MINORITY/LOW INCOME STUDENTS SCIENCE RESEARCH

MENTORING PROGRAM

Asopuru Okemgboa Washington State University Tri-Cities 2710 University Drive Richland, WA 99354

aCH2M Hill Hanford, Inc.

Richland, WA 99352

Whitney Harris1

Guadalupe Contreras2 ACS Project SEED Interns

1Kennewick High School

2Pasco High School

Research Report

Evaluation of Solid Phase Extraction/GC-FID of Phenols in

Synthetic Hanford Waste

Guadalupe Contreras (Presenter)

Pasco High School, Pasco

Analytical Chemistry Lab

Objectives

To investigate the extraction of phenols in high alkaline synthetic Hanford waste (SHW) using various commercially available solid phase extraction sorbent.

To evaluate the effects of ion-pairing reagent in the isolation of phenols from high basic synthetic Hanford waste.

Hanford Tank Waste

– Nuclear waste accumulated between1944 and 1987 was one of the aftermaths of World War II and Cold War nuclear bomb production.

– It is the biggest US environmental restoration, waste management, and waste treatment project.

– A $5.8 billion DOE Waste Treatment Project under construction.

Hanford Site Background

Hanford Underground Tanks

•149 Single Shell Tanks (SST’s)- Built 1943-1964.- Capacity of 55,000 to 1 million gal.

• 28 Double Shell Tanks (DST’s)- Built 1966-1986.- Capacity of 1.25 million gal. each.

• Contains about 54 million gal. Waste.

At the Hanford Site, tank waste clean-up, waste treatment, tank closure, and environmental restoration are the highest priorities of the Department of Energy.

Characterization of the waste is a very important step towards meeting these goals.

EPA methods have not been amenable to the measurement of phenols in basic aqueous sample.

There is, therefore, no suitable method to measure them.

This method development project will be a major contribution to the waste characterization of the Hanford nuclear waste.

Background and Significance

Sample Prep for Synthetic Hanford Waste

To 5mL of synthetic Hanford waste add 100μg/L of phenols

Add 2mL of PIC-A reagent Extract with SPE sorbent (Strata-X from

Phenomenex, Nexus from Varians, Oasis from Waters)

Elute with 2mL of methanol Inject 2μL into GC

GC Conditions

Initial Oven Temperature Ramp Rate: Final Temperature Injection Temperature

Detector Temperature Run Time Carrier gas Carrier Flow

70°C 10°C/min 280°C 300°C 350°C 21 min. He 1.9mL/min

Chromatogram of Phenols Standard

phenol1, 2-chlorophenol2, 2-nitrophenol3, 2,4-dimethylphenol4, 2,4-dichlorophenol5, 4-chloro-3-methylphenol6, 3-nitro-o-xylene7, 2,4,6-trichlorophenol8, 2,4-dintrophenol9, 2,3,4,5-tetrachlorophenol10, 2,4,6-tribromophenol11

1

2

9

6

8

11

57

10

4

3

Chromatogram of PIC-A Reagent Blank

Chromatogram of phenols in SHW treated with PIC-A

Strata-X sorbent

9

6

8 114

2

Chromatogram of phenols in SHW not treated with PIC-A

Strata-X sorbent

6

9

5

Chromatogram of phenols in SHW treated with PIC-A

Nexus sorbent

9

106

Chromatogram of phenols in SHW treated with PIC-A

Oasis sorbent

11

9

612

48

10

Conclusion

Solid phase extraction of phenols in highly basic synthetic Hanford waste afforded analyte isolation with small sample size, minimum sample prep, and elimination of large volumes of hazardous organic solvents commonly used in liquid-liquid extraction methods.

Preliminary data from using PIC-A reagent suggest improved recovery of phenols from high alkaline synthetic Hanford waste.

Additional work required to optimize the method.

Acknowledgements ACS Project SEED Interns

– Whitney Harris, Kennewick High School

– Guadalupe Contreras, Pasco High School

ACS Project SEED Program MSRM Matching Fund Donors

– Dr. Andy Ward– Dr. Feyi Ward– Dr. P.S. Sundar– Riverside Rotary Club– Northwest Agricultural Products– MESA WSU Tri-Cities– WSU Tri-Cities

CH2M Hill Hanford, Incorporated