Greener procedures for biodiesel quality control

Abstract

Biodiesel analysis often requires large amounts of chemicals and organic solvents with consequent generation of large waste volumes. However, several environmentally friendly alternatives have been presented for assay of biodiesel quality control parameters. These approaches include direct analysis with reagentless procedures, improved sample preparation by dilution or analyte extraction with nontoxic solvents, preparation of emulsions or microemulsions, and sample mineralisation under mild conditions as well as strategies for minimization of reagent consumption and waste generation. These greener alternatives are critically reviewed, highlighting the advantages and limitations of each approach in biodiesel analysis. Alternative analytical techniques (e.g. flow analysis and electrochemical detection), predictive studies, and measurement of physicochemical parameters are also discussed. A two-nozzle FBMN for nebulisation of biodiesel samples and water, avoiding acid digestion Ca, K, Mg, Na, and P: 0.005-0.5; minor components: 0.001-3 45 4400 | Anal. Methods, 2015, 7, 4396-4418 This journal is

Identification of biodiesel feedstock in biodiesel/diesel blends using digital images and chemometric methods

“…Compared to the others, the proposed methodology has great advantages: the low cost of a simple webcam used as the detector, following the principles of "Green Analytical Chemistry (GAC)", simple, fast, inexpensive and non-destructive approaches, not producing residues and avoiding time spent in waste treatment, without hindering the fundamental analytical features. 18 In addition, an extension of the proposed methodology for increasing contents of biodiesel in diesel (higher than B5, in this case) tends to facilitate its discrimination, as described elsewhere. 9-11 Thus, the proposed methodology can be potentially applied for other applications, such as quantication of the biodiesel content in the BDB, and also for identication/quantication of adulterations of biodiesel and BDB samples with vegetable oils.…”

Fast Spectrophotometric Determination of Iodine Value in Biodiesel and Vegetable Oils

“…These characteristics make the procedure attractive for analysis of biodiesel and vegetable oils directly at the production plants, also because of the environmental friendliness. 20 A quantitative spot test based on digital images was recently proposed for determination of iodine value in biodiesel with negligible reagent consumption and waste generation. 13 Although a good analytical performance was attained, the proposal described herein has advantages in relation to detection limit (ca.…”

Liquid–liquid microextraction in sequential injection analysis for the direct spectrophotometric determination of acid number in biodiesel

“…Although the contributions of flow analysis to fuel quality control have been highlighted [16], its application to biodiesel analysis is yet limited [17]. Aiming at the spectrophotometric acid number determination, a sequential injection analysis (SIA) system was proposed [18].…”