Recovery of silver residues from dental amalgam
J. appl. oral sci
; 18(2): 121-126, Mar.-Apr. 2010. ilus, tab
Artigo
em Inglês
| LILACS
| ID: lil-550403
Biblioteca responsável:
BR1.1
ABSTRACT
Dental amalgam residues are probably the most important chemical residues generated from clinical dental practice because of the presence of heavy metals among its constituents, mainly mercury and silver. OBJECTIVE:
The purpose of this study was to develop an alternative method for the recovery of silver residues from dental amalgam. MATERIAL ANDMETHODS:
The residue generated after vacuum distillation of dental amalgam for the separation of mercury was initially diluted with 32.5 percent HNO3, followed by precipitation with 20 percent NaCl. Sequentially, under constant heating and agitation with NaOH and sucrose, the sample was reduced to metallic silver. However, the processing time was too long, which turned this procedure not viable. In another sequence of experiments, the dilution was accomplished with concentrated HNO3 at 90ºC, followed by precipitation with 20 percent NaCl. After washing, the pellet was diluted with concentrated NH4OH, water and more NaCl in order to facilitate the reaction with the reducer.RESULTS:
Ascorbic acid was efficiently used as reducer, allowing a fast reduction, thus making the procedure viable.CONCLUSIONS:
The proposed methodology is of easy application and does not require sophisticated equipment or expensive reagents.
Texto completo:
Disponível
Coleções:
Bases de dados internacionais
Contexto em Saúde:
ODS3 - Saúde e Bem-Estar
Problema de saúde:
Meta 3.9: Reduzir o número de mortes por produtos químicos perigosos e contaminação do ar e água do solo
Base de dados:
LILACS
Assunto principal:
Prata
/
Resíduos Odontológicos
/
Amálgama Dentário
/
Recuperação e Remediação Ambiental
Idioma:
Inglês
Revista:
J. appl. oral sci
Assunto da revista:
Odontologia
Ano de publicação:
2010
Tipo de documento:
Artigo
/
Documento de projeto
País de afiliação:
Brasil
Instituição/País de afiliação:
State University of São Paulo/BR
/
University of São Paulo/BR