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1.
以三油酸甘油酯-醋酸纤维素复合膜(TECAM)萃取作为监测水体中痕量有机氯农药的方法.探讨分析过程中的影响因素和优化条件,结果表明,膜萃取分析方法对17种有机氯农药的平均加标回收率为53%-111%,对强疏水性污染物表现出较高的回收率.利用该方法在南方某自来水厂各工艺段水体中检测出了滴滴涕及其代谢产物、六六六等五种有机氯农药.  相似文献   

2.
贾立明  陈鑫  赵伟  姜波 《环境化学》2014,(12):2228-2230
研究了离子液体双水相萃取分离环境水样中3种酞酸酯类污染物分析方法的可行性,考察了影响离子液体双水相萃取率的主要因素,在最优实验条件下:p H=4,Na H2PO4浓度为0.5 mol·L-1,离子液体加入量为2 m L,萃取时间为6 min,萃取分离了自来水、湖水和工业废水中3种酞酸酯类污染物,液相色谱-串联质谱法测定,回收率为94%—104.2%,相对标准偏差为1.7%—5.3%.方法检出限达0.7—0.99 ng.  相似文献   

3.
加速溶剂萃取的原理及应用   总被引:27,自引:0,他引:27  
牟世芬 《环境化学》2001,20(3):299-300
复杂样品的前处理,常常是现代分析方法的薄弱五一节,在以往的数年中,人们做了多种尝试以期找到一种高效、快捷的方法以取代传统的萃取法,例如,自动索氏萃取、微波消解、超声萃取和超临界萃取等。值得注意的是,以上各法无论是自动索氏萃取,还是超临界流体萃取……等,都有一个共同点,即与温度有关,在萃取过程中,通过适当提高温度,可以获得较好的结果,例如,在自动索氏萃取中,由于萃取时是将样品浸入沸腾的溶剂之中,因此,其萃取速度和效率较常规索氏萃取法快且溶剂用量少,超临界流体萃取可通过提高萃取时的温度使其温度使其回收率得到改善,而微波萃取则是利用一种可以施加压力的容器,将溶剂加热到其沸点之上,来提高其萃取的效率,虽然以上各法与经典的索种可以施加压力的容器,将溶剂加热到其沸点之上,来提高其萃取的效率,虽然以上各法与经典的索氏法相比已有了很大的进步,但有机溶剂的用量仍然偏多,萃取时间较长,萃取效率还不够高。  相似文献   

4.
霍任锋  沈韫芬  徐盈 《环境化学》2004,23(6):695-699
利用顶空固相微萃取(HS-SPME)和气相色谱检测技术,通过对三种不同的SPME萃取头(PDMS,PMPVS,PA)实验条件的优化,并参照液液萃取的方法,对水相中六氯苯,DDT及其代谢产物的萃取效果进行了比较.结果表明,SPME方法比液液萃取方法在检测限和回收率上有很大的提高,其中PDMS对检测六氯苯,DDT及其代谢产物的效果较其它两种萃取头好.  相似文献   

5.
超声波萃取—GC/MS测定大气颗粒物中的多环芳烃   总被引:11,自引:0,他引:11  
采用超声波萃取大气颗粒物样品中的多环芳烃,样品不须纯化,直接可用于GC/MS分析,超声波萃取效率高,萃取时间短;采用MS的SIM方式对多环芳烃进行定性定量,回收率84.5%-108.5%,变异系数3.1%-14.5%。  相似文献   

6.
周黎明  顾惠芬 《环境化学》1995,14(5):449-453
本文对水样中的塔崩及其降解产物磷酸乙酯的提取方法进行了研究,试验了不同的萃取剂及萃取时溶液的pH值,优化了萃取条件,在pH=9时,二氧甲烷萃取塔崩的回收率较高,三次测定的变异系数小于3.0%,用气相色谱-质谱(EI方式)法测定了水样中的塔崩和磷酸乙酯。  相似文献   

7.
磁性介孔硅胶萃取剂的制备及萃取性能研究   总被引:1,自引:0,他引:1  
合成了C18基团修饰的磁性介孔硅胶材料,并利用该材料建立了磁性固相萃取-色谱分析方法,测定了几种环境水样中酞酸酯类(PAEs)污染物的含量.结果表明,该材料具有较大的比表面积(273 m.2g-1)和饱和磁通量(29 emu.g-1),对水样中痕量的PAEs有较强的萃取能力,而且萃取剂的磁分离特性使得萃取操作更为方便、快捷.在优化条件下,30 mg萃取剂在40 min内即可从500 mL水样中萃取痕量PAEs,回收率可达80%以上.此外,该萃取剂在处理复杂环境样品时仍能保持较强的萃取能力,环境水样中4种PAEs的检测限可达15.6—32.5 ng.L-1,加标回收率为62%—109%,相对标准偏差为2%—8%.  相似文献   

8.
建立了一种中空纤维膜液相微萃取的样品前处理技术,结合液相色谱法测定印染废水中芳香胺,并且优化了萃取溶剂、供体相、接收相、搅拌速度、萃取时间等前处理条件.实验结果表明,以正辛醇为萃取溶剂,0.1 mol·L-1Na OH为供体相,0.1 mol·L-1HCl为接收相时,400 r·min-1作为搅拌速度,30 min萃取后的芳香胺富集倍数可达到101—193倍,萃取效率达20.2%—38.6%.结合液相色谱检测芳香胺的线性范围为0.01—0.25 mg·L-1,检出限为1.0—2.0μg·L-1,回收率为95.2%—105.2%.表明该方法可用于检测印染废水中的芳香胺类物质.  相似文献   

9.
马晓国  罗颂华  曾倩 《生态环境》2011,20(12):1909-1911
建立了分散液液微萃取分离富集一石墨炉原子吸收光谱法测定环境水样中痕量镉的新方法。以二乙基二硫代氨基甲酸钠为螯合剂、四氯化碳为萃取剂、丙酮为分散剂,详细考察YpH值、螯合剂质量分数、萃取剂体积、萃取时间等因素的影响。在优化的实验条件下,方法对水样中镉的检出限为4.2ng-L^-1,线性范围是20-300ng-L^-1,测定结果的相对标准偏差为3.5%,富集倍数达103。将建立的方法应用于三种实际环境水样中镉的检测,加标回收率在92%-108%范围内。本方法具有灵敏、准确、快速、环保的特点,是一种分析水样中痕量镉的较好方法。  相似文献   

10.
固相萃取和气相色谱-质谱分析酚类化合物应用简报   总被引:2,自引:0,他引:2  
固相萃取为分析水中痕量化合物提供了简便的分析方法 .高分子树脂如聚苯乙烯 二乙烯基苯比常用的十八烷基和类似的硅胶基体的固相萃取吸附剂好 ,特别是对极性较大的化合物 .最近 ,安捷伦科技扩展了所提供的固相萃取产品 ,包括了聚苯乙烯 二乙烯基苯固相萃取材料AccuBondⅡ ENV小柱 ,专门用于环境应用 .本文用以前介绍的保留时间锁定气相色谱 /质谱分析方法[1 ] ,使用这种聚苯乙烯 二乙烯基苯固相萃取材料对水中浓度为1 0 μg·l- 1 的选定酚类分析能达到的准确度和精密度进行了初步论证 .固相萃取过程快速 ,缩短干燥时间 ,且只需要两种回收率指示物 (Surrogates) .小柱经优化设计 ,提高了酚类化合物的回收率 ,而其它小柱的回收率通常很低且不重复 .苯酚的回收率超过 70 % ,其它酚类化合物的回收率超过 90 % .精密度大于 5 % ,以平均绝对偏差表示的准确度 (以百分数表示 )除了 2 环己基 2 4 二硝基酚之外 ,都大于 8% .样品萃取速率高 (2 0— 2 5ml·min- 1 ) ,萃取 1L样品不到 1h即可完成  相似文献   

11.
2—氨基—5—萘酚—7—磺酸生产废液的资源回用工艺研究   总被引:1,自引:0,他引:1  
本文应用有机胺的离子缔合萃取作用回收了2-氨基-5-萘酚-7-磺酸生产废液中的98%以上的有用成分,结果可从号产品吕废液中获取5723元的净效益,实现了治理资源回收的双重目的。从萃取体系的特性及其影响因素入手,深入研究了萃取剂浓度,待萃物含量及萃取效率的关系,建立了萃取体系的等温方程:1/X/M=7.19+312.91/C,r=0.9997。  相似文献   

12.
采用絮凝-光催化氧化工艺成功地处理了实际染料废水;研究了COD光催化降解动力学。COD和BOD5浓度分别为2169mg/L、295mg/L的染料废水,经絮凝-光催化处理后,出水COD和BOD5分别为214mg/L、18.5mg/L,去除率分别为90.1%、93.7%。向光催化体系中加入H2O2,可促进COD与BOD5的去除。该工艺可处理高浓度染料废水。  相似文献   

13.
The leather industry uses conventional tanning methods which cause environmental pollution due mainly to the presence of chromium. This study suggests a treatment for solid leather waste containing chromium as an ecological alternative to the pollution generated by tanneries. The study uses an original approach to the optimisation of chromium recovery by mathematical and statistical treatment of the experimental data. Several factors that influence recovery, such as temperature, concentration, time and solid/liquid ratio through acid and basic hydrolysis were analysed with the aid of experimental design. Tanning liquor was obtained by adjusting pH, alkalinity and concentration when hydrolysis finished. An appropriate response surface model was constructed using alkaline hydrolysis experiments with sodium hydroxide, leading to conditions for maximum recovery of Cr2O3. The optimal NaOH concentration (1.58%), temperature (63.7 °C), time (3 h) and solid/liquid ratio (1/70 g·mL?1) were established. The results indicate that sodium hydroxide as an hydrolysis agent is a highly efficient means of recovering chromium from solid leather waste in order to produce tanning liquor.  相似文献   

14.
We report the adsorption isotherm of acid dye on the surface of chitin, a unique solid adsorbent. Adsorption process offers an attractive benefit for a dyeing house treatment. Influences of essential kinetic parameters such as adsorbent particle size, reaction temperature governing the dye adsorption have been investigated. Adsorptions isotherms of dye on chitin were developed and the equilibrium data fitted well to the Langmuir, Freundlich and Redlich Peterson isotherm model. At optimum conditions maximum dye adsorption capacity of chitin estimated with the Langmuir 44.0, 85.0, 104.3 mg/g and 85.0, 114.10, 113.62 mg/g adsorbent. The results showed that chelating polymer of chitin could be considered as potential adsorbents for acid dye removal from dilute solution.  相似文献   

15.
蒽醌染料及其中间体絮凝菌的特性   总被引:14,自引:1,他引:13  
本文研究所分离到的真菌NX1对蒽醌染料KNR及其中间体溴氨酸的作用,并考察营养条件、体系PH等对NX1的生长及絮凝作用的影响,结果表明,NZ1及溴氨酸有很好的絮絮凝效果,对PH的适应范围广,最佳碳、氮源分别为蔗粮主尿素。  相似文献   

16.
蒽醌染料及中间体脱色优势菌的特性研究和基因定位   总被引:15,自引:0,他引:15  
宋文华  颜慧 《环境化学》1999,18(3):263-269
本文对分离到的两株蒽醌染料脱色优势菌的脱色能力及其基因定位进行了研究,结果表明,ND1,ND2均能有效脱除活性艳蓝KN-R及溴氨酸的色度;两株优势菌均含有质粒,其降解染料的能力是由质粒控制的;并考察了不同碳源、氧、温度、pH值等理化因素对菌株降解染料的影响。  相似文献   

17.
Removal of congo red dye from water using carbon slurry waste   总被引:1,自引:0,他引:1  
A cheaper adsorbent has been prepared from carbon slurry waste obtained from National Fertilizer Limited (NFL), Panipat and investigated for the removal of congo red, an anionic dye. Its adsorption on prepared carbonaceous adsorbent was studied as a function of contact time, concentration and temperature. The results have shown that carbonaceous adsorbent adsorbs dye to a sufficient extent (272 mg g-1). A comparative study of adsorption results with those obtained on activated charcoal shows that the carbonaceous adsorbent is ~95% efficient as compared to activated charcoal. Thus, it can be fruitfully used for the removal of dyes from wastewaters.This work has been presented at the National Symposium on Biochemical Sciences: Health and Environmental Aspects (BSHEA—2003), Agra, India (2003).  相似文献   

18.
酸性染料的臭氧降解与中间产物   总被引:4,自引:0,他引:4  
以酸性金黄G模拟染料废水为研究对象,观察臭氧氧化过程中染料溶液吸光度和TOC的变化,利用离子色谱仪、红外光谱仪和GC/MS对染料的降解过程进行了分析,并用发光细菌法检测了溶液急性毒性的变化,结果表明,臭氧对染料的降解符合一级反应动力学,反应40 min后染料溶液的脱色率达到99.3%,TOC去除率为35.7%;染料分子中的S有97.8%被转化为SO2-4,分子中的仲胺基部分转化成酰胺基,水解后生成NH+4,最终氧化成NO-3,溶液中有草酸产生;溶液在臭氧化前期由于生成了醛类和酚类物质,使急性毒性首先呈上升趋势,25min后随着氧化的深入,溶液毒性开始逐渐下降,  相似文献   

19.
Several synthetic dyes employed in textile and food industries are discharged into aquatic environment. These visible pollutants in water damage environment, as they are carcinogenic and toxic to humans. The use of cost effective and ecofriendly plant cellulose based adsorbents have been studied in batch experiments as an alternative and effective substitution of activated carbon for the removal of toxic dyes from waste water. Adsorbents prepared from sugarcane baggase, were successfully used to remove certain textile dye such as crystal violet from an aqueous solution. The present investigation potentiate the use of sugarcane baggase, pretreated with formaldehyde (referred as Raw Baggase) and sulphuric acid (referred as Chemically Activated Baggase), for the removal of crystal violet dye from simulated waste water. Experiments were carried out at neutral pH with various parameters like dye concentration, temperature, contact time and adsorbent dosage. Efficiency of raw baggase was found better than chemically activated baggase for adsorption of crystal violet dye. The data obtained perfectly fits in the Freundlich adsorption isotherm.  相似文献   

20.
A new polymeric resin with amino sulfonic acid pendant functions has been prepared for the extraction of acidic and basic dyes from water. Beaded polymer supports were prepared by suspension polymerization of vinyl benzyl chloride (0.9 mol) and ethylene glycol dimethacrylate (0.1 mol). The resulting copolymer beads were modified with amino methane sulfonic acid. The dye adsorption capacity of the resin was found as 0.16 g dye/g resin for ramazol black and 0.15 g dye/g resin for crystal violet. The pH depending measurements and dye sorption kinetics of the resin were also investigated.  相似文献   

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