Cleaning agent for removing impurity oxygen in reducing gases including synthesis gas and the like as well as preparation method and application of cleaning agent

The invention discloses a cleaning agent for removing impurity oxygen in reducing gases including synthesis gas and the like as well as a preparation method and application of the cleaning agent. The cleaning agent consists of active ingredients and a carrier, wherein the general formula of the cleaning agent is CuZnCa(O)-carrier; in CuZnCa(O), the molar ratio of Cu/Zn/Ca is 1/(0.05-0.4)/(0.2-0.7); in a mass ratio, the carrier/CuO is (1.8-2.3)/1. The preparation method of the cleaning agent is a co-precipitation method. The application conditions of the cleaning agent include a reaction temperature of 110 DEG C-320 DEG C, reaction pressure of 0Mpa-6.0MPa, and reaction air velocity of 100h-10000h. According to the invention, the produced fine deoxidizing agent is enabled to have higher pressure measuring intensity on the premise that the production cost is lower; meanwhile, the residual oxygen amount in the purified gas is lower, so that the existing requirements for removing the impurity oxygen in the