502 / | HD | CATALYST, SOLID SORBENT, OR SUPPORT THEREFOR: PRODUCT OR PROCESS OF MAKING |
100 | DF | CATALYST OR PRECURSOR THEREFOR {12} |
300 | DF | .~ Metal, metal oxide or metal hydroxide {10} |
349 | .~.~ Of Group IV (i.e., Ti, Zr, Hf, Ge, Sn or Pb) {2} | |
350 | DF | .~.~.~> Of titanium {1} |
352 | DF | .~.~.~> Of tin |