Volume polyurethane foams

TO-4 High volume Polyurethane foam sampling, GC/ECD analysis Chlorinated pesticides and PCBs... 

TO-9 High volume Polyurethane foam sampling with High Resolution GC/High Resolution MS (HRGC/HRMS) analysis Polychlorinated dibenzo-p-dioxin... 

Method EPA TO 4, Determination of Pesticides and Polychlorinated Biphenyls In Ambient Air Using High Volume Polyurethane Foam (PUF) Sampling Followed By Gas Chromatography/Multidetector, US EPA. 

Method EPA TO 4, Determination of pesticides and polychlorinated biphenyls in ambient air using high volume polyurethane foam (PUF) sampling followed by Gas Chromatographic/Multidetector U.S. Environmental Protection Agency. 

EPA, Compendium Method TO-lOA Determination of pesticides and polychlorinated biphenyls in ambient air using low volume polyurethane foam (PUF) sampling followed by gas chromatographic/multi-detector detection (GC/MD), pp. 37, in Compendium of Methods for the Determination of Toxic Organic Compounds in Ambient Air, 2nd ed., Cincinnati, OH Center for Environmental Research Information, Office of Research and Development, U.S. Environmental Protection Agency, 1999. 

D. A. Glowka, G. E. Loeppke, P. B. Rand, and E. K. Wright. Laboratory and field evaluation of polyurethane foam for lost circulation control, volume 13 of The geysers—three decades of achievement A window on the future, pages 517-524. Geothermal Resources Council, Davis, CA, 1989. 

Surface Adsorption Hater sample is passed through a column of the adsorbent and the adsorbed organic constituents subsequently eluted with a smaller volume of organic solvent. All sample types Adsorbents Include charcoal, macroretlcular resins, polyurethane foams, bonded phases and ion-exchangers. Generally have high capacity but sample discrimination may be a -problem. Sample modification and Incomplete recovery are further possible problems. 

Sample collected with low-volume sampler consisting of a constant flow pump and a cartridge containing polyurethane foam. Extract with diethyl ether in hexane. 

Thrane, K. E., and A. Mikalsen, High-Volume Sampling of Airborne Polycyclic Aromatic Hydrocarbons Using Glass Fiber Filters and Polyurethane Foam, Atmos. Environ., 15, 909-918 (1981). 

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. 

In a second example, Storey et al. demonstrated that one could covalently immobilize amyloglucosidase using hydrophilic prepolymers. A 5-mg/ml solution of the enzyme was mixed with an equal volume of prepolymer. The method was judged superior as a support for enzyme immobilization. The percent activity inuno-bili/ed in the polyurethane foams was 25 1.5%. 

Tuerker and Mavituna immobilized Trichoderma reesei within the open porous networks of reticulated polyurethane foam matrices. Growth pattern, glucose consumption, and cellulase production were compared with those of freely suspended cells. The method of immobilization was simple and had no detrimental effect on cell activity. Hundreds of similar projects could be cited. Not all rated the use of polymethane as the preferred technique. If a statistical analysis were conducted on aU the immobilization literature, we are sure that no single technique would be dominant. However, the combination of ease of immobilization, cost of materials, flow-through properties, control of flux rate through the immobilizing membrane, high surface-to-volume ratio, and other factors make polymethane a viable substratum for the continuous production of proteins. 

Air analysis may be performed by U.S.EPA Method TO 13 (U.S.EPA 1988), which is quite similar to the above method. PAH-bound particles and vapors (many compounds may partially volatilize after collection) may be trapped on a filter and adsorbent (XAD-2, Tenax, or polyurethane foam), and then desorbed with a solvent. The solvent extract is then concentrated and analyzed by HPLC (UV/Fluorescence detection), GC-FID, or GC/MS (preferably in SIM mode). Because of very low level of detection required for many carcinogenic PAHs, including benzo(a)pyrene, the method suggests the sampling of a very high volume of air (more than 300,000 L). 

Most of the organochlorine pesticides listed in this chapter may be analyzed by NIOSH and U.S. EPA Methods (U.S. EPA 1984-1988, NIOSH, 1984-1989). The method of analysis, in general, involves drawing a measured volume of air through a sorbent cartridge containing polyurethane foam or Chromosorb 102. The pesticides are extracted with an organic solvent such as toluene, hexane, or diethyl ether the extract concentrated and analyzed by GC-ECD. The extract may be cleaned up by florisil to remove any interference (U.S. EPA Method 608). 

Recommended Method Airborne particles collected on a sorbent cartridge containing polyurethane foam extracted with 5% diethyl ether in hexane extract analyzed by GC-ECD recommended air flow 5 L/min sample volume 1000 L. 

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 (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... 

Uses The technical-grade dinitrotoluene is an oily liquid and is easily combustible. Essentially, dinitrotoluene is used in large volume during the manufacture of polyurethane foams and polymers, in the production of toluene diisocyanates, and in manufacturing explosives. 

Table I. Pesticide Vapor Sampling Efficiencies of XAD-4 Resin and Polyurethane Foam in a High Volume Air Sampler3,b...

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