Page:NIOSH Manual of Analytical Methods - 2529.pdf/4

 FURFURAL: METHOD 2529, Issue 2, dated 15 August 1994 - Page 4 of 4 REFERENCES: [1] E. R. Kennedy, Y. T. Gagnon, J. R. Okenfuss and A. W. Teass, "The determination in air of selected low-molecular weight aldehydes as their oxazolidines by capillary gas chromatography." Appl. Ind. Hyg., 3, 274-279 (1988). [2] NIOSH Manual of Analytical Methods, 2nd ed., Vol. 4, S17, U.S. Department of Health, Education, and Welfare, Publ. (NIOSH) 78-175 (1978). [3] NIOSH/OSHA Occupational Health Guidelines for Chemical Hazards, U.S. Department of Health and Human Services, Publ. (NIOSH) 81-123 (1981), available as Stock #PB83-154609 from NTIS, Springfield, VA 22161. [4] The Merck Index, 10th ed., Merck & Co., Rahway, NJ (1983). [5] Kennedy, E. R. and R. H. Hill, Jr. "Determination of Formaldehyde in Air as an Oxazolidine Derivative by Capillary Gas Chromatography," Anal. Chem., 54, 1739-1741 (1982). [6] Lipari, F. and S. J. Swarin. "Determination of Formaldehyde and other Aldehydes in Automobile Exhaust with an Improved 2,4-Dinitrophenylhydrazine Method", J. Chromatog ., 247, 297-306, (1982).

METHOD REVISED BY: Julie R. Okenfuss and Eugene R. Kennedy, Ph.D., NIOSH/DPSE.

APPENDIX: SORBENT PREPARATION (optional if commercially prepared tubes are used): Add 1 g purified 2-(hydroxymethyl)piperidine in 50 mL toluene for each 9 g extracted XAD-2 sorbent. Allow this mixture to stand 1 hr with occasional swirling. Remove the solvent by rotary evaporation at 37 °C and dry at 130 Pa (1 mm Hg) at ambient temperature for approximately 1 hr. To determine the amount of background for each batch, desorb several 120-mg portions of the coated sorbent with toluene and analyze (steps 7 through 13). No blank peak is expected for furfural. SYNTHESIS OF FURFURAL OXAZOLIDINE [1]: Place a solution of 0.58 g (0.5 mL; 6 mmol) freshly distilled furfural in 10 mL toluene in a 50-mL round-bottomed flask. Add 2.5 g magnesium sulfate to the flask to remove water which forms during the reaction. Add a solution of 0.61 g (5.3 mmol) purified 2-hydroxymethylpiperidine in 10 mL toluene dropwise with stirring over 1 hr. Stir the solution overnight, then filter to remove the magnesium sulfate. Remove the toluene from the solution at reduced pressure by rotary evaporation. The product is a yellow viscous oil. DESORPTION EFFICIENCY : The determination of desorption efficiency (DE) is not necessary when using the calibration procedure in step 10. If desired, the following procedure can be used to determine DE: a. Prepare and analyze a set of oxazolidine standard solutions (step 9.a) and a set of working standards (step 10) including media blanks. b. Treating the working standards as unknowns, read the mass (mg) of oxazolidine found in each working standard (W), and in the average media blank (B). c. Using the mass of furfural, mg, spiked onto the working standard (W o) and the stoichiometric conversion factor between furfural and furfural oxazolidine (2.01), calculate the desorption efficiency:

d. Prepare a graph of DE vs. µg furfural recovered per sample [(W - B)/2.01].

NIOSH Manual of Analytical Methods (NMAM), Fourth Edition, 8/15/94