A system for producing ammonia comprises a reactor configured for receiving nitrogen feed gas and hydrogen feed gas, the reactor comprising a catalyst configured to convert at least a portion of the nitrogen gas and at least a portion of the hydrogen feed gas to ammonia to form a reactant mixture comprising the ammonia and unreacted nitrogen feed gas and unreacted hydrogen feed gas, an adsorbent configured to selective adsorb at least a portion of the ammonia from the reactant mixture, and a recycle line to recycle the unreacted nitrogen feed gas, the unreacted hydrogen feed gas, and unabsorbed ammonia to the reactor.