Olive mill wastewater (OMW) is a pollutant effluent of the olive oil production. To reduce the environmental impact of this agro-industrial sector, with simultaneous valorization of such waste, the steam reforming of OMW (OMWSR) was studied in this work. Besides the reduction of pollution resulting from OMW, the process allows producing “green” H2. In this study, several commercial catalysts (Ni-, Cu–Zn- and noble metal-based) were tested to compare their performances. A catalytic screening study with all the commercial catalysts was performed, and stability tests were conducted with the material that demonstrated higher activity (Rh-based catalyst). The physicochemical characterization of the fresh and spent materials was realized through several techniques (temperature-programmed reduction, temperature-programmed oxidation, transmission electron microscopy, temperature-programmed desorption of CO2, temperature-programmed desorption of NH3, chemisorption of H2, scanning electron microscopy with energy dispersive spectroscopy and physical adsorption of N2 at −196 °C). Although there are some materials with good catalytic performance, the Rh-based sample stood out during the tests, exhibiting high catalytic activity and high stability: at 400 °C the H2 yield (over 9 molH2·molOMW−1) and total organic carbon (TOC) conversion (>98%) were high along all the 24 h of the stability test. Besides that, several Ni-containing catalysts were prepared and tested to compare their performances for the OMWSR; still, stability tests were also carried out. The materials were also extensively characterized. Amongst the materials tested, the Ni–Ru/SiO2 sample stood out, exhibiting high catalytic performance: at 400 °C, the H2 yield (>8 molH2·molOMW-1) and conversion of total organic carbon (≈75%) were high during all the 24 h of the long-term test, with only a small deactivation being noticed.
- Properties of the catalysts that effect the catalytic activities of the materials in a steam reforming process.
- Solution for valorization of the Olive Oil Mill Wastewater.