Facile Preparation of Cu(I)/5A via One-Step Impregnation with Highly Dispersed CuCl in Ethanol Single Solvent toward Selective Adsorption of CO from H2 Stream

Cuprous ion-based zeolites have been proven as promising carbon monoxide (CO) adsorbents by virtue of their excellent adsorption and regeneration properties due to pi complex-ation. However, existing preparation methods still suffer from the problems of a cumbersome process and low loading amounts of cuprous ions. Herein, we proposed a one-step synthesis strategy of using ethanol as a solvent to provide a reducing protective environment, which enabled the facile and controllable preparation of highly dispersed CuCl over 5A zeolites. Using CuCl as a copper source, to ensure the integrity of the 5A zeolite structure, CuCl species were directly loaded onto the 5A support in one step. Ethanol solution could effectively protect Cu(I) from being oxidized by oxygen in air and improve the stability of cuprous ions in Cu(I)/ 5A adsorbents. The results demonstrated that the Cu(I)/5A prepared by this method exhibited a superior CO adsorption performance to the pristine 5A zeolite. The adsorption capacity of CO over Cu(I)/5A attained 3.44 mmolmiddotg-1 at 298 K and atmospheric pressure, which was evidently superior to those of CuY (2.7 mmolmiddotg-1) and CuSAPO34 (1.84 mmolmiddotg-1) reported in the literature, while the adsorption capacity of H2 was only 0.069 mmolmiddotg-1 under the same condition. According to the ideal solution adsorption theoretical model, CO was preferentially adsorbed and the IAST selectivity of CO in the CO/H2 binary mixture over Cu(I)/5A was about 273.4. This study provides a novel and effective way to synthesize high-efficiency CO adsorbents.

Automated summary

In this study, a one-step synthesis strategy using ethanol as a solvent was proposed to prepare highly dispersed CuCl loaded on 5A zeolite, which improved the CO adsorption performance. The ethanol solution effectively protected Cu(I) from oxidation and enhanced the stability of cuprous ions in Cu(I)/5A adsorbents.