Polyurethane foam soxhlet extraction

Ai r Collection on particulate filter and polyurethane foam Soxhlet extraction alumina column clean-up GC/ECD 0.1 ng/m3 >95... 

Air (CDDs) Drawing of approximately 325 m3 of air through quartz fiber filter/polyurethane foam Soxhlet extraction with benzene, volume reduction clean-up using silica, alumina, activated carbon volume reduction addition of [13C12]2,3,7,8-TCDD. HRGC/HRMS MID (EPA TO-9) 1-5 pg/m3 68-140 from ultra pure, filtered air EPA1988g... 

Air, gloves (surrogate for dermal exposure) Preconcentration from air sample using polyurethane foam (PUF). Soxhlet extraction of PUF or gloves with 5% ethyl ether/hexane. Addition of deuterated internal standards and concentration using K-D and nitrogen blowdown. Capillary GC/MS (can use multiple ion detection) 55 ng/m3 (5.5 nr sample) 73 (14% RSD) Hsu et al. 1988... 

Diazinon has a finite vapor pressure (see Chapter 3) and thus will be present in the air. A method for diazinon in air has been reported that is based on the use of polyurethane foam (PUF) to adsorb the pesticide from the air as the air is pulled through the PUF (Hsu et al. 1988). The PUF is then Soxhlet-extracted and the extract volume reduced prior to capillary GC/MS analysis. An LOD of 55 ng/m3 (5.5 m3 sample) and recovery of 73% were reported. Another study was described in which the diazinon levels in indoor air were monitored following periodic application of the pesticide for insect control (Williams et al. 1987). In this method, air is pulled through a commercially available adsorbent tube to concentrate diazinon. The tube is then extracted with acetone prior to GC/NPD analysis. No data were provided for the LOD, but recoveries in excess of 90% were reported at the 0.1 and 1 pg/m3 levels. This paper also indicated that diazinon can be converted to diazoxon by ozone and NOx in the air during the sampling process. 

The resins and the carbon-impregnated polyurethane foam were separately placed in cellulose thimbles and Soxhlet extracted successively for 24 h with HPLC-grade hexane, dichloromethane, acetone, and methanol. The final methanol extract from each adsorbent was concentrated and analyzed by GC by using the FID. 

Air (hazardous waste site) (2,3,7,8-TCDD) Collection of sample onto glass fiber filter/polyurethane foam cartridge add [37CI4]2,3,7,8-TCDD and [13C12]2,3,7,8-TCDD Soxhlet extraction with CH2CI2 clean-up with acid/base sequentially on silica gel, modified silica gel, alumina, and carbon HRGC/LRMS No data 0.02 pg/m3 91-112 74-112 Fairless et al. 1987 Harless et al. 1992... 

Air (CDDs) Collection of sample onto glass fiber filter/polyurethane foam cartridge addition of internal standard Soxhlet extraction with toluene volume reduction clean-up and fractionation on Florisil , elutiion with toluene/diethylether, evaporation and redissollution in cyclohexane clean-up on modified silica gel using HPLC and hexane/diethyl ether volume reduction HRGC/LRMS (EI/SIM) HRGC/LRMS (NCI/SIM) 0.1-1 pg/m3 0.2-3 pg/inj (0.01-0.1 pg/m3) 80-122 86-102 Oehme et al. 1986... 

Air (CDDs) Collection of sample onto quartz fiber/polyurethane foam plug Soxhlet extraction with acetone clean-up with hexane and sulfuric acid followed by silica gel and alumina columns HRGC/MS (SIM) 0.5 pg/m3 70-90 Kuwata et al. 1993... 

Air Collected on XAD-2 resin sandwiched between polyurethane foam plugs, Soxhlet extracted with 6% ether/hexane GC/MS 1.0691 g / extract 114 Rudel et al. 2001... 

The sample was collected using a high-volume air sampler, in which 13,000 m of air was sampled over a 7-day period. Air was aspirated through a glass fiber filter and two polyurethane foam plugs. Samples were subjected to Soxhlet extraction... 

Horn (1993) investigated dichlofluanid, furmecyclox, IPBC, tebuconazole and per-methrine in a 1-m glass chamber. The loading was 1 mVm and air exchange was 1 h" . Temperature and relative humidity were 23 °C and 45 %, respectively. After testing suitability of silica gel, active charcoal, polyurethane foam (PUF), XAD-4 and Tenax he chose PUF for sampling followed by Soxhlet extraction for 6 h with 5 % diethyl ether in n-hexane. Analysis was done by GC-ECD and GC-FID. 

Polyurethane foam (PUF) (VDI 3498, Part 1, 1998) This is made of toluene diisocyanate (TDI) and polyoxypropylenetriol with a density of 25 kg/m or TDI-polyether foam with a density of 33 kg/m cut into cylinders of 50 mm length and 110 mm diameter. For clean-up, the foam is extracted in a Soxhlet apparatus with toluene (24 h) and acetone (24 h). The PUF is then placed in a vacuum oven and dried at room temperature under nitrogen atmosphere. 

Extraction aims to recover as much as possible of the pollutants from the sampling material. So it is a very fundamental aspect in the analytical process (Yusa et al. 2009). The extraction of POPs in air can be achieved through several established methods (Hawthorne et al. 1989 Chee et al. 1997 Lenicek et al. 2000 Yeo et al. 2003 Christensen et al. 2005). USEPA method 3542 (Soxhlet extraction) has been used to extract semi-volatile organic pollutants from air samples such as filters, XAD-2 resin or polyurethane foam (PUF). Sonication is also one of the extraction methods mostly used to prepare air samples for determination of POPs. All of these traditional procedures have some weaknesses of large volumes... 

Atmosphere adsorption on polyurethane foam (desorption by Soxhlet extraction with petroleum ether) alumina fractionation (elution with 2 1 MeOH/ CH2CI2) water. SPE on XAD-2 resin Matrix solid phase dispersion extraction with Cijj (MeOH elution) AI2O3 cleanup of MeOH eluate SPE on poly(styrene/divinylbenzene) disk (elution with acetone, MeCl2, hexane) NP-HPLC fractionation Water. SPE on Cig (acetone elution) sediment and algae Soxhlet extraction with hexane cleanup by SPE NH2 media (elution with 75 25 hexane/acetone)... 

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