Vermicompost as a natural adsorbent material: characterization and potentialities for cadmium adsorption

Autor(es)

Madson G. Pereira ^[1] ; Marco A. Z. Arruda ^[2]

Afiliação do(s) autor(es)

^[1] Universidade Estadual de Campinas. Instituto de Química - Brasil

^[2] Universidade Estadual de Campinas. Instituto de Química - Brasil

• Tipo de documento: Artigo Científico
• Fonte: Journal of the Brazilian Chemical Society; v. 14, n. 1, p. 39-47, 2003-01-00.

Resumo

Vermicompost (humic material) samples were submitted to characterization by infrared spectroscopy, X-ray diffractometry, thermogravimetric analysis, electron microscopy etc. In addition, its cation exchange capacity (CEC) was determined. Factorial experiments were designed in order to elucidate the interaction mechanisms between Cd2+ and the adsorptive sites of vermicompost. The maximum adsorptive capacity for cadmium was evaluated by a Langmuir isotherm. The characterization revealed that vermicompost exhibits high CEC values (ca. 72.9 meq per 100 g), high surface area (porous material), chelating groups and a maximum adsorptive capacity for Cd (38.6 mg g-1) at pH 5.0. This potential application was exploited in the analysis of synthetic and real (mineral water) samples with Cd concentrations of ca 5 mug L-1, requiring a preconcentration step. An enrichment factor of 100 was attained. (AU)

• Processo FAPESP: 99/12124-7 - Emprego de novos materiais e diferentes ambientes reacionais para melhoria em sensibilidade e seletividade na análise de amostras biológicas e ambientais
• Beneficiário: Elias Ayres Guidetti Zagatto
• Modalidade de apoio: Auxílio à Pesquisa - Temático