Kinetics of Heterogeneous Reduction of Red-Brown Zh Vat Dye with Rongalite in the Absence of Diffusion Hindrance

The kinetics of heterogeneous reduction of red-brown Zh vat dye with formaldehyde sodium sulfoxylate (rongalite) was studied. The dye was reduced in the form of nonporous disk, which eliminates the effect of mass transfer on the reaction rate. The stages of the reduction mechanism and the reaction rate equations are proposed.