Issue 17, 2015

Ultrasound-assisted digestion of biodiesel samples for determination of metals by stripping voltammetry

Abstract

The ultrasound-assisted digestion of biodiesel samples is demonstrated for the first time. The efficiency of the proposed sample preparation method was evaluated for trace metal determination by stripping voltammetric techniques, which are more susceptible to residual carbon content (RCC) in digestates. Biodiesel samples (50–75 mg) were treated in glass tubes, with a mixture of 3.0 mL of concentrated HCl and 4.5 mL of H2O2, placed inside an ultrasonic bath (40 kHz frequency and 120 W) exactly over the region of higher ultrasound intensity and sonicated for 40 min. These parameters were optimized using factorial design experiments for the analysis of spiked samples. Recovery values between 94 and 108% for zinc, cadmium, lead, copper and mercury were verified under optimized conditions. RCC values after US-assisted digestions were in the range of 3.05–3.75% using covered glass tubes, which are acceptable values for the accurate voltammetric determination of metals. These results indicate that the proposed sample preparation method presents comparable performance to traditional or microwave-assisted acid digestions and can be associated with on-site electroanalysis using screen-printed electrodes.

Graphical abstract: Ultrasound-assisted digestion of biodiesel samples for determination of metals by stripping voltammetry

Article information

Article type
Paper
Submitted
29 Way 2014
Accepted
05 Kax 2014
First published
05 Kax 2014

Anal. Methods, 2015,7, 7170-7176

Author version available

Ultrasound-assisted digestion of biodiesel samples for determination of metals by stripping voltammetry

H. C. Freitas, E. S. Almeida, T. F. Tormin, E. M. Richter and R. A. A. Munoz, Anal. Methods, 2015, 7, 7170 DOI: 10.1039/C4AY02313G

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements