Resumo

BRESSANI, Flavia A. et al. Focused-microwave-assisted digestion of encapsulated lubricating oils: gradual sample addition to pre-heated acid. Quím. Nova [online]. 2006, vol.29, n.6, pp. 1210-1214. ISSN 0100-4042.  http://dx.doi.org/10.1590/S0100-40422006000600012.

The applicability of the recently proposed procedure based on gradual sample addition to microwave-assisted pre-heated concentrated acid is limited by the sample viscosity. In this work, lubricating oil samples with high viscosity were encapsulated and manually added to the microwave-assisted pre-heated concentrated digestion mixture. The procedure was applied for determination of Al, Ca, Cr, Cu, Fe, Mg, Ni, P, Pb, Si, Sn, Sr, V, W, and Zn in lubricating oil by inductively coupled plasma optical emission spectrometry (ICP OES). Determined and certified values for Ca, Mg, P, and Zn in lubricating oil were in agreement at a 95% confidence level.

Palavras-chave : encapsulated lubricating oil; sample addition; focused-microwave.