Study of the interactions of copper (II) with humic-like substances extracted from hydrochar from sugarcane bagasse and vinasse

Abstract

Humic substances (HS) are complex macromolecular components resulting from the chemical and biological degradation of plant and animal waste, which have diverse structures and functionalities. They are widely distributed in soils, water bodies and sediments. Studies have shown that hydrothermal carbonization (HTC) of biomass produces a carbon-rich material called hydrochar and a liquid phase called process water. The procedure employs mild temperatures of a maximum of 300 ° C, wet biomass and self-generated pressures. The hydrochar may have, in its structure, high amount of organic matter and some nutrients. This paper aims to characterize and study the behavior of interactions of "humic-like substances" (HLS) extracted from hydro char with copper (II) metal. In this work, HTC will be conducted using the by-products of the sugar-energy sector, sugarcane bagasse and vinasse. The HTC will be carried out at 232 °C using a mixture of sugarcane bagasse and vinasse with the addition of 2.5% (v/v) potassium hydroxide to the reaction. HLS will be extracted from hydro char following the recommendations of the International Humic Substances Society (IHSS).HLS extracted from hydro char will be characterized by infrared (FTIR), elemental analysis (CHNS), UV-Vis spectrophotometry, Molecular Fluorescence, Carbon Nuclear Magnetic Resonance (13C NMR) and two-dimensional correlation spectroscopy (2D-FTIR-COS). (AU)