Estudo físico-químico da fotodegradação de corantes alimentícios

Abstract

The food industry employs an enormous amount of dyes in their processes. Which cause the color of the effluent, being able to be highly interfering in the photosynthetic procedures. It is stimated that more than 700,000 tons of 10,000 different types of dyes are produced by industries. Food colors are substances that impart, intensify or restore the color of a particular product. Research has recently shown that approximately 12% of synthetic dyes are lost in the production and use processes, reaching the environment, and their pigmentation can eliminate the photosynthetic processes in water courses. In addition to the environmental problem related to color, many of the primary degradation products of these effluents can be toxic and / or non-biodegradable. In the present work a physicochemical study of photodegradation of food colors, kinetic study of dye photodegradation and pH variations under adverse conditions was carried out in the absence of photocatalysts. The quantification of dyes in solutions, before and after photodegradation, was performed using UV / Vis spectroscopy. The results show a significant reduction of the characteristic bands of the dye, in relatively short time intervals. It was observable that the higher the concentration and the lower the pH, the lower the discoloration kinetics.