Multivariate optimization of the determination of zinc in diesel oil employing a novel extraction strategy based on emulsion breaking

Evaluation of Different Methods for Copper Determination in Insulating Oils by Graphite Furnace Atomic Absorption Spectrometry

“…Este resultado já era esperado, já que em outros trabalhos também foi observado que os extratos aquosos se comportam exatamente da mesma maneira que as soluções padrão aquosas, tanto no que diz respeito ao transporte quanto no que diz respeito ao comportamento térmico do analito durante o aquecimento. 6,7 Já para a metodologia em que as amostras foram introduzidas no espectrômetro na forma de emulsões, o método da curva analítica não pode ser aplicado. Neste caso, as inclinações das curvas analíticas construídas com emulsões preparadas a partir de um óleo mineral isolante novo (0,0036 L µg -1 em média), isento de cobre, apresentaram grandes diferenças em relação às curvas de adição do analito preparadas com as amostras, cujos valores de inclinação variaram de 0,0029 a 0,0067 L µg -1 .…”

“…5 Estes problemas são particularmente críticos quando se trata da determinação de qualquer espécie em nível traço. No caso de amostras derivadas do petróleo, diversos procedimentos vem sendo empregados para o pré-tratamento visando a determinação de elementos traços tais como a extração induzida por quebra da emulsão, [6][7][8] a digestão ácida, 9-11 a diluição com solventes adequados, [12][13] a conversão das amostras em emulsões ou microemulsões [14][15][16][17][18] que possam, posteriormente, ser introduzidas em diferentes instrumentos.…”

Elements Content in Otolith as Pollution Indicator for Cultured Sea Bass (Lates calcarifer) of Malaysia

“…The only safe Cd level in water is in St 20 which is below 0.05 mg·L -1 in Class 2 & E. According to Ooi et al (2005) [30], water quality of St 3 was classified as Class 3 of IMWQS with the present of organic matter and oil leaching form the boat passing by and port at the jetty deteriorate this area (Table 3 thus, a major input of Zn in group A might be tourism activities as there is a high Zn content in the diesel fuel used in boats around Langkawi Island. Cassella et al [31] found that Zn content in diesel is generally abundant. The fuel used in boating activities enters the water through direct disposal by the boatman or through leakage from the engine into the water [32].…”

“…Numerous studies proved that trace elements uptake onto otolith were from ambient water [7,[22][23][24][25][26][27][28][29][30][31][32][33][34]. Foreign elements except Ca mainly from ambient water undergo complex pathways such as blood plasma and membrane before incorporated onto otolith [27].…”

Use of Constrained Mixture Design in the Optimization of a Method Based on Extraction Induced by Emulsion Breaking for the Determination of Ca, Mg, Mn, Fe and Zn from Palm Oil by Flame Atomic Absorption Spectrometry

“…Not only is this interface exchange phenomenon of substances between phases favored by increasing contact area, but also by interaction forces dependent on the nature of this substance (polar or nonpolar). 9 Extraction induced by emulsion breaking 10 has been applied in edible oils for the determination of Cr and Mn by graphite furnace atomic absorption spectrometry (GFAAS), 11 in edible oils from Turkey for the determination of Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn using inductively coupled plasma optical emission spectrometry (ICP OES), 12 trace concentrations of Cu, Mn and Ni in biodiesel by GFAAS, 13 Cu, Fe and Mn in used lubricating oils by flame atomic absorption spectrometry (FAAS), 14 zinc from diesel after multivariate optimization 15 and edible oils by FAAS. 8 This study proposes the application of EIEB for the determination of Ca, Mg, Mn, Fe and Zn from palm oil samples by FAAS.…”