A novel preparation method was proposed for a metal-organic framework (MOF) monolith using a simple one-pot synthesis method. A MOF tubular monolith was successfully prepared by the hydrothermal treatment for an α-Al2O3 monolith in an aqueous solution of 1,3,5-benzenetricarboxylic acid and nitric acid without the addition of a metal source. The effects of temperature and the HNO3 concentration in the synthesis solution on the crystallization behavior of MIL-96 were studied. HNO3 enhanced the dissolution of the α-Al2O3 monolith and the growth of MIL-96. The growth rate of MIL-96 was also influenced by the synthesis temperature; a synthesis temperature of over 453 K was required for crystallization. The CO2 adsorption capacity of the prepared MIL-96 monoliths was evaluated and found to be comparable to that of the well-grown MIL-96 powdery crystal. Furthermore, the MIL-96 monoliths demonstrated good stability as their adsorption properties were retained even after 2 months of storage under atmospheric conditions.
Keywords: CO2; MIL-96; adsorption; metal−organic framework; monolith.