Study of the use of food waste as bioadsorbents to remove methylene blue dye

ABSTRACT

The disposal of untreated effluents and the lack of efficient and effective treatment have raised concerns. In this sense, methylene blue dye is classified as a priority contaminant among the dyes released into industrial effluents. It is used in several segments, such as dyeing cotton, silk, paper, paints, among others. In this context, the use of bioadsorbents obtained from food waste to remove methylene blue dye would be a viable alternative, as it allows the use of waste generated in large quantities and at low cost, in addition to being an environmentally friendly alternative. Totally correct and sustainable. Therefore, the main objective of this work was to study the use of food waste as bioadsorbents in the removal of methylene blue dye. To achieve this, bio-adsorbents were produced from food waste, such as chicken eggshells, passion fruit peels and orange peels, in natura, thermally activated and chemically activated. The characterization of the bioadsorbents produced was carried out through analyzes of specific surface area, thermal behavior, morphology and structure, in addition to determining yield. The performance of the bioadsorbents was comparatively evaluated in the batch adsorption process to remove the methylene blue dye. The adsorption tests showed that the bioadsorbents developed were efficient in removing the dye, showing removal of more than 64%. The samples that obtained the best results were passion fruit peel, with thermal (MT) and chemical (MQ) treatment, and orange, with chemical treatment (LQ), achieving dye removals greater than 98%, due to their high specific surface areas. It was not possible to obtain adsorption isotherms for samples MQ and LQ, due to the high percentages of dye removal achieved, even for the different initial concentrations studied.

Keywords:
Methylene Blue; Food Waste; Bioadsorber