Phthalates in Black Liquor from Cellulose Production from Pineapple (Ananas Comosus: Elimination from Effluents and Mechanism of Formation)

Black liquor is a residue from conventional cellulose extraction. In the present work, we used a black liquor obtained after the cellulose extraction from pineapple leaves (Anana comosus) to recover phytochemicals after a simple pretreatment based on evaporation with sunlight. In a later ethanolic extraction we identified the main hydrophobic components by spectroscopic procedures. According to the Fourier Transform Infrared Spectrometry (FTIR) analysis, raw black liquor was mainly composed of glycerides and lignin fragments that were not recovered in the ethanolic extract. Three classes of compounds were detected based on HPLC-MS: class 1 compounds included highly polar structures as phenylpropane diglycerides, class 2 corresponded to typical residues from meteorized phthalates and class 3 were compounds with low polarity that corresponded to lignin derivates. The presence of phthalates was an evidence of plastic material transfer to living tissues; in this case, correlated with mulching. The occurrence of these plastic residues was explained by analyzing the weathering and decomposition of mulching materials. In addition, a theoretical model for the release of plastic fragments upon reaction with environmentally formed radical species was presented using computational chemistry methods based on Density Functional Theory. This research contributed to a circular economy strategy which recovers cellulose and reduces the accumulation of phthalates in soil; also, it could trigger the development of purification strategies to obtain pineapple phytochemicals and validate their potential benefits to human health.