CPC Subgroup
C01B 21/40 Preparation by absorption of oxides of nitrogen
Full Title
Nitrogen; Compounds thereof > Nitrogen oxides; Oxyacids of nitrogen; Salts thereof > Nitric acid > Preparation by absorption of oxides of nitrogen
C01B 21/40 Nitrogen; Compounds thereof > Nitrogen oxides; Oxyacids of nitrogen; Salts thereof > Nitric acid > Preparation by absorption of oxides of nitrogen