Reduced puffing needle coke from coal tar distillate
View Patent ↗A reduced puffing needle coke is formed, which includes a reduced nitrogen content within the coke so that the coke particles do not experience as much puffing during the formation of graphitized carbon articles produced from such coke upon heating to graphitization temperatures.
1. A method of creating reduced puffing needle coke, comprising:
a. selecting coal tar distillate;
b. passing the coal tar distillate through an activated carbon nitrogen removal system to remove nitrogen from the coal tar distillate by adsorption and to produce reduced nitrogen coal tar distillate;
c. coking the reduced nitrogen coal tar distillate
d. calcining the coke obtained from step (c) to create calcined reduced puffing needle coke.
2. The method of claim 1 wherein the coal tar distillate of step a) has a nitrogen content of from about 0.5% by weight to about 2% by weight.
3. The method of claim 1 wherein the activated carbon nitrogen removal system of step b) 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 vessel type reactor.
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 b) 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 stripping regeneration at a temperature of at least about 100° C.
14. The method of claim 1 wherein the calcined reduced puffing needle coke of step d) has a nitrogen content of less than about 0.4%.
15. The method of claim 1 wherein the calcined reduced puffing needle coke of step d) has a nitrogen content of less than about 0.2%.
16. A method of creating reduced puffing needle coke, comprising:
a. selecting coal tar distillate;
b. passing the coal tar distillate through an adsorption zone to produce reduced nitrogen coal tar distillate;
c. coking the reduced nitrogen coal tar distillate;
d. calcining the coke obtained from step (c) to create calcined reduced puffing needle coke.
17. The method of claim 16 wherein the adsorption zone of step b) includes an inorganic adsorbent.
18. The method of claim 17 wherein the adsorbent is selected from the group consisting of alumina, silica gel, charged silica, silica alumina, titania, zirconia, zeolite, nickel oxide, copper oxide, iron oxide and combinations thereof.
19. The method of claim 17 wherein the adsorbent is activated alumina.
20. The method of claim 17 wherein the adsorption system further comprises a regeneration unit.
21. The method of claim 20 wherein the regeneration unit includes steam stripping of the contaminants from the adsorbent.
22. The method of claim 20 wherein the regeneration unit includes thermal stripping of the contaminants from the adsorbent.
23. The method of claim 16 wherein the calcined reduced puffing needle coke of step (d) has a nitrogen content of less than about 0.2%.