Paper

Comparative Technoeconomic Analysis of Conventional and Absorbent-Enhanced Ammonia Synthesis

Ammonia is the second-most produced synthetic chemical and the main precursor for nitrogen-based fertilizer. In 2015, 160 million tons were produced globally, and global demand is expected to grow 1.5% annually until 2050 [1]. However, traditional ammonia production uses natural gas or coal as its hydrogen source, and as a result, is also responsible for more than 1% of global GHG emissions and 5% of global natural gas consumption [2]. Clearly, a more sustainable ammonia production scheme is needed. One such alternative is obtain hydrogen from electrolysis powered by wind- or solar-derived electricity. It has been proposed to perform this…

Paper

Ammonia Absorbents with High Stability and High Capacity for Fast Cycling

Ammonia absorption is an alternative separation to condensation in ammonia production. Metal chloride salts selectively incorporate ammonia into their crystal lattices with remarkably high capacity. Regeneration and stability of these salts are further improved by dispersing them onto a porous silica support. Here, we discuss the optimal preparation methods of supported metal halides, as well as optimal conditions for uptake and release of ammonia. The metal halide salt particle size, support particle size, support composition and preparation methods are optimized for material stability, speed of uptake and release, and maximum ammonia capacity. An automated system was used to rapidly screen…