502 / | HD | CATALYST, SOLID SORBENT, OR SUPPORT THEREFOR: PRODUCT OR PROCESS OF MAKING |
400 | DF | SOLID SORBENT {6} |
416 | DF | .~ Free carbon containing {3} |
418 | DF | .~.~ Process utilizing solid or liquid source carbonizable material, or product thereof {9} |
430 | DF | .~.~.~ Treating with gas {2} |
432 | DF | .~.~.~.~ Specified atmosphere {2} |
435 | .~.~.~.~.~ Exposure to hot flue or exhaust gas |