Application of NaOH modified micro-polyethylene as storage material for H2

Abstract

H2 is increasingly regarded as a decarbonized solution for the increasing energy demand. However, due to its low density, H2 cannot be easily compressed, and there is a need for materials that can store large amounts of H2. Here we tested H2 adsorption capacity of micro-polyethylene (MicroPE) – a significant environmental pollutant - at 1–70 bar and 30 °C. H2 adsorption capacity increased with increasing the adsorption pressure (from 0.06 mol/kg at 17.21 bar to 0.20 mol/kg at 68.11 bar for raw MicroPE). MicroPE activated with aqueous NaOH significantly changed H2 adsorption under the same operating conditions. H2 adsorption increased to 0.50 mol/kg at 68.11 bar when MicroPE was treated with 0.002 mol/L aqueous NaOH. We conclude that MicroPE is a feasible material to store H2, competitive to other storage materials in in terms of the availability, cost-effective, environmental pollution mitigation and slightly higher H2 adsorption rates under the condition studied. This work provides fundamental information, and thus aids in the reduction of environmental microplastic pollution, while further enabling a green energy transition.