Extrusion-Based 3D Printing of Molecular Sieve Zeolite for Gas Adsorption Applications

Abstract

Extrusion based 3D printing is one of the emerging additive manufacturing technologies used for printing range of materials from metal to ceramics. In this study, we developed a customized 3D printer based on extrusion freeform fabrication technique, such as slurry deposition, for 3D printing of different molecular sieve zeolite monoliths like 3A, 4A, 5A and 13X to evaluate their performance in gas adsorption. The physical and structural properties of 3D printed zeolite monoliths will be characterized along with the gas adsorption performance. The Brunauer-Emmett-Teller (BET) test of 3D printed samples will be performed for calculation of the surface area, which will give us the capacity of gas absorption into 3D printed zeolite. The BET surface area test showed good results for Zeolite 13X compared to available literature. The surface area calculated for 3D -printed Zeolite 13X was 767m 2 /g and available literature showed 498 m 2 /g for 3D -printed Zeolite 13X. The microhardness values of 3D -printed Zeolite samples were measured using a Vicker hardness tester. The hardness value of the 3D -printed Zeolite samples increased from 8.3 ± 2 to 12.5 ± 3 HV 0.05 for Zeolite 13X, 3.3 ± 1 to 7.3 ± 1 HV 0.05 for Zeolite 3A, 4.3 ± 2 to 7.5 ± 2 HV 0.05 for Zeolite 4A, 7.4 ± 1 to 14.0 ± 0.5 HV 0.05 for Zeolite 5A, before and after sintering process, respectively. The SEM analysis was performed for 3D printed samples before and after sintering to evaluate their structural properties. The SEM analysis reveals that all 3D -printed Zeolite samples retained their microstructure after slurry preparation and also after the sintering process. The porous nature of 3D -printed Zeolite walls was retained after the sintering process.

Effects of Cold Sintering on the Performance of Zeolite 13X as a Consolidated Adsorbent for Cesium

“…Compressed zeolite 13X pellets (Z1) were formed under the application of 500 MPa of pressure using a uniaxial press (CARVER). Subsequently, sintered zeolite 13X pellets (Z2) were produced by treating Z1 pellets at 700 °C in a box furnace for 4 h, following the temperature profile shown in Figure S1a, with additional details of heat treatment . The cold sintered series included three types of pellets: those cold sintered without any liquid agent (Z3), with H 2 O (Z4), and with 5 M NaOH (Z5).…”

“…Subsequently, sintered zeolite 13X pellets (Z2) were produced by treating Z1 pellets at 700 °C in a box furnace for 4 h, following the temperature profile shown in Figure S1a, with additional details of heat treatment. 34 The cold sintered series included three types of pellets: those cold sintered without any liquid agent (Z3), with H 2 O (Z4), and with 5 M NaOH (Z5). Each liquid agent (17 wt %) was added to the starting powder and mixed homogeneously using a mortar and spatula.…”