RESEARCH ARTICLE Equation Chapter 1 Section 1Use of cork granules as an effective sustainable material to clean-up spills of crude oil and derivatives Diego Todescato 1,2 & Fabíola V. Hackbarth 2 & Pedro J. Carvalho 3 & Antônio A. Ulson de Souza 2 & Selene M. A. G. Ulson de Souza 2 & Rui A.R. Boaventura 1 & Miguel A. Granato 4 & Vítor J. P. Vilar 1 Received: 24 January 2019 /Accepted: 10 October 2019 # Springer-Verlag GmbH Germany, part of Springer Nature 2019 Abstract The use of cork granules for cleaning up crude oil or oil derivative spills and further oil recovery appears as a promising option due to their unique properties, which allow a high oil sorption capacity, low water pickup and excellent reuse. The present work reports the effect of oil viscosity on cork sorption capacity by using five types of oils (lubricating oil, 5.7 g oil g cork -1 ; heavy oil, 4.2 g oil g cork -1 ; light oil, 3.0 g oil g cork -1 ; biodiesel, 2.6 g oil g cork -1 ; and diesel, 2.0 g oil g cork -1 ). The cork sorption capacity for light petroleum was also evaluated as a function of temperature and sorbent particle size. Additionally, improvements on oil recovery from cork sorbents by a mechanical compression process have been achieved as a result of a design of experiments (DOE) using the response surface methodology. Such statistical technique provided remarkable results in terms of cork sorbent reusability, as the oil sorption capacity was preserved after 30 cycles of sorption-squeezing steps. The sorbed oils could be removed from the sorbent surface, collected simply by squeezing the cork granules and further reused. The best operational region yielded near 80% oil recovery, using a cork mass of 8.85 g (particle size of 2.0–4.0 mm) loaded with 43.5 mL of lubricating oil, at 5.4 bar, utilising two compressions with a duration of 2 min each. Keywords Cork . Oil spill . Crude oil and oil derivatives . Oil sorption . Oil recovery Introduction Oil spills are a very dangerous event for the aquatic ecosystem as life-forms’ existence is severely threatened. By definition, oil spills include any spill of crude oil or oil distilled products that can pollute the surface of the land, air and water environ- ments. The term is usually associated with marine oil spills, where oil is released into the ocean and coastal waters (Fingas 2013). Several products/techniques, such as dispersants, sorbents, solidifiers, booms and skimmers, have been developed to sep- arate oil from water aiming at cleaning accidental oil spills (Adebajo et al. 2003; Bandura et al. 2015; Broje and Keller 2006; Fingas 2013). Sorbents are materials that recover oil through either ab- sorption or adsorption. The term ‘sorption’ is used to refer to both processes. Oil sorbents comprise a wide range of organic or inorganic products, from natural sources (such as bark, peat, sawdust, cork, paper-pulp, pumice and vermiculite) (Behnood et al. 2013; Galblaub et al. 2016; Olga et al. 2014: Saito et al. 2003) or synthetic (polypropylene, polyester, zeo- lites) (Bandura et al. 2015, 2017; Oribayo et al. 2017; Ozan Aydin and Bulbul Sonmez 2015). To be useful in cleaning oil spills, sorbents need to be both oleophilic (oil-attracting) and hydrophobic (water-repellent) (Wu et al. 2014). Although they can be used as the sole clean-up method in small spills, Responsible editor: Philippe Garrigues Electronic supplementary material The online version of this article (https://doi.org/10.1007/s11356-019-06743-1) contains supplementary material, which is available to authorized users. * Vítor J. P. Vilar vilar@fe.up.pt 1 Laboratory of Separation and Reaction Engineering-Laboratory of Catalysis and Materials (LSRE-LCM), Chemical Engineering Department, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal 2 Laboratory of Mass Transfer, Federal University of Santa Catarina, PO Box 476, Florianópolis, SC CEP 88040-900, Brazil 3 CICECO-Aveiro Institute of Materials, Department of Chemistry, University of Aveiro, 3810-193 Aveiro, Portugal 4 Departamento de Engenharias, Universidade Federal de Santa Catarina (UFSC), Campus Blumenau, Blumenau, SC, Brazil Environmental Science and Pollution Research https://doi.org/10.1007/s11356-019-06743-1