Evaluation of various corn variety kernels for hydrogen gas production by APR

Abstract

The present study was designed to evaluate gasification performances of various corn kernel varieties (field corn, non-genetically modified (non-GMO) field corn, yellow field corn, white field corn and popcorn) for hydrogen gas production by aqueous-phase reforming (APR) using activated carbon supported platinum catalyst.Corn kernels were solubilized in 200°C-subcritical water medium under 13.79 MPa CO2 pressure before use. The hydrolysates obtained from hydrolysis process were rich in total organic carbons (TOC) with a 5200–5850 mg/L concentration range. There were significant differences among varieties in terms of overall solubilization. However, hydrolysates from different corn varieties produced the same amount of hydrogen gas with a yield of 130 mL/g corn on average. The gas chromatography-mass spectrometry (GC-MS) analysis of corn hydrolysates showed considerable decreases in the peak areas after APR compared to initial hydrolysates. These decreases indicate consuming most of the corresponding organics in the gasification process. Evaluation of gasification results based on carbon balance showed that only small fractions of organic carbons converted to carbon-containing gaseous products (CO and CO2) and remaining carbons were precipitated as ungasified solid residue. Thus, gas mixtures produced from corn kernel hydrolysates were mostly composed of hydrogen as found in gas analysis.