Development of hydrochar and magnetic char for carbon sequestration, nutrients release and environmental pollutants remove

• Grant number: 24/17456-1
• Support Opportunities: Regular Research Grants
• Start date: July 01, 2025
• End date: June 30, 2028
• Field of knowledge: Physical Sciences and Mathematics - Chemistry
• Principal Investigator: Márcia Cristina Bisinoti
• Grantee: Márcia Cristina Bisinoti
• Host Institution: Instituto de Biociências, Letras e Ciências Exatas (IBILCE). Universidade Estadual Paulista (UNESP). Campus de São José do Rio Preto. São José do Rio Preto , SP, Brazil
• Associated researchers: Altair Benedito Moreira

Abstract

Great challenges of global Sustainable Development involve climate change, the remediation of contaminated areas and sustainable agriculture. Hydrothermal (CH) and magnetic (CM) charcoal can be produced from the Hydrothermal Carbonization (HTC) of sugarcane bagasse and it be used for agricultural purposes and to remove metals . This material has not yet been tested for CO2 capture, the hypothesis of this work being that CH when applied to the soil could CO2 sequestation and release nutrients. In this work, the effect of time and temperature of the sugarcane bagasse CHT process using urea as an additive will be evaluated on the properties and functional groups of CH. Magnetic coals will also be produced by CHT from sugarcane bagasse in one step in the presence of iron salt.To increase the quantity and types of functional groups on the surface of CH and CM, thermochemical and/or thermophysical activation will be carried out, evaluating the effect of activation time, type of chemical additives such as urea and NaOH, as well as thermophysical activation conditions with CO2, varying the temperature between 500 and 900 oC. The characterization of the coals will be carried out by X-ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), XPS and carbon adsorption-desorption isotherms. N2. A batch study will also be carried out to evaluate the dose, equilibrium time (adsorption kinetics), N2 isotherm of the metals cadmium (II), nickel (II) and lead (II) by coals. It is also intended to conduct incubation tests in microcosms with samples of weathered soils (argisol) already available in the laboratory.The microcosms will be built in plastic bottles, to which soil contaminated with the target metals (Pb, Cd and Ni) and different rates of application of hydrothermal charcoal will be added. The microcosms will have, at times that will be experimentally defined, the concentrations of target metals in the soils determined, using the BCR sequential extraction method, to evaluate the metals in the exchangeable fractions, reducible oxides and the organic fraction. CO2 adsorption studies will be conducted using Micromeritics equipment under low pressure (0-1 bar) at different temperatures (25, 50 and 70 ºC). In this sense, the end of this project is expected to fill knowledge gaps in the area of ¿¿remediation of contaminated soils, release of nutrients and carbon sequestration by exploring the potential of carbonaceous materials derived from biomass to promote environmental recovery and contribute to the development of sustainable solutions and effective for contemporary environmental challenges. (AU)