Review of hydrogen production using chemical-looping technology

Hydrogen is an attractive energy carrier due to its potentially high energy efficiency and low generation of pollutants, which can be used for transportation and stationary power generation. However, hydrogen is not readily available in sufficient quantities and the production cost is still high. Steam methane reforming (SMR) process is now the most widely used technology for H₂ production, but this process is complex and cannot get thorough carbon capture. Hydrogen production using chemical looping technology has received a great deal of attention in recent years because it can produce hydrogen with higher process efficiency and can capture carbon dioxide. Many researchers have carried out intensive research work on the hydrogen production processes using chemical looping technology. Based on the previous studies stated in the literature, the authors try to give an overview on the recent advances of two categories, chemical looping reforming (CLR) and chemical looping hydrogen production (CLH) processes. Besides, the characteristics of the processes are pointed out based on the comparison with the conventional SMR process. The existing technical problems and the aspects of future research of each approach are also summarized.