Rapid oxidative dehairing using alkaline hydrogen peroxide and potassium cyanate: Reuse of the dehairing reagents

Studies have continued on rapid dehairing of cattlehide using an oxidative system of alkaline hydrogen peroxide and potassium cyanate. For economic viability, the dehairing Mixture needs to be used for more than one dehairing cycle. The number of cycles is dependent upon the residual concentration of the reagents in solution, namely, NaOH, H2O2 and KOCN. The concentrations of these reagents were measured after each dehairing cycle. In addition the solubilized protein concentration and the amount of insoluble material suspended in solution were determined. NaOH, H2O2 and KOCN all decreased with an increase in the number of dehairing cycles. After the 6th or 7th cycle the dehairing times had increased to the point where dehairing still occurred, but was no longer rapid. There was a buildup of soluble protein in solution as well as suspended (insoluble) material with increasing dehairing cycles. Both the protein and insoluble (mostly hair) material reacted with the dehairing chemicals, resulting in a decrease in the efficacy of the dehairing mixture. Nevertheless, the system appears to offer a viable alternative to sulfide-based rapid dehairing, and further experimentation on a pilot plant scale is merited.