Preparation and Characterization of Carbon From the Fruit of Brazil Nut Tree Activated by Physical Process

Abstract

Activated carbon is the name of a big group of materials that presents high degree of porosity and, consequently, an extended internal surface area, with physical and chemical adsorption properties. Innumerous raw materials can be used as precursors, especially biomass. The objective of this study was to obtain activated carbon from physical activation of the fruit of Brazil nut tree (“ouriço”) and to evaluate its physical and chemical properties in function of the differences between the temperatures and atmospheres of activation. The samples were carbonized at 3 different temperatures and the carbons were activated under atmosphere saturated by CO2 or steam. The results showed the influence of activation temperature and atmosphere on physicochemical characteristics of carbon. The carbon from woody Brazil nut seed capsule activated by CO2 and steam at different temperatures had a microporous profile, indicating its use to adsorb organic molecules of small dimensions. Basic characteristic was observed on samples and the carbon produced was thermally stable. Best quality was attributed to carbon activated by steam at 800 °C.

Preparation and characterization of steam and CO2 activated carbon from Brazil nut shell

“…Fourier transform infrared spectroscopy (FTIR) from 4000 to 400 cm -1 (Perking Elmer Spectrum BX FT-IR System) was performed to identify the functional groups present in the sample (Rimoli et al 2019).…”

“…Different activation methods can be applied to the production of activated carbon, with emphasis on physical and chemical methods. Chemical activation is currently the most explored by scientists, but its high cost compared to physical methods, besides the need for an additional washing step, means that its application on commercial scale is unfavorable (Rimoli et al 2019).…”

Carvão ativado oriundo do mesocarpo do fruto da castanha de caju (Anacardium ccidentale) na remoção de corante em meio aquoso

“…Quanto aos tipos de ativação, podem ser definidos como elementos responsáveis pelo processo de elevação da área superficial do material, através de reações ocorrentes no mesmo, com métodos químicos e físicos. Dessa maneira, a ativação física consiste na carbonização por meio de pirólise: neste processo ocorre a remoção de materiais que não contém carbono, seguido de exposição a temperaturas que variam de 800 °C a 1000 °C (Rimoli, et al, 2019).…”

Adsorção do corante básico Verde Malaquita via carvão ativado a partir do caroço de açaí

“…A ativação física consiste na carbonização por meio de pirólise com uso de CO2 ou vapor de água, neste processo ocorre a remoção de materiais que não contêm carbono, seguido de exposição a temperaturas que variam de 800°C a 1000°C (Rimoli et al, 2019). Já na ativação química, uma matéria-prima é impregnada com um elemento ativador como H3PO4, ZnCl2, NaOH, KOH, entre outros, e o material impregnado é aquecido em atmosfera inerte.…”