Ultrasonic assisted synthesis of Bikitaite zeolite: A potential material for hydrogen storage application

Abstract

Li containing Bikitaite zeolite has been synthesized by an ultrasound-assisted method and used as a potential material for hydrogen storage application. The Sonication energy was varied from 150W to 250W and irradiation time from 3h to 6h. The Bikitaite nanoparticles were characterized by X-ray diffraction (XRD), infrared (IR) spectral analysis, and field-emission scanning electron microscopy (FESEM) thermo-gravimetrical analysis and differential thermal analysis (TGA, DTA). XRD and IR results showed that phase pure, nano crystalline Bikitaite zeolites were started forming after 3h irradiation and 72h of aging with a sonication energy of 150W and nano crystalline Bikitaite zeolite with prominent peaks were obtained after 6h irradiation of 250W sonic energy. The Brunauer-Emmett-Teller (BET) surface area of the powder by N adsorption-desorption measurements was found to be 209m/g. The TEM micrograph and elemental analysis showed that desired atomic ratio of the zeolite was obtained after 6h irradiation. For comparison, sonochemical method, followed by the hydrothermal method, with same initial sol composition was studied. The effect of ultrasonic energy and irradiation time showed that with increasing sonication energy, and sonication time phase formation was almost completed. The FESEM images revealed that 50nm zeolite crystals were formed at room temperature. However, agglomerated particles having woollen ball like structure was obtained by sonochemical method followed by hydrothermal treatment at 100°C for 24h. The hydrogen adsorption capacity of Bikitaite zeolite with different Li content, has been investigated. Experimental results indicated that the hydrogen adsorption capacities were dominantly related to their surface areas as well as total pore volume of the zeolite. The hydrogen adsorption capacity of 143.2c.c/g was obtained at 77K and ambient pressure of (0.11MPa) for the Bikitaite zeolite with 100% Li, which was higher than the reported values for other zeolites. To the best of our knowledge, there is no report on the synthesis of a Bikitaite zeolite by sonochemical method for H storage.

Synthesis of high surface area mesoporous silica SBA‐15 for hydrogen storage application

“…Although from Table , it is seen that P5 powder has lower pore wall thickness, the rupturing of mesopore structure upon the application of high sonication energy makes it a very low surface area powder. Figure shows the comparison of H 2 adsorption capacity of SBA‐15 powders synthesized in this work with other reported values of hydrogen adsorption by other different materials . It is clear that the present result of hydrogen adsorption capacity of the high surface area powder P4 is higher than the reported value till date.…”

Zeolite RHO Synthesis Accelerated by Ultrasonic Irradiation Treatment

“…10.43–18.29% loss up to 200 °C may be attributed to the desorption of physically adsorbed water 34 . With further heating up from 200–500 °C, the weight loss of the synthesized samples of about 0.19–2.42% weight loss are due to the decomposition and removal of hydroxyl group in the as-synthesized zeolite samples 39 . The weight loss of the synthesized samples in current study are comparable with the work reported by Liu et al .…”

Zeolites: An Emerging Material for Gas Storage and Separation Applications

“…In the case of Bikitaite zeolite, the molar composition of the sol used for the synthesis was 10 Li 2 O:0.5 Al 2 O 3 :2.5 SiO 2 :600 H 2 O [56]. Like the previous protocol, two reactant mixtures were prepared respectively by suspending the measured amount of colloidal silica and lithium hydroxide in deionized water (DI water) in a glass beaker (mixture 1).…”

“…This method has potential advantages in terms of achieved preferential orientation control of membrane microstructure and higher reproducibility if compared with the in situ synthesis method [39]. Extensive studies have been performed aiming at investigating potential of zeolites and derived membranes for gas separation [40][41][42][43][44][45][46][47][48][49][50][51][52][53][54][55][56]. Specific zeolites have a high capacity and selectivity for the gases of interest, leading to compact and efficient separation/storage systems.…”