Parametric study on the steam reforming of phenol-PET solution to hydrogen production over Ni promoted on Al2O3-La2O3 catalyst

Abstract Production of hydrogen from plastic waste could be a prospective key to the ecological problems resulted from waste. To further explore the process, a 32-runs parametric study on the steam reforming of Polyethylene terephthalate (PET) dissolved in phenol was conducted in a fixed bed reactor using Ni over La 2 O 3 -Al 2 O 3 support. The five factors studied were temperature (A), feed flow rate (B), mass flow (C), phenol concentration (D), and concentration of PET solution (E), whereas the responses were phenol conversion (Y 1 ) and hydrogen selectivity (Y 2 ). From the result, it was observed that significant influence resulted for all the main independent variables on the dependent variable of Y 1 and Y 2 with the range of 47.24–97.6% and 49–70.96%, respectively. Moreover, the Y 1 and Y 2 responses have influenced by some interaction variables like AC, CD, CE, ACE, and BCE. As evident from the design, initial variables such as 800 °C, 0.10 ml/min feed flow rate, 10 SCCM mass flow, 10 wt.% of phenol in the feed, and 7% PET concentration were the best preliminary conditions that formed maximum Y 1 (94%) and Y 2 (71%) responses. However, analyses on the product composition revealed that high amount of aliphatic branched-chains along with moderate amount of cyclic compounds were produced from steam reforming of PET-phenol. Due to the short retention time of the compounds on the catalysts bed, the aromatization of PET cracking products was small.