Optimizing treatment of alcohol vinasse using a combination of advanced oxidation with porous α-Fe2O3 nanoparticles and coagulation-flocculation

This study utilizes a novel method, namely the combination of advanced oxidation processes with synthesized highly porous alpha-Fe2O3 nanoparticles and coagulation-flocculation with polyacrylamide, to investigate the effects on COD removal in alcohol vinasse. Highly porous alpha-Fe2O3 nanoparticles were prepared via a chemical precipitation technique. The characteristic of the synthesized alpha-Fe2O3 nanoparticles were determined by FT-IR, Raman spectroscopy, XRD, SEM, and N-2 adsorption-desorption isotherms. The effect of different alpha-Fe2O3 nanoparticles loading for chemical oxygen demand (COD) removal efficiency was investigated. The results revealed that at alpha-Fe(2)O3 nanoparticle dose of 3000 ppm had the highest COD removal for vinasse. Then, central composite design (CCD) was used to optimize the operating variables such as pH, time, oxidant dosage, and coagulant dosage, and their optimum values were determined to be pH:7.36, 90 min, 17.89 wt% oxidant dosage, and 1.6 wt% coagulant dosage, to achieve a high COD removal efficiency in 70 celcius for alcohol vinasse (98.64%). Based on optimal conditions, the porous alpha-Fe2O3 nanoparticles possess superior catalytic activity in the advanced oxidation process compared to other treating methods. Also, the mechanism of the catalytic oxidation reaction is evaluated.

Automated summary

This study investigates the effects of a novel method combining advanced oxidation processes with highly porous alpha-Fe2O3 nanoparticles and coagulation-flocculation with polyacrylamide on the removal of COD in alcohol vinasse. The results show that this method can achieve efficient COD removal under specific conditions.