Tsubame BHB Co., Ltd. (Head Office: Chuo-ku, Tokyo; Representative Director CEO: Masahiro Watanabe; hereinafter referred to as “the Company”) has signed a joint evaluation contract with Mitsubishi Chemical Corporation (Headquarters: Chiyoda-ku, Tokyo; President & CEO: Masayuki Waga) (hereinafter referred to as “MCC”), which has zeolite membrane technology for selectively separating ammonia, to realize a small ammonia production process using a separation membrane.

Development of MCC’s ammonia separation membrane was jointly developed by Tokyo Institute of Technology Professor Emeritus, et. al., through the ACCEL^Note1) Strategic Basic Research Program by the Japan Science and Technology Agency “Materials Science and Application of Electrides” (Research Director: Hideo Hosono, Program Manager: Toshiharu Yokoyama), and the Company has promoted ammonia business using an electride catalyst that was also discovered and invented by the said ACCEL, so this relationship has already shown a synergistic effect.

Figure: Image of a reaction separation type process using a zeolite separation membrane

The ammonia production reaction is an equilibrium reaction. The problem with this is that, theoretically, the ammonia concentration cannot be increased beyond the equilibrium composition. Therefore, the existing Haber-Bosch method (hereinafter referred to as the “HB method”) contains a recycling process that returns the unreacted raw materials hydrogen and nitrogen to the reactor, which requires large-scale processes and expensive equipment. Therefore, if a reaction-separation type process can be developed where the produced ammonia is separated using a membrane, the conversion of raw materials in the reactor may significantly increase, which would reduce the recycling process and, in turn, reduce the size and cost of the plant.

In the future, the Company and MCC will acquire various data such as related to long-term durability, process design, and optimization through this joint evaluation for realizing practical use, and will prepare for the realization of an ultra-small on-site ammonia production process.

Currently, ammonia is produced mainly by using the HB method which was discovered more than 100 years ago. The HB method is an extremely outstanding production technology capable of synthesizing ammonia from only nitrogen in the air and hydrogen^{Note 2)} obtained from substances such as natural gas. This method is widely used throughout the world. On the other hand, the HB method requires high-temperature and high-pressure reaction conditions. When using this method, intensive mass production must be performed in large-scale plants with high energy loads. This creates the issue of large facilities investment. Furthermore, dedicated transportation equipment and storage facilities are required in order to transport ammonia from production sites to areas of demand throughout the world. This results in the issue of extremely high logistics costs.

The electride catalyst invented to solve this issue is characterized by high-efficiency ammonia synthesis under low temperature and low pressure conditions. These low-temperature and low-pressure reaction conditions enable production in small-scale plants with annual output of several tens of thousands of tons or less. Such small-scale production was previously difficult when using the HB method^{Note 3)}. In the future, the practical application of this technology is expected to realize an on-site ammonia production model that produces the required amount of ammonia at the location where the ammonia is needed.

―――――――――――――

^{Note 1)} A program run by the Japan Science and Technology Agency. From among the world’s leading outstanding research results, the program extracts results for which risk assessment is difficult by corporations and other organizations. Through innovation-oriented R&D management by a program manager, the program connects the R&D flow to corporations, venture corporations, and other business.

^{Note 2)} The most abundant element in the universe. In recent years, the technology has attracted attention as for use in generating clean energy such as fuel for fuel cell vehicles.

^{Note 3)} Generally, ammonia production using the HB method requires a production scale larger than annual output of several tens of thousands of tons.

Press release PDF