Evaluation of H.E.L.P. Mate 2000 for the
Identification and Quantification of
Petroleum Hydrocarbon Products
ALAN D. HEWITT
INTRODUCTION
by the developer of the Hanby Test Kits and the HM
This study evaluates the H.E.L.P. Mate 2000 (HM
2000 analyzer, with help from an assistant (called from
2000), a spectrophotometric device for determining the
here on the technology developer). The same HM 2000
extent and type of total petroleum hydrocarbon (TPH)
system was used for both trials. This report will address
contamination in soil and water matrices. This field-
the ease of use, reliability, accuracy, and the precision
portable instrument was designed to be used in con-
of the HM 2000.
junction with Hanby Test Kits for soil and water sam-
ples. Each matrix-specific test kit contains the neces-
TECHNOLOGY DESCRIPTION
sary reagents and equipment for extracting TPH from
an environmental matrix and for performing a Friedel-
Color chemistry
Crafts reaction that changes the catalyst's color. This
Both the visual and the HM 2000 methods of analysis
method, which is based on a visual inspection of the
assess the intensity of visible colors that are formed
color and intensity of an insoluble catalyst, has been
when aromatic compounds have alkylhalide groups
marketed for the detection and semi-quantification of
attached to them through the Friedel-Crafts alkylation
some aromatic hydrocarbons and TPH.
reaction process. This colorimetric method can be used
The U.S. Environmental Protection Agency's under-
to measure individual aromatic compounds (i.e., benzene,
ground storage tank program (USEPA 1997) acknowl-
toluene, xylenes, etc.) or mixtures, as exist in petroleum
edges the utility of the these field kits, and states that
fuels and oils (i.e., gasoline, diesel fuel, and motor oil).
they are capable of establishing the presence of con-
For petroleum fuels and oils, the resultant color inten-
tamination (i.e., yes/no) and an order of magnitude esti-
sity can be used to estimate the TPH concentration in
mate of concentration. To improve on the data quality,
an environmental sample. The reagents used in the
the manufacturer of these test kits developed a field-
Hanby Test Kits for the Friedel-Crafts alkylation reac-
portable spectrophotometer and data evaluation system,
tion are aluminum trichloride (AlCl3), a strong Lewis
the HM 2000. A direct reading from the HM 2000
acid as the catalyst, and carbon tetrachloride (CCl4) as
should remove the subjectivity associated with visually
the source of alkyl (alkylhalide) groups that are attached
interpreting the catalyst's color for quantification, and
to aromatic hydrocarbons. The electrophilic substitu-
may, in the future, also allow the type of TPH pollution
tion that occurs once the aluminum trichloride is intro-
to be interpreted.
duced results in the formation of very large molecules
The HM 2000 was used to estimate the concentra-
with a high degree of electron dislocation, creating a
tion of TPH in both fortified and field-contaminated
color on the surface of the catalyst.
samples. Laboratory studies were conducted at CRREL,
and the device was demonstrated in the field at the Naval
Soil sample preparation
Construction Battalion Center, Port Hueneme, Califor-
For soils, instructions supplied with the Hanby Test
nia, an Advance Fuel Hydrocarbon National Environ-
Kit recommend placing 5 g into a tared 50-mL beaker
mental Technology Test Site (U.S. Navy 1999). The
and weighing, then adding 10 mL of an extraction
laboratory experiments were performed by the author
solvent composed of 20% carbon tetrachloride/80%
of this report, while the field exercise was conducted
n-heptane (v/v). After 2 to 3 minutes of vigorous stir-
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