3D printed lab-scale raceway ponds reactors for photo-Fenton processes

Abstract Raceway pond reactors (RPRs) have been widely used in microalgae mass culture (Acien et al., 2013) and their application for micro pollutant removal in photo-Fenton processes has been recently assessed (Rivas et al., 2015). The main advantages of raceway pond reactors are being low cost, robust and flexible (Carra et al. 2015). The modeling and testing of such reactors, in particular their prototyping can benefit from additive manufacturing. However, the preparation of RPRs by 3D printing to study photo-Fenton reactions has not been investigated. In this work, two different printable materials, PLA (polylactic acid) and Timberfill were evaluated in terms of chemical resistance to photo-Fenton reactants. First, these raw materials were exposed to H2O2 solutions at pH=3 and to sunlight to simulate photo-Fenton environment. TOC analysis showed that both PLA and Timberfill did not alter the concentration of TOC of the solution in the presence of H2O2 and iron. Furthermore, printed lab-scale raceway ponds were examined under similar conditions. Through different assays, TOC remained constant during operation, and no organic matter contaminated the solution from its container. This work shows the promising capability of PLA to be used as photo-Fenton reactor; some limitations found are discussed and further research is indicated. References Acién Fernández, F.G., Fernández Sevilla J.M., and Molina Grima E. (2013), Photobioreactors for the production of microalgae. Reviews in Environmental Science and Bio/Technology, 12(2), 131-151. Carra I., Sirtori C., Ponce-Robles L., Sánchez Pérez J.A., Malato S. and Agüera A. (2015), Degradation and monitoring of acetamiprid, thiabendazole and their transformation products in an agro-food industry effluent during solar photo-Fenton treatment in a raceway pond reactor. Chemosphere, 130, 73 - 81. Rivas G., Carra I., García Sánchez J.L., Casas López J.L., Malato S. and Sánchez Pérez J.A. (2015), Modelling of the operation of raceway pond reactors for micropollutant removal by solar photo-Fenton as a function of photon absorption, Applied Catalysis B: Environmental, 178, 210-217.