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All publications of “Gelton Geraldo Fernandes Guimarães”

3 results

Value of Functionalized Charcoal for Increasing the Efficiency of Urea N Uptake: Insights into the Functionalization Process and the Physicochemical Characteristics of Charcoal

Diogo Mendes de Paiva ORCID logo , Gelton Geraldo Fernandes Guimarães ORCID logo , Breno Cardoso Teixeira ORCID logo , Reinaldo Bertola Cantarutti ORCID logo


ABSTRACT Functionalized charcoal (CHox) incorporated into urea is known for its ability to reduce NH3 volatilization and increase agronomic efficiency. However, it is important to optimize the functionalization process and to elucidate its relationship with the physicochemical properties of CHox for N supply. Thus, charcoal obtained from eucalyptus wood was functionalized with different HNO3 concentrations and reaction times. Ammonia adsorption by CHox was evaluated in chambers with high NH3 concentrations. Dry matter yield, N uptake, and apparent N recovery efficiency […]

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Functionalized Charcoal as a Buffering Matrix of Copper and Zinc Availability

Gelton Geraldo Fernandes Guimarães, Amanda Soares Giroto, Breno Cardoso Teixeira, Leonardus Vergütz, Reinaldo Bertola Cantarutti


ABSTRACT: High copper (Cu) and zinc (Zn) contents in soil can cause phytotoxicity to plants and contaminate surface and groundwater, with negative effects on agriculture and the environment. Functionalized charcoal (OCh) has high cation exchange capacity (CEC) and the ability to adsorb Cu and Zn and control their availability in the soil and water. An adsorption study at two pH levels was carried out to evaluate increasing Cu and Zn sorption capacity provided by the functionalization process of a charcoal. […]

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Urea coated with oxidized charcoal reduces ammonia volatilization

Diogo Mendes de Paiva, Reinaldo Bertola Cantarutti, Gelton Geraldo Fernandes Guimarães, Ivo Ribeiro da Silva


Urea is the most consumed nitrogen fertilizer in the world. However, its agronomic and economic efficiency is reduced by the volatilization of NH3, which can reach 78 % of the applied nitrogen. The coating of urea granules with acidic compounds obtained by charcoal oxidation has the potential to reduce the volatilization, due to the acidic character, the high buffering capacity and CEC. This work aimed to evaluate the effect of HNO3-oxidized carbon on the control of NH3 volatilization. These compounds […]