Paper recycling has increased in recent years. A principal consequence of this process is the problem of addressing polymeric components known as stickies. A deep characterization of stickies sampled over one year in a recycled paper industry in México was performed. Based on their chemical structure, an enzymatic assay was performed using lipases. Compounds found in stickies by Fourier-Transform Infrared spectrometry were poly (butyl-acrylate), dioctyl phthalate, poly (vinyl-acetate), and poly (vinyl-acrylate). Pulp with 4% consistency and pH=6.2 was sampled directly from the mill once macro stickies were removed. Stickies were quantified by counting the tacky macrostructures in the liquid fraction of the pulp using a Neubauer chamber before the paper was made, and they were analyzed with rhodamine dye and a UV lamp. Of the two enzymes evaluated, the best treatment condition used Lipase 30G at a concentration of 0.44 g/L, which produced a 35.59% decrease in stickies. SebOil DG showed a smaller stickies reduction of 21.5% when used at a concentration of 0.33 g/L. Stickies in kraft paper processes were actively controlled by the action of lipases, and future research should focus on how this enzyme recognizes its substrate and should apply synthetic biology to improve lipase specificity.
Keywords:
Subject: Biology and Life Sciences - Biology and Biotechnology
Copyright: This open access article is published under a Creative Commons CC BY 4.0 license, which permit the free download, distribution, and reuse, provided that the author and preprint are cited in any reuse.
Preprints.org is a free preprint server supported by MDPI in Basel, Switzerland.