Petroleum products

1. Analysis Of Petroleum And Petroleum
Products : Instruments And Technique
By
Karuna D. Gaikwad
Roll no: 07, MSc part 1

2. Content
 What is Petroleum
 Petroleum product
 Analysis technique
 Instruments for analysis
 References

3. Petroleum
• Petroleum (also called crude oil) is a naturally mixture of hydrocarbons, generally in the liquid
state, that may also include compounds of sulfur, nitrogen, oxygen, and metals and other elements.
Inorganic sediment and water may also be present.
Composition
• The four fractional types into which petroleum is subdivided are paraffins, olefins, naphthenes, and
aromatics (PONA).
• Paraffinic hydrocarbons include both normal and branched alkanes
• Olefins refer to normal and branched alkenes that contain one or more double or triple carbon-
carbon bonds.
• Naphthene is a term specific to the petroleum industry that refers to the saturated cyclic
hydrocarbons (cycloalkanes).
• Aromatics includes all hydrocarbons containing one or more rings of the benzenoid structure.

4. Petroleum Products

5. Naphtha
• Boils from about 30°C (86°F) to approximately 200°C (392°F).
• The term petroleum solvent is often used synonymously with naphtha.
• Applications: Used by paint, printing ink and polish manufacturers and in the rubber and adhesive
industries as well as in the preparation of edible oils, perfumes, glues, and fats.
• Odor and Color: pale yellow in color, naphtha is usually colorless (water white).

6. Gasoline
• Gasoline (also referred to as motor gasoline, petrol in Britain, benzine in Europe)
• Used as fuel for internal combustion engines such as occur in motor vehicles, excluding aircraft.
• The boiling range of motor gasoline falls between –1°C (30°F) and 216°C
• (421°F) Gasoline boils at about the same range as naphtha (a precursor to gasoline) but below kerosene
Kerosene
•Kerosene (kerosine), also called paraffin or paraffin oil, is a flammable pale
yellow or colorless oily liquid with a characteristic odor intermediate in
volatility between gasoline and gas/diesel oil that distills between 125°C
(257°F) and 260°C (500°F)

7. Aviation fuel
• The term aviation fuel, as used in this text, is a collective term that includes aviation gasoline and
aviation gas turbine fuel as well as various types of jet fuel
The two basic types of jet fuels in general use are based on kerosene (kerosene-type jet fuel) and
gasoline (naphtha) (gasoline-type jet fuel).
Kerosene-type jet fuel is used in gas turbine engines.
Gasoline-type jet fuel are required for use in high-performance military aircraft.
• Aviation gasoline has a distillation range usually within the limits of 30°C(86°F) and 180°C (356°F).
• Gasoline type jet fuel distills between 100°C (212°F) and 250°C (482°F).
• API gravity, degrees = [141.5/(specific gravity 60°/60°F)] - 131.5
• Aviation fuel might be expected to have an API gravity in the range of 57 to 35 (specific gravity: 0.75
to 0.85, respectively).
• Freezing Point : The freezing point of the fuel (typically in the range –40 to –65°C, –40 to –85°F)

8. Lubricating oil
• Lubricating oil is used to reduce friction and wear between bearing metallic surfaces that are
moving with respect to each other by separating the metallic surfaces with a film of the oil. Lubricating
oil is distinguished from other fractions of crude oil by a high (>400°C/>750°F) boiling point.
Lubricating oils were at first by-products of paraffin wax manufacture
Grease
• Grease varies in texture from soft to hard and in color from light amber to dark brown. The largest
volume of grease in use is made from petroleum products produced from naphthenic, paraffinic,
blended, hydrocracked, hydrogenated, and solvent-refined stocks. In addition to petroleum oils, other
lubricating fluids, such as esters, diesters, silicones, polyethers, and synthetic hydrocarbons, are also
used.
WAX
• Paraffin waxes consist mainly of straight-chain alkanes (also called normal alkanes), with small
amounts (3–15%) of branched-chain alkanes (or isoalkanes), cycloalkanes, and aromatics.
• Color: Paraffin wax is generally white in color, whereas microcrystalline wax and petrolatum range
from white to almost black.

9. Density (Specific Gravity)
• (1) Density is the mass of liquid per unit volume at 15°C;
• (2) Relative density is the ratio of the mass of a given volume of liquid at 15°C to the mass of an equal volume of
pure water at the same temperature;
• (3) Specific gravity is the same as the relative density and the terms are used interchangeably.
• Usually a hydrometer, pycnometer, or more modern digital density meter is used for the determination of
density or specific gravity.
• API gravity, which is derived from the specific gravity:
• API gravity (degrees) = (141.5/sp gr 60/60°F) – 131.5
• It is also a critical measure for reflecting the quality of petroleum.
• API gravity or density or relative density can be determined using one of two hydrometer methods. The use of a
digital analyzer is finding increasing popularity for the measurement of density and specific gravity.
Distillation
• In the preliminary assay of petroleum the method of distillation is often used to give a rough indication of the
boiling range of the crude.

10. • Light Hydrocarbons
• Metallic Constituents
Multi element methods of determination using techniques such as atomic absorption spectrometry,
inductively coupled plasma atomic emission spectrometry, energy-dispersive Xray fluorescence
spectroscopy.
Viscosity and Pour Point
• Viscosity is usually determined at different temperatures (e.g., 25°C/77°F, and 100°C/212°F) by
measuring the time for a volume of liquid to flow under gravity through a calibrated glass capillary
viscometer
• The pour point of petroleum is an index of the lowest temperature at which the crude oil will flow
under specified conditions.
• In the original (and still widely used) test for pour point, a sample is cooled at a specified rate and
examined at intervals of 3°C (5.4°F) for flow characteristics. The lowest temperature at which the
movement of the oil is observed is recorded as the pour point.
Flash Point: The flash point is the lowest temperature at atmospheric pressure (760 mmHg, 101.3 kPa) at
which application of a test flame will cause the vapor of a sample to ignite under specified test conditions.

11. Analytical Instruments
• Ultraviolet absorption spectroscopy,
• Infrared spectroscopy,
• Mass spectrometry,
• Emission spectroscopy,
• Nuclear magnetic resonance spectroscopy continue to make major
contributions to petroleum analysis.

12. GC-MS Chromatography

13. What is chromatography

14. What is Gas Chromatography
• Performed in the vapour state
• Requires a mobile phase, gas
• Requires a stationary phase
• Molecules migrate between the phases

15. GC Instrument

16. Parts of GC-MS chromatography
• Carrier Gas, N2 or He, 1-2 mL/min
• Injector
• Oven
• Column
• Detector

17. Injector
Requirements for the ideal injector
• Capable to quantitative accept a broad
volatility range of sample components
• Extremely inert
• Able to handle polar/active compounds
• Provide optimum band shape

18. GC Instrument : column oven
• It is of metal tube
• Packed with silica
• Commonly obtained
pre-packed by vendors
• It allows the various
substances to partition
themselves

19. Separation
• Separation is based on the vapor pressure and polarity of the
components.
• Within a homologous series (alkanes, alcohol, olefins, fatty acids)
retention time increases with chain length (or molecular weight)
• Polar columns retain polar compounds to a greater extent than non-
polar
• C18 saturated vs. C18 saturated methyl ester

20. Detector
Detector Used for
1. Flame Ionization Detector (FID) -Compounds
containing Carbon
2. Thermal Conductivity Detector (TCD) -Universal
detection for gases without Carbon
3. Nitrogen Phosphorous Detector (NPD) -Selective
detection of Nitrogen and Phosphor containing
compounds
4. Electron Capture Detector (ECD) Selective -
detection of halogen containing compounds
5. Atomic Emission Detector (AED) -Selective
detection of elemental composition
6. Flame Photometric Detector- (FPD)

21. Detector
RESPONSE MECHANISM
• Concentration dependent: TCD, ECD, PID
• Mass rate dependent: FID, NPD, FPD
NON DESTRUCTIVE
• TCD, ECD, PID
DESTRUCTIVE
• FID, NPD, FPD
RESPONSE TYPE
• Universal: TCD, FID, PID
• Selective: ECD, NPD, FPD

22. Coupling Chromatography to Mass Spectrometry
Separation plus identification
Mass spectroscopy
Compounds enter the ion source and are
ionized and fragmented by using a high
energy electron bombardment. The ions are
extracted from the source with an electric
field and fed into the mass analyzer.
By applying electric fields, ions with a
certain mass to charge ratio can reach the
electron multiplier. The fragmentation pattern
measured is characteristic for each molecule,
making identification possible

23. • Mass spectrum depicting the
characteristic fragmentation
pattern of ethyl acetate (C4H8O2)
with at Mw=88.05 g/mol the
molecular (non-fragmented) ion.

24. • Limitations:
• Only compounds with vapor pressures exceeding about 10–10 torr can be analyzed by gas
chromatography mass spectrometry (GC-MS).
• Many compounds with lower pressures can be analyzed if they are chemically derivatized (for
example, as trimethylsilyl ethers). Determining positional substitution on aromatic rings is often
difficult.
• Certain isomeric compounds cannot be distinguished by mass spectrometry (for example,
naphthalene versus azulene), but they can often be separated chromatographically.
Accuracy
• Qualitative accuracy is restricted by the general limitations cited above. Quantitative accuracy is
controlled by the overall analytical method calibration. Using isotopic internal standards, accuracy
of ±20% relative standard deviation is typical.
• Sensitivity and Detection Limits
• Depending on the dilution factor and ionization method, an extract with 0.1 to 100 ng of each
component may be needed in order to inject a sufficient amount.

25. Analysis Time
In addition to sample preparation time, the instrumental analysis time usually is fixed by the
duration of the gas chromatographic run, typically between 20 and 100 min. Data analysis can take
another 1 to 20 hr (or more) depending on the level of detail necessary.
Complementary or Related Techniques
• Infrared (IR) spectrometry can provide information on aromatic positional isomers that is not
available with GC-MS; however, IR is usually 2 to 4 orders of magnitude less sensitive.
• Nuclear magnetic resonance (NMR) spectrometry can provide detailed information on the exact
molecular conformation; however, NMR is usually 2 to 4 orders of magnitude less sensitive

26. Applications
• Quantitation of pollutants in drinking and wastewater
• Quantitation of drugs and their metabolites in blood and urine for both pharmacological and
forensic applications
• Identification of unknown organic compounds in hazardous waste dumps
• Identification of reaction products by synthetic organic chemists
• Analysis of industrial products for quality control

27. References
• James G. Speight, “Handbook of Petroleum Product Analysis”, Published by John
Wiley & Sons, Inc., 2002
• Ronald A. Hites, “Gas Chromatography Mass Spectrometry”, Indiana University
School of Public and Environmental Affairs and Department of Chemistry
• Jana Hajšlová, Tomášjka, “Gas chromatography–mass spectrometry (GC–MS)”,
Institute of Chemical Technology, Faculty of Food and Biochemical Technology,
Department of Food Chemistry and Analysis