Removal of Color and Polyphenols from Sugarcane Molasses Ethanol Vinasse by Hydrodynamic Cavitation

The hydrodynamic cavitation process using orifice plates was applied to remove color and polyphenols from sugarcane molasses ethanol vinasse, with a treatment time of 1 h. The raw vinasse was diluted with tap water in a volume ratio of 1:10 in an acidic medium (pH 2). A 2^k factorial analysis was carried out to evaluate the effect of the inlet pressure of 2 and 3.6 bar. The results indicate that the interaction between the inlet pressure and the number of orifices has a significant effect on the color and polyphenol removal efficiency. The plate with 9 orifices under the condition of an inlet pressure of 3.6 bar was more efficient, achieving a maximum color removal of 32.71% and polyphenol removal of 88.62% during a 20 min treatment, with a cavitation yield of 0.00365 mg J^-1. The requirement of a longer treatment time did not favor the removal efficiency of color and polyphenols. Hydrodynamic cavitation significantly improves the removal of color and polyphenols, being a viable alternative to reduce toxicity in alcoholic vinasse, contributing to environmental improvements for the alcohol industry.