| 502 / | HD | CATALYST, SOLID SORBENT, OR SUPPORT THEREFOR: PRODUCT OR PROCESS OF MAKING |
| 100 | DF | CATALYST OR PRECURSOR THEREFOR {12} |
| 150 | DF | .~ Organic compound containing {13} |
| 162 | DF | .~.~ Organic phosphorus or nitrogen, except the ammonium ion {5} |
| 166 | | .~.~.~ Rhodium containing |