A Zeolitic Octahedral Metal Oxide with Ultra-Microporosity for Inverse CO /C H Separation at High Temperature and Humidity.

Separation of CO /C H to obtain pure C H presents a challenge for the chemical industry. CO -selective adsorbents are favored because of the convenient separation process. However, there are only a few CO -selective adsorbents that can effectively isolate CO from CO /C H , and there is almost no research on CO /C H separation under harsh conditions, such as with high temperatures and humidities. Herein, a zeolitic octahedral metal oxide based on ϵ-Keggin polyoxometalates is utilized for separations of CO /C H at high temperatures and humidities. Single gas adsorption measurements show that the material only adsorbs CO with almost no C H taken up. Dynamic competitive adsorption experiments show that the material efficiently separates CO /C H , and highly pure C H is obtained directly. The robust material maintains a high separation performance at 333 K with 18.12 % water. The high stability of the material enables reuse without loss of separation performance.