EXAMPLE #2(Contd. ◆ Maleic anhydride from benzene E> High selectivity at almost complete conversion-no recycle required e Benzene is expensive and is a carcinogen o Maleic anhydride from Butane E Lower selectivity-cannot operate at complete conversion e Butane is relatively cheap almost all new plants use butane as the feedstock. 1l/19/99 Input-Output Structure11/19/99 Input-Output Structure 7 EXAMPLE #2 (Cont’d.) u Maleic Anhydride from Benzene ð High selectivity at almost complete conversion - no recycle required ð Benzene is expensive and is a carcinogen u Maleic Anhydride from Butane ð Lower selectivity - cannot operate at complete conversion ð Butane is relatively cheap Almost all new plants use butane as the feedstock