MCM-41 carbon replica using rice husk as an alternative in the use of green hydrogen

JULIANA M. JUÁREZ; JHOAN F. TÉLLEZ; E. LAURA MOYANO; MARCOS B. GÓMEZ COSTA

París

Conferencia; CCM-2023 Hybrid Conference; 2023

CCM-2023 Hybrid Conference

In this work, the synthesis and characterization of silicon mesoporous nanostructured materials and their carbon replica will be carried out using eco-friendly silicon sources such as rice husk residues, to be used in the adsorption of hydrogen as an alternative in the use of green hydrogen. To obtain said nanostructured materials a synthesis technique was developed with this new eco-friendly and low-cost alternative.In this research, the silicon mesoporous material MCM-41 was synthesized using rice husk as a silicon source. To obtain the precursor SiO2, the rice husk was washed several times with distilled water to remove adhering dirt and impurities, then it was dried at 100 ºC and a treatment with 3M HCl was carried out to remove metallic impurities. After washing and drying, the shell obtained was calcined at 700 ºC for 6 hours. The synthesis of the mesoporous siliceous material MCM-41 was carried out by hydrothermal synthesis using cetyltrimethylammonium bromide (CTAB) as surfactant. The replica of the MCM-41 mesoporous material was obtained using the nanocasting technique, with sucrose as carbon source and MCM-41 as template.The materials successfully synthesized were characterized by X-ray diffraction, SEM, textural properties, and transmission electron microscopy analyses. The siliceous material MCM-41 has a BET surface of 710 m2/g and an average (BJH) pore diameter of 3 nm. Regarding the carbon replica of said MCM-41 material, the BET area is 860 m2/g and presents an average (BJH) pore diameter of 3.5 nm.The obtained replica of MCM-41 significantly improved H2 storage behavior compared to CMK-3 type nanostructured carbon (2.4% by weight at -196,15 ºC and 10 bar). The synthesized material shows promise in absorbing hydrogen by weak binding forces (physisorption).