Reduced puffing needle coke from decant oil
View Patent ↗A reduced puffing needle coke is formed from decant oil, which includes a lesser amount of nitrogen within the coke so that carbon articles produced from such coke experience minimal expansion upon heating to graphitization temperatures.
1. A method of creating reduced puffing needle coke, comprising:
a. passing decant oil through an activated carbon nitrogen removal system to remove nitrogen from the decant oil by adsorption and to produce reduced nitrogen decant oil;
b. hydrodesulfurizing the reduced nitrogen decant oil to create low-sulfur, reduced nitrogen decant oil;
c. coking the low-sulfur, reduced nitrogen decant oil
d. calcining the coke obtained from step (c) to create reduced puffing needle coke.
2. The method of claim 1 wherein the decant oil of step a) has a nitrogen content of from about 0.3% by weight to about 2% by weight and a ash content of from about 0.1% by weight to about 0.4% by weight.
3. The method of claim 1 wherein the activated carbon nitrogen removal system of claim 1 includes activated carbon with a surface area of from about 200 m 2 /g to about 3000 m 2 /g.
4. The method of claim 3 wherein the activated carbon is in the form of activated carbon fibers.
5. The method of claim 3 wherein the activated carbon is acid-washed or partially neutralized.
6. The method of claim 3 wherein the activated carbon has surface functional groups.
7. The method of claim 6 wherein the activated carbon is impregnated.
8. The method of claim 3 wherein the activated carbon nitrogen removal system comprises one or more columns.
9. The method of claim 8 wherein the column is a fixed-bed type.
10. The method of claim 8 wherein the column is a moving-bed type.
11. The method of claim 1 wherein the activated carbon nitrogen removal system of step a) further comprises a regeneration unit.
12. The method of claim 11 wherein the regeneration unit utilizes thermal regeneration at a temperature of from about 400° C. to about 1000° C.
13. The method of claim 11 wherein the regeneration unit utilizes steam regeneration at a temperature of at least about 100° C.
14. The method of claim 1 wherein the reduced needle puffing coke of step d) has a nitrogen content of up to about 0.2%.
15. A method of creating reduced puffing needle coke, comprising:
a. removing ash from decant oil to create ash-reduced decant oil;
b. passing the ash-reduced decant oil through an adsorption zone to produce reduced nitrogen decant oil;
c. coking the reduced nitrogen decant oil
d. calcining the coke obtained from step (c) to create reduced puffing needle coke.
16. The method of claim 15 wherein the adsorption zone of step b) includes an inorganic adsorbent.
17. The method of claim 16 wherein the adsorbent is selected from the group consisting of activated alumina, amorphous alumina, silica alumina, titania, ziconia, zeolite, silica gel, charged silica, nickel oxide, copper oxide, iron oxide and combinations thereof.
18. The method of claim 16 wherein the adsorbent is activated alumina.
19. The method of claim 15 wherein the adsorption zone further comprises a regeneration unit.
20. The method of claim 19 wherein the regeneration unit includes steam stripping of the contaminants from an adsorbent included in the adsorption zone.
21. The method of claim 19 wherein the regeneration unit includes thermal stripping of the contaminants from an adsorbent included in the adsorption zone.
22. The method of claim 15 wherein the reduced puffing needle coke has a nitrogen content of up to about 0.2%.