Preparation for the determination of carbon residues in petroleum products.
1. Install the instrument: install the electric heating furnace and temperature measurement control system of the instrument according to the instrument manual.
Whole. Among them, the thermocouple should be corrected, and the cold end should be led out with the corresponding compensation wire, and then the ordinary wire should be used.
Connect the cold junction and the temperature control instrument. The cold end should be inserted into the glass tube containing the transformer oil and put in.
In a thermos flask filled with ice water to ensure that the cold end is kept at 0°C; Thermocouples are used for temperature measurement and control.
Check the results and make corrections to ensure accurate measurement and control of the furnace temperature.
2. After calcining the clean porcelain crucible in a high-temperature furnace of 800C soil and 20C for 1h, take it out and empty it first.
Place in gas for 1 2min and then move into a dryer.
Cool in a dryer for about 40min, then weigh out the mass of the porcelain crucible to an accuracy of 00002g。
The new porcelain crucible should be calcined in a high-temperature furnace for no less than 2 hours, cooled in a dryer for about 40min, and then weighed to an accuracy of 00002g。Then re-put it in the high-temperature furnace for 1h and carry out the accurate weighing as above;
Calcination, cooling and weighing are repeated until the difference between continuous weighing is not greater than 00004g.
3. The sample in the bottle should not exceed three-quarters of the volume of the bottle. Shake the sample well for 5min. Viscous and contained.
Wax petroleum products should be pre-heated to 50°C and 60°C before shaking.
4. For water content greater than 05% of petroleum products are dehydrated prior to the determination of carbon residues.
5. For diesel 10% residue, the sample should be carried out no less than twice according to GB T255 or GB T6536.
of distillation. The 10% residue of the sample was collected for the determination of the carbon residue of the 10% residue of diesel fuel.
6. Before measuring the carbon residue, turn on the power supply to make the furnace temperature reach the specified range of 520 °C and 20 °C. Make use of electronics.
An automatic temperature controller controls the furnace temperature.