Aplicação de planejamento fatorial a protocolo de extração e fixação de sulfetos volatilizáveis por acidificação (SVA) em amostras de sedimento Factorial design used on the extraction and fixation of acid volatile sulfides (AVS) from sediment samples

Abstract

The AVS is defined operationally as acid volatile sulfide, which is a controlling phase on the partition of some metallic species in sediments. A Factorial design was evaluated by means of 16 experiments and using four variables: temperature, extraction time, N2 flow, and volume of the S2- collection solution. The factors that contributed to the efficiency of the process were the extraction time and the N2 flow. Trapping of S2- was efficient in AAB. The S2- was quantified using a potentiometric procedure. Recovery tests for S2- concentrations varying from 1×10-5 to 1×10-4 mol L-1 were in the range from 93 to 116%.

Keywords

• factorial design
• sediments
• AVS