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1.
闫彩辉  赵炜  刘丹  吴晓娜  杨华美  赵婧  陶鑫  盛晨 《化工进展》2012,31(1):57-61,82
采用微波辅助条件下热解稀硫酸预处理的麦秆制取生物油,产物采用分级萃取进行固液分离,依次分离出了环己烷萃取物、乙酸乙酯萃取物、甲醇萃取物和四氢呋喃萃取物,并用气相色谱/质谱联用仪(GC/MS)分析了各级萃取物。结果表明,本研究制取的生物油中化合物种类较少,有利于生物油中高附加值化学品的分离,其中5,6-二氢吡喃-2-酮在环己烷萃取物中的相对含量为45.0%,糠醛在生物油总产物中的相对含量为45.6%。此外,生物油中酸的相对含量为16.0%,表明该生物油含酸量高而不易于直接作为燃料油使用。  相似文献   

2.
介绍了GC/MS联用仪对高硫高酸原油废水可二氯甲烷萃取的有机组分进行分离、定性的检测方法,并对高硫高酸原油废水进行了常规项目分析。结果表明:高硫高酸原油混合废水的COD高达804 mg/L,其中有机组分占93.6%(以COD计),有机物种类达57种,其中主要是酚类化合物。  相似文献   

3.
魏晴 《化工时刊》2013,(9):9-12
在超声辐射下用等体积的水萃取了稻壳生物油,离心分离后得到水溶物,并对水溶物依次用石油醚、CS2、CCl4、氯仿和丙酮进行萃取,分析发现得到的丙酮萃取物(E0)萃取率很高,但在气相色谱/质谱联用仪(GC/MS)上不显示化合物信息。为提高E0的利用效率,以TiO2作为催化剂,考察了温和条件下该生物油水溶组分丙酮萃取物的光催化氧化反应。通过活性炭吸附从反应混合物中分离了有机成分并依次用石油醚和丙酮萃取,得到萃取物1和2(E1和E2),继而用GC/MS分析了E1和E2。结果表明,在E1和E2中检测到大量的酚类、酸类、酮类和酯类等含氧化合物,且多为羟基和烷氧基取代物,这对生物油的高效利用具有重要意义。  相似文献   

4.
向群  龚勇 《广东化工》2011,38(11):218-219,221
以氯化钾和磷酸为原料,利用有机溶剂萃取法制备磷酸二氢钾的新工艺。选择了萃取率高、易回收的有机萃取剂三正丁胺作为萃取剂。考察了原料液中加水量、萃取时间、萃取剂用量、萃取温度对产品产率和纯度的影响。实验结果表明:较好的工艺条件为萃取剂用量为40 mL,萃取时间为40 min,用水量为20 mL,萃取温度为30℃,得到的磷酸二氢钾产品的产率高达96.426%和纯度高达98.252%。  相似文献   

5.
吕东灿  刘运权  王夺  袁亮 《化工进展》2012,31(7):1425-1431
综述了国内外采用萃取技术分离生物油的研究进展,包括水萃取、有机溶剂萃取、络合萃取、超临界萃取、柱层析萃取等,总结了这些萃取方法的优点和缺点。指出可通过对生物质热解过程本身进行改进,如对原料进行预处理、引入催化剂进行催化热解、对热解蒸汽进行分级冷凝等,以获得富含目的产物组成的生物油,为萃取分离提供便利。最后,建议尝试一些新的萃取分离方法,如微波萃取和超声波萃取等,考察对生物油萃取分离的有效性。  相似文献   

6.
用碱皂化塔尔油沥青后用有机溶剂提取。结晶分离植物甾醇,经重结晶,提高植物甾醇的纯度。该方法可提取9.8%(以塔尔油沥青计)植物甾醇,经一次重结晶纯度可达93.2%。  相似文献   

7.
混凝-纳滤预处理环氧树脂废水的研究   总被引:2,自引:0,他引:2  
本文针对环氧树脂生产废水采用FeSO4、PAM、有机改性膨润土等进行混凝强化预处理,再用纳滤膜分离技术对预处理水中有机物和盐进行分离回用.结果表明:以FeSO4或PAM为混凝剂单独作用时,COD最佳去除率为28%;两者结合COD总去除率可达40%;利用膨润土原土作吸附剂,总去除率最高为32%;采用有机膨润土吸附,COD去除率可达到72%.预处理脱盐率仅为8.7%.强化预处理以后,采用两级纳滤膜分离技术,出水的含盐量从48.54g/L降至低于10g,L,大大降低了高含盐对有机废水后续生物处理的影响.  相似文献   

8.
以一种褐煤和一种煤焦油为原料,在高压釜中进行加氢反应,正己烷萃取液相产物,碱抽提法富集萃取物中的酚类化合物并进行GC/MS分析.结果表明,在褐煤液化油体系中共鉴定出24种酚类化合物,在煤焦油加氢体系总共鉴定出21种酚类化合物,煤基油中酚类化合物包含苯酚、茚满酚和萘满酚,高级酚含量居多.煤基油中多数酚类化合物含有烷基侧链,3及3以上碳数的侧链构成多样复杂.  相似文献   

9.
为了克服传统柱色谱法的缺点,达到从金银花中分离富集绿原酸的目的,利用V(乙醇):V(乙酸乙酯)=9:91混合有机溶剂选择性萃取方法,从金银花浸膏中富集得到绿原酸萃取液,经过简单活性炭吸附除杂、减压蒸馏浓缩和重结晶得到绿原酸晶体。绿原酸的萃取率约为36.63%,纯度达98.63%。这为分离纯化绿原酸提供了一种简单高效的液-液萃取方法。  相似文献   

10.
煤直接转化液体产物中除含有大量的酚类化合物外,还含有一些其他含氧含氮化合物,这些物质对于酚的萃取分离具有重要影响。采用乙二醇-尿素复配溶剂作为萃取剂,考察了萃取剂中尿素含量、搅拌时间、静置时间、温度以及萃取剂使用量对煤直接转化液体产物模拟油中酚类化合物萃取效果的影响,探究了模拟油中杂原子化合物苯乙酮、吲哚、吡啶对酚类分离效果的影响。结果表明:乙二醇-尿素复配溶剂对间甲酚的萃取效果要明显优于尿素,搅拌时间为20 min,静置时间为10 min时就可达到萃取平衡,升高温度不利于萃取,间甲酚萃取率随着萃取剂使用量的增加呈现先增加后趋于平缓的趋势,当温度为25℃、m(萃取剂):m(模拟油)(剂油比)为1:1时,乙二醇-尿素复配溶剂对间甲酚萃取率可达99.2%;模拟油中添加苯乙酮、吲哚、吡啶均会降低萃取剂对间甲酚的萃取率,相对于苯乙酮和吲哚,吡啶对间甲酚分离影响最大,可使间甲酚萃取率降低到71.6%。  相似文献   

11.
低温煤焦油组分的分离对其充分利用具有重要的作用。分别以正十二烷、甲苯和苯酚为模型化合物,采用实验和Aspen Plus模拟两种方法得到了低温煤焦油中脂肪烃-芳烃-酚类三元体系的液液平衡关系,并模拟了N,N-二甲基甲酰胺(DMF)水溶液萃取分离该体系时的典型三元相图。结果表明,Aspen Plus采用UNIF-LL法模拟得到的三元相图与实验测定结果吻合较好。甲苯在正十二烷-甲苯-苯酚体系中作为共溶溶剂,促使三元体系成为均相。根据正十二烷、甲苯和苯酚在DMF中的溶解性差异,结合Hansen溶度参数理论,通过在DMF中添加不同含量的H2O以调节萃取剂的极性,可使正十二烷和甲苯依次从均相体系中分离。通过对萃取温度、剂油比和萃取剂含水量进行优化,最终在303.15 K,剂油比为1.5时,以DMF对模型油进行单级萃取,可以得到纯度为93.2%的正十二烷;相分离后向萃取相中添加DMF量30%的H2O,可分离出纯度为93.4%的甲苯。  相似文献   

12.
Abstract

The non-sulfonated oil in industrial petroleum sulfonate was separated by centrifugal method and extraction method, respectively. The oil separation rates of each method were compared, and the effects of oil separation rates under different conditions on the purity of non-sulfonated oil were investigated. The purity information of non-sulfonated oil separated by different methods was analyzed by infrared spectroscopy. The experimental results showed that the oil separation rate of centrifugation was low, and the oil extraction rate was higher. The purity of non-sulfonated oil separated with alcohol–water solution as extractant was lower, while the purity of non-sulfonated oil separated by water extraction method was the highest, and the extractant was nontoxic and environmentally friendly. Water was preferred as extractant. Solvent ratio, temperature and pressure all had great influence on oil separation rate. The optimum conditions for SL petroleum sulfonate were: solvent ratio 1.5:1, 90?°C, atmospheric pressure, which the oil separation rate was 78.51%; and for DQ petroleum sulfonate, the optimum conditions were: solvent ratio 2:1, 90?°C, atmospheric pressure, which the oil separation rate was 79.86%. Non-sulfonated oil separated by water extraction had the least petroleum sulfonate, followed by ethanol single solvent extraction. Although the extraction efficiency of isopropanol aqueous solution and n-pentane was the highest, the content of petroleum sulfonate in non-sulfonated oil was the highest, which affected the product performance and should not be used.  相似文献   

13.
《分离科学与技术》2012,47(13):1986-1992
In this study, it was aimed to extract phenolic compounds from caper by using microwave and to compare the results with conventional extraction. For microwave-assisted extraction, power, extraction time, solid to solvent ratio, and solvent type were selected as independent variables. Dependent variables were total phenolic content (TPC), antioxidant activity, and concentration of phenolic compounds. The increase in solvent amount increased TPC. The highest TPC was obtained by using extraction conditions of 5 min at 400 W, solid to solvent ratio of 1:30, and ethanol-water mixture at a ratio of 50:50. There was no significant difference between microwave and conventional extraction on TPC and antioxidant activity (AA). However, microwave-assisted extraction decreased extraction time significantly.  相似文献   

14.
《分离科学与技术》2012,47(15):3397-3408
Abstract

The essential oil was obtained by supercritical fluid extraction from dried roots of Ligusticum chuanxiong. Different solvent systems for high‐speed counter‐current chromatography (HSCCC) were compared. A system composed of n hexane–ethyl acetate–methanol–water–acetonitrile in the ratio of 8:2:5:5:3 (v/v) was found to be optimum for HSCCC of the essential oil. Z ligustilide and senkyunolide A were separated by HSCCC with purity of 98% determined by GC. The chemical structures of these two components were identified by nuclear magnetic resonance (NMR) and mass spectrometry (MS).  相似文献   

15.
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。  相似文献   

16.
This work explored the potential of subcritical liquids and supercritical carbon dioxide (CO2) in the recovery of extracts containing phenolic compounds, antioxidants and anthocyanins from residues of blueberry (Vaccinium myrtillus L.) processing. Supercritical CO2 and pressurized liquids are alternatives to the use of toxic organic solvents or extraction methods that apply high temperatures. Blueberry is the fruit with the highest antioxidant and polyphenol content, which is present in both peel and pulp. In the extraction with pressurized liquids (PLE), water, ethanol and acetone were used at different proportions, with temperature, pressure and solvent flow rate kept constant at 40 °C, 20 MPa and 10 ml/min, respectively. The extracts were analyzed and the highest antioxidant activities and phenolic contents were found in the extracts obtained with pure ethanol and ethanol + water. The highest concentrations of anthocyanins were recovered with acidified water as solvent. In supercritical fluid extraction (SFE) with CO2, water, acidified water, and ethanol were used as modifiers, and the best condition for all functional components evaluated was SFE with 90% CO2, 5% water, and 5% ethanol. Sixteen anthocyanins were identified and quantified by ultra performance liquid chromatography (UPLC).  相似文献   

17.
[omim]BF4离子液体萃取酚类化合物的研究   总被引:4,自引:3,他引:1  
采用水浴微波法合成离子液体萃取剂[omim]BF4.研究[omim]BF4对苯酚、邻甲酚等7种酚类化合物的萃取,考察了萃取时间、温度、相比及pH值对萃取效果的影响.实验结果表明:萃取10 min就可以达到平衡;随着温度升高或[omim]BF4与含酚水溶液相比的降低,分配系数降低;酚溶液在pH< pKa时,即酚类化合物主要以分子状态存在时,萃取效率较高.与萃取剂[bmim]PF6及传统有机溶剂相比,[omim]BF4萃取酚类化合物的分配系数处在同一数量级.同时对[omim]BF4萃取酚类化合物的机理进行了探讨,离子液体中的氟与酚类化合物的羟基形成了氢键.  相似文献   

18.
This study analyzes polycyclic aromatic hydrocarbon (PAH) compounds released from scrap tires by GC/MS and introduces a simple extraction process at ambient conditions to remove PAHs from scrap tires. The PAH species released from scrap tires included seven PAH compounds with high molecular weight and 4- and 5-aromatic rings and total-PAH content of 159 mg/L. When scrap tires were extracted using hot water (180 °C) for 3 h, the overall removal efficiency was 53%, indicating that PAHs were not adequately removed by this method. However, using organic solvents, the overall PAH removal efficiency improved to 82% for propionic acid and 70% for acetic acid, because the mass transfer of PAHs within scrap tires increases with decreasing dielectric constant. The PAH removal efficiency was dependent on solvent type and temperature.  相似文献   

19.
α-磺基脂肪酸甲酯钠盐(MES)产品(含活性物质70%)在加热熔融的状态下滴加到50~55℃低沸点水溶性有机溶剂中,经冷却、结晶、过滤和干燥,得到高纯MES粉剂产品。考察了低沸点水溶性有机溶剂种类、原料与溶剂的投料质量比、冷却温度和结晶时间等工艺条件对产品回收率、活性物质量分数和过筛率的影响,得到了最佳纯化精制工艺:以甲醇为溶剂,5 kg MES,MES与溶剂的投料质量比为1:3,冷却温度为5℃,结晶时间为120 min,干燥时间60 min,干燥温度45℃,溶剂使用3次。本工艺条件下,所制得MES粉剂产品回收率大于98%,含活性物质量分数大于93.0%,产品在40℃密封保存12 h后,过0.850 mm筛孔的筛,过筛率达100%。  相似文献   

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