2.4.1. Volatile organic compounds

VOC photodegradation reactions were conducted in a Pyrex glass cylindrical reactor with a diameter of 200 mm and an effective volume of 5 L [38]. A 100-cm<sup>2</sup> digital inkjet-printed sample or jet-sprayed sample was placed at the bottom of the reactor and exposed to a 500-W iron halogen lamp (HG 500, 315–400 nm, UV-A, Jelosil, Milan, Italy). The reactor had two entrances, one for VOC loading and the other for sampling by a gas chromatograph (490 Micro GC System, Agilent Technologies Italia S.p.A, Milan, Italy).

Ethanol and toluene were selected as model pollutants, and the initial concentration for both was 400 ppm for each test. The photodegradation tests were conducted for 6 h.
