Rashin gas din gas yana nufin aiwatar da cire nitrogen oxides daga gas din konewa don hana yawan nitrogen oxides daga gurɓata muhalli bayan konewar kwal a cikin tukunyar jirgi.
Hanyoyin fasaha na gas din gas din sune mafi yawan:
Taswira: Ta hanyar katalaishi, amoniya yana so daidaiwa don rayuwar gashen ayyuka a cikin hanyar 280-420℃ don samun rayuwanci da mai tsaye daga nitrogini ta tafiya nitrogini da ido.
● Ka'ida: Babu da katalaishi, rubutun samun da amoniya ko urea yana so daidaiwa don hanyar ayyuka a cikin kiyayyaki ga 850-1100℃ don samun rayuwanci da nitrogini.