剂,其溶剂残留率为11%,仅比正己烷高出4%。乙酸仲丁酯用以取代植物油抽提溶剂将具有可行性。