Ultrasound-assisted ionic liquid dispersive liquid-liquid microextraction for Na, K, Ca, Mg and P determination in biodiesel by ICP-OES

N. KOVACHEV; C. DOMINI; M. A. AGUIRRE ; A. CANALS; F. D. ÁVILA-OROZCO; I. P. ROMÁN

Congreso; XXV RNE IX CIE; 2016

Biodiesel is a composed mixture of fatty acid alkyl esters derived from vegetable oils (i.e. soybean, sunflower, palm, etc.) or animal fats. Because of their properties, biodiesel is completely miscible with diesel [1]. This biofuel is a renewable substitute (biodegradable and non toxic) that can be used in diesel engines without the need of modifications or adaptations [2]. Throughout biodiesel production, contamination may occur with metals such as Na, K, Ca, Mg, sulfur and phosphorus compounds. These contaminants could influence the stability and and other physical-chemical properties [3,4].The aim of this work was to develop a green sample preparation method based on an ultrasound assisted ionic liquid dispersive liquid liquid microextraction technique (USA-IL-DLLME) for Na, K, Ca, Mg and P determination in biodiesel samples by ICP-OES. The extraction was optimized using a two steps approach: (i) Plackett-Burman design, and (ii) central composite design. The optimized 3 solution, C10MIM][Cl] and sonication power and time, 45 W and 1 min, respectively. Under the optimized conditions biodiesel samples from different feedstock such as sunflower, corn, soybeanand grape seed oils, via a base catalyst transesterification, were analyzed and relative standard deviation values were lower than 10% and recovery values ranged between 95% and 106%.