Study of the alteration of soil chemical attributes by the application of biochar from coffee straw (Coffea canephora): a Problematized Experimental Activity
Name: AMANDA MARSOLI AZEVEDO FEU
Publication date: 06/03/2025
Examining board:
Name |
Role |
|---|---|
| ANDRÉ LUÍS SILVA DA SILVA | Examinador Externo |
| GEISAMANDA PEDRINI BRANDAO ATHAYDE | Examinador Interno |
| PAULO ROGERIO GARCEZ DE MOURA | Presidente |
| PRISCILLA PAIVA LUZ | Coorientador |
Summary: The study evaluated the applicability of Problematized Experimental Activity (PEA) in higher education in chemistry, by investigating changes in the chemical attributes of a soil treated with coffee straw biochar. The research adopted a mixed approach, combining qualitative and quantitative methods, with an experimental design for biochar analysis and didactic intervention to evaluate learning. The biochars produced at different pyrolysis temperatures were characterized, analyzing their elemental compositions, thermal stability and impacts on the soil. The results showed that the pyrolysis temperature directly influences the chemical and structural properties of biochars, affecting their ability to improve soil fertility. The biochar produced at 600 °C (BC600) presented greater chemical stability and alkalinity, significantly reducing soil acidity and increasing the availability of essential macronutrients. In contrast, biochar produced at 350 °C (BC350) maintained a greater quantity of polar functional groups, favoring water retention and interaction with soil cations. The application of biochar demonstrated a dose-dependent effect on increasing soil pH and reducing the toxicity of exchangeable aluminum. In the educational context, the AEP facilitated the integration of chemical concepts and laboratory practices, promoting meaningful learning and the development of metacognitive skills. The analysis of the participants' feedback indicated that the experimental approach enhanced the understanding of chemical phenomena and reinforced the scientific contextualization of the contents. It is concluded that the use of biochar as a teaching tool and its application in soil represent a sustainable alternative for improving soil fertility and an effective pedagogical resource for teaching chemistry.
