Binder jetting 3D printing of monolithic Zeolite 13X adsorbents

This study demonstrates, for the first time, the successful fabrication, using binder jetting (a 3D printing process), of monolithic zeolite adsorbents. The characteristics of raw powder (Zeolite 13X), printed samples, and calcined samples at different temperatures were evaluated and compared. The calcined sample at 750°C exhibited a balanced performance between adsorption and mechanical strength. First, this sample retained the granular morphology and crystalline structure of the raw powder as confirmed by scanning electron microscopy and X-ray diffraction analysis. Thermogravimetric analysis validated the effective removal of organic binders in this sample. Compared with the raw powder, nitrogen adsorption showed that this sample had a decrease in specific surface area (from 848 to 383 m 2 /g) and micropore volume (from 0.3854 to 0.1402 cm 3 /g), accompanied by an increase in mesopore volume (from 0.0041 to 0.0851 cm 3 /g). This sample achieved a CO 2 adsorption capacity of 2.65 mmol/g at 25°C and 1 bar while maintaining a notable CO 2 /N 2 selectivity of 1390 based on ideal adsorption solution theory under these conditions, which approaches that of the raw powder. Moreover, mechanical testing following ASTM standards showed that this sample exhibited a compressive strength of 0.45 MPa at room temperature, which is expected to suffice certain adsorption applications. Additionally, the successful fabrication of complex geometries highlights the versatility of binder jetting and confirms its feasibility for producing mechanically stable zeolite adsorbents.