is often interchangeably referred to as petroleum. This is

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M A - 3 S O L O A P P L I C A T I O N N O T E

ABOUT THE SAMPLE

Mercury is a hazardous heavy metal, unknown until the mid-50s where severe mercury poisoning causing neurological effects was discovered in Minamata Japan, later known as Minamata Disease. The cause of death was eventually identified as an industrial discharge that contains an extremely high level of mercury. Over 1,700 people of 2,200 victims, as well as many other animals such as fishes, cats, and dogs, died as a result. In addition to this tragedy, the victims also suffered from social and political issues before action and help were provided. In 2013, under the United Nations Environment Program, delegates from 128 countries gathered at Kumamoto to officially adopt and ratify the “Minamata Convention on Mercury”. The objective is to protect human health and the environment from anthropogenic emissions of mercury and its associated compounds. To know more, please visit: http://www.mercuryconvention.org/

ABOUTMERCURY &MINAMATA DISEASE

APPN-MA-3SOLO-PETRO-003

Crude oil is a naturally occurring liquid fuel source accumulated in geological formations beneath the Earth’s surface. It is a fossil fuel made up of a mixture of hydrocarbons - hydrogen and carbon atoms. Crude oil is often interchangeably referred to as petroleum. This is because petroleum includes both unrefined crude oil as well as refined petroleum products. Globally, crude oil is one of the most important fuel sources. Not only does it account for one-third of the contribution to the world’s energy needs on both transportation and electricity generation, but its refined products are also essential feedstocks to the petrochemical industries to produce polymers, plastics and more that are needed in our daily life.

Like crude oil, mercury is a naturally occurring element, but as a contaminant. Mercury levels in crude oil can vary widely, both between and within reservoirs and geographical areas. Concentrations vary from low ppb (parts per billion) to low ppm (parts per million). Mercury is universally detrimental to petroleum processing systems. It amalgamates with other metal materials in the process lines, which accumulates and causes potential galvanic corrosion and embrittlement (aluminium) of equipment, all possibly resulting in catastrophic situations. Maintenance workers in the petroleum industry can be at risk due to inhalation of mercury vapor and dermal absorption of organic mercury compounds unless proper precautions are implemented.

When the refinery process lines are contaminated with mercury, the mercury can remediate down to its refined products such as LPG, Naphtha, Gasoline, and Jet Fuel, which will impact the downstream petrochemical processing, consumer usage and environment. Therefore, it is crucial to control and regulate the mercury contents in petroleum processes.

This application demonstrates the easy, quick, efficient, accurate and reliable analytical technique and procedure to analyze for Total Mercury in Crude Oil.

MEASUREMENT OF TOTALMERCURY INCRUDE OILTechnique:Direct Thermal Decomposition - GoldAmalgamation - Cold Vapor AtomicAbsorption Spectroscopy (CVAAS)

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Principle of OperationA weighed sample in a boat is loaded into MA-3 Solo. As purified airflow begins, the Decomposition furnace temperature is increased in stages; first to dry the sample, then to decompose it. Evolved gases are carried through a heated catalyst to produce free mercury. Combusted products are swept through a Gold-Amalgamation trap where the mercury is concentrated. The trap is then heated to release the mercury into a carrier gas that transports it into an atomic absorption spectrometer’s measurement cell. The NIC MA-3 Solo works on

InstrumentationInstrument used in this experiment is the NIC MA-Series, MA-3 Solo. It employs Direct Thermal Decomposition - Gold Amalgamation - CVAAS technique to determine total mercury in various types of samples.

Introduction of Analytical MethodSeveral methods were established in the past to analyze Mercury in environmental samples. Most methods, like the ICP-MS and the conventional AAS, require a sample pretreatment process before the analysis. However, the sample pretreatment is not only time consuming, but also generates hazardous waste. EPA 7473 is one

Quick, Easy & Accurate Analysis of Mercury

No Hazardous Chemicals Involved

Low Operational CostTHE BENEFITS

OF THE DIRECT COMBUSTION

METHODFast Turnaround Time

of the established reference methods of Thermal Decomposition Mercury Analysis. Direct Thermal Decomposition, also commonly known as Direct Combustion, allows direct analysis of solid and liquid samples without wet chemical sample pretreatment.

the principle of Cold Vapor Atomic Absorption Spectroscopy, where monochromatic light at a wavelength of 253.7 nanometers is attenuated by mercury vapor in a measurement cell. According to the Beer-Lambert Law: Absorbance is equal to the molar absorptivity times the concentration times the path length. In simple terms, since epsilon and path length are constant, absorbance is proportional to concentration.

Furnace

Catalyst DecompositionHg amalgam(Furnace)

Purified air

SampleboatMeasurement

cell

MA-3 Solo can be used to handle solid, liquid,and gaseous sample with suitable accessories.

This system is compact with a small footprintthat requires no gas for its operation.

It is robust and equipped with a wide measurement range of 0 to 10,000 ng

Besides that, it is lightweight and equipped withadvanced optics for superior sensitivity and stability.

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Analysis Plan The crude oil samples used in this test were collected from the petroleum laboratories. The analysis was done in accordance with UOP 938-20 procedure. Charcoal pellets were added as an additive to absorb any volatiles and control combustion. The measurements are done in multiple replicates of each sample, periodically with Check Standard from

STD [ppm]

SVOL [µL]

STD [ng]

ABS VALUE

MEAS [ng]

DEV [%]

0.00 0.00 0.0 0.00165 0.000 -

0.01 50.00 0.5 0.05886 0.488 2.4

0.01 100.00 1.0 0.11632 0.979 2.1

0.10 50.00 5.0 0.59174 5.037 0.7

0.10 100.00 10.0 1.17596 10.025 0.2

0.10 200.00 20.0 2.34211 19.980 0.1

Table 1

Calibration

a secondary Standard solution. Secondary Check Standard is prepared from a certif ied Oil-Standard (CONOSTAN® 100ppm) serially diluted down to 1,000 µg/kg (ppb) and 98 µg/kg (ppb) respectively using CONOSTAN® recommended PremiSolv, to validate the precision and accuracy of the analyzer’s measurements.

Sample Preparation:

Transfer the sample boat to MA-3 Solo for analysis.

Fill sample boat with charcoal pellets to the amount as shown.

Due to crude oil viscosity, it is easier to introduce the sample by weight.

CALIBRATION

STD{NG}

AB

S{A

RE

A}

0.0

1.5

0 5 15

y=ax+Blanka= 1.17142E-01b= 1.64600E-03r= 1.0000

2.5

2.0

1.0

0.5

10 20

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Sample Result

NO SAMPLE SVOL [µL]

ABS VALUE

MEAS [ng]

CONC. [µg/kg]

RECOVERY [%]

1 R.Blank - 0.003101 0.012 - -

2 R.Blank - 0.003113 0.013 - -

3 Check STD (1.00ng) 100.00 0.119700 1.008 9.96 100.8

4 CONOSTAN® (98 µg/kg) 41.35 0.481091 4.093 98.68 -

5 CONOSTAN® (98 µg/kg) 41.35 0.473348 4.027 97.09 -

6 CONOSTAN® (1000 µg/kg) 16.74 1.917135 16.352 976.08 -

7 CONOSTAN® (1000 µg/kg) 16.74 1.995161 17.018 1015.86 -

8 CONOSTAN® (1000 µg/kg) 16.74 1.939682 16.544 987.54 -

9 Cruide Oil 2 101.74 0.020385 0.160 1.45 -

10 Cruide Oil 2 102.85 0.019485 0.152 1.36 -

11 Cruide Oil 2 113.12 0.021695 0.171 1.40 -

12 Check CONOSTAN® (98 µg/kg) 41.35 0.498378 4.240 102.24 104.3

13 Check STD (1.00ng) - 0.115558 0.972 - 97.2

14 Cruide Oil 4 108.89 0.435169 3.701 33.87 -

15 Cruide Oil 4 110.17 0.438385 3.728 33.73 -

16 Cruide Oil 4 103.18 0.414904 3.528 34.07 -


18 Check STD (10.00ng) - 1.199976 10.230 - 102.3

19 Cruide Oil 5 100.44 0.211771 1.794 17.74 -

20 Cruide Oil 5 106.93 0.227584 1.929 17.92 -

21 Cruide Oil 5 110.84 0.242363 2.055 18.43 -


23 Check STD (10.00ng) - 1.213881 10.348 - 103.5

Table 3

Operating Conditions

a. Heat method used : Solid/Heavy Oilb. Carrier gas : Airc. Combustion tube : Normald. Additive Used : Charcoal Pelletse. Method Compliance : UOP-938-20

Table 2

PARAMETERS TEMPERATURE (OC) TIME (SECONDS)

Atomize 1 0 0

Atomize 2 350 180

Atomize 3 850 360

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ConclusionNIC MA-3 Solo can analyze crude oils with good accuracy, repeatability, and reproducibility.

Discussions

Crude oil is a mixture of a comparatively complex combination of hydrocarbons consisting predominantly of aliphatic, alicyclic and aromatic hydrocarbons, though it also contains some nitrogen, sulfur, and oxygen. Its vapor pressure (boiling point) varies depending on the hydrocarbon compositions.

With such a wide range of volatility, it is highly crucial to ensure proper sample handling and transfer to measurement, keeping sample integrity to avoid any loss due to volatilization, which will affect the analytical results. The use of charcoal pellets as an additive offers the flexibility to effectively analyze all crude oil variety types (regardless of light or heavy) with minimal volatile loss. The absorption on charcoal pellets allows the crude oil to process through a controlled and complete combustion, avoiding any soot formation in the system that can affect both accuracy and precision measurements.

The thermal decomposition technique proves to be an efficient and accurate method to analyze mercury in liquid hydrocarbons. As compared to the conventional wet-chemistry cold-vapor technique, thermal decomposition does not require any use of wet reagents and wet-chemical preparation. Each analysis is easily completed in 9 to 10 minutes. Operating according to UOP 938-20 procedure, excellent precision is achieved on all crude oil samples. The consistent good recoveries on both CONOSTAN® secondary traceable solvent-based standard and regular aqueous Check STD confirm the analyzer’s performance.

Result Statistics

SAMPLE TRIAL Ave [µg/kg] S.D. [µg/kg] CV [%]

CONOSTAN® (98 µg/kg) 2 97.8850 1.124300 1.15

CONOSTAN® (1000 µg/kg) 3 993.1600 20.476826 2.06

Crude Oil 2 3 1.4033 0.045092 3.21

Crude Oil 4 3 33.8900 0.170880 0.50

Crude Oil 5 3 18.0300 0.357911 1.99

Table 4

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Nippon Instruments Corporation

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is often interchangeably referred to as petroleum. This is