Trace Asphaltenes Test (TAT) for Deasphalted Oil
Area
3
Job Hazards
Unit
Lab
Yes
Operating Procedure #
OPS-LB-NM-029
Job Hazards
Access and Egress
Moving Parts
Activities of Others
Noise
Adverse Weather
Rail Movement
Chemical Exposure
Sharp Edges
Electricity
Slips, Trips, and Falls
Fatigue
Static Electricity
Fire and Explosion
Trip Injuries
Ground Contamination
Trapped Pressure
Manual Handling
Working at Height
Certified by
Revision #
Date
09.20.2011
Scope / Objective
Yes
PPE
Standard (SSP-0011)
Page
1 of 1
Use
Y
Full Face Shield / Goggles
Hood
Clothing—Chemical Protection
Gloves—Chemical
Personal Fall Protection
References / Documents
Respirator / Filter Mask
Supplied Air
 MSDS on gasoline.
 Unit Safe Upper & Lower Limits Spreadsheet
Other:
Equipment
Materials and Reagents
Special Instructions
Environmental
Trace Asphaltenes Test (TAT) for Deasphalted Oil
1
Place a pad of filter paper in an oven at about 105°C for 15 minutes. Cool in a desiccator and weigh to the nearest 0.1 mg.
2
For samples with results greater than 250 ppm of asphaltenes, the sample is to be hot filtered in inert atmosphere with a #40
Whatman filter paper (or equivalent) prior to the analysis. This will remove any extraneous materials that are not dissolved
asphaltenes from the sample.
3
To the nearest 0.01 grams, weigh approximately 20 grams of DAO into the Erlenmeyer flask. Add 200 mls of n-Heptane and a
magnetic stir bar to the flask. Attach the flask to the Allihn condenser and place on hot plate, start the stirrer. Turn the heat on so
that the n-Heptane refluxes gently in the condenser.
4
Place the filter in the vacuum filtration apparatus and wet with 5 to 10 mls of n-heptane. When the DAO/n-heptane in the
Erlenmeyer has refluxed for 20 minutes, stop the heat and stirring. Remove the stir bar and let the flask stand 10 minutes.
5
Filter the DAO/n-heptane through the vacuum filtration apparatus. While the flask is still warm, carefully wash the flask with two 20
ml washes of fresh n-heptane and filter the washings. Wash the filter with n-heptane until the washings are clear (usally three 10 ml
washings are sufficient). It is very important that the filter be free of oil.
6
Place the filter in an oven at about 105°C for 15 minutes. Cool in a desiccator and weigh to the nearest 0.1 mg.
Calculations:
Calculate the amount of asphaltenes in the DAO as follows:
Ppm wt. asphaltenes = (A-A’)/B X 1,000,000
wt% = (A – A’)/B X 100
Where:
A is the filter weight after filtration.
A’ is the filter weight prior to filtration.
B is the weight of the sample.
Report results to the nearest 1 ppm.
Completed Date:
Note:
Prepared By:
Approved By:
This procedure is only valid at the time of printing. The control version can be found on the Meraux Refinery intranet.