The quantification of H2, CO2 and CH4 was achieved with a gas chromatograph (GC-2014, Shimadzu, Japan), which was equipped with two different separation and detection pathways. The CO2 and CH4 were separated with a Porapak Q column (CS-Chromatographie Service Gmbh, Manufacturer Item No.: 662, Langerwehe, Germany) and quantified with a thermal conductivity detector by using helium as carrier gas. The H2 gas was separated with a ShinCarbon ST Packed Column (Restek Cat#80486-800, Bellafonte, Pennsylvania, USA),