Miniaturized electrocoagulation approach for removal of polymeric pigments and selective analysis of non- and mono-hydroxylated phenolic acids in wine with HPLC-UV

Abstract

Electrocoagulation (EC) approach was developed to allow fast sample clean-up step prior to selective analysis of non- and mono-hydroxylated phenolic acids in red wine samples with high performance liquid chromatography hyphenated with UV detection (HPLC-UV).

Development of a new paper-based voltage step electrocoagulation technique and application to wine classification

“…2C. In general, the intensity values decrease with the increasing voltages which can be explained by the stronger bleaching effect at higher voltages 20 as well as the green sludge production at the anode. The images and corresponding plots obtained by performing VSEC using the CAS to treat the same wine sample are shown in Fig.…”

“…(4) Electrochemical oxidation and reduction of wine compounds resulting in red color bleaching, as well as different products, such as amino acids and other oxidized compounds and polymeric species from phenolic compound oxidation and polymerization. 20 Aluminium electrodes were required to effectively provide these proposed mechanisms which could not occur using an electrochemically inert electrode such as platinum. 20 Due to these already investigated mechanisms as well as the low cost and flexibility of the material, aluminium was selected for the experiments in this study.…”

“…20 Aluminium electrodes were required to effectively provide these proposed mechanisms which could not occur using an electrochemically inert electrode such as platinum. 20 Due to these already investigated mechanisms as well as the low cost and flexibility of the material, aluminium was selected for the experiments in this study. On-paper VSEC mechanisms could also be expected to be the same albeit with variation of the local voltages along the CAS which could lead to different degrees of EC and could be observed with the different red color intensities along the paper containing the treated wine sample.…”

“…The oxidation has already been recognized to mainly result in electrode corrosion and sludge formation including the products from wine oxidation such as amino acids, oxidized phenolic compounds and polymeric species. 20,26 The reduction mechanism on filter paper during the VSEC was proven here based on investigation of the known active species of metal ions. To this end, the filter papers were immersed in 1 mM of different heavy metal solutions including Co 2+ , Ni 2+ , and Zn 2+ in 0.1 M KCl (aq) .…”

Recent Applications of the Electrocoagulation Process on Agro-Based Industrial Wastewater: A Review

“…It forms black liquor as the main by-product, which contains about 50% lignin. The pulp and paper industry discards lignin to make a good quality of paper [98]. The release of lignin comes from the process of alkaline extraction at the bleaching stage.…”