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Silicoalumiophosphates (SAPOs) are microporous crystalline materials extensively utilized as adsorbents and catalysts. The present work utilized two strategies to synthesize nanocrystalline SAPO‐11. The first strategy involves a surfactant as a mesoporogen to reduce the crystallite size and increase the surface area for the materials synthesized at 200 °C in 2 days. In the second strategy, the synthesis temperature and time were significantly reduced to 160 °C and 3 h using propylene oxide as a pH accelerator. The reduction in the particle size and the improvement in the surface area were achieved using propyltriethoxysilane, which inhibited the growth of SAPO‐11 particles. The materials were thoroughly characterized using XRD, N2‐sorption, FTIR, pyridine‐adsorbed FTIR, electron microscopy, XPS, and NMR. The surfactant‐assisted synthesis formed a nanorod morphology with a large external and BET surface area. The low‐temperature synthesis involving silane as a growth inhibitor and propylene oxide as a pH modulator demonstrated a rectangular nanoplatelet morphology with a large surface area. The synthesis was scaled up to 10 g with no change in the experimental parameters. A synthesis strategy facilitating nuclei formation and retarding the growth of particle size will attract academia and industrial researchers to utilize these strategies for the manufacturing of zeolites of different frameworks on a large scale. [ABSTRACT FROM AUTHOR]

Mesoporous alumina (MA) with interesting morphologies of flower or three‐dimensional hierarchical spheres like nanostructures were synthesized in the absence of any template. Hydrothermal synthesis strategy was applied for synthesis of mesoporous γ‐ alumina with tunable properties like BET surface area, pore volume, pore size and superior acidic property. Over all experiments were conducted systematically using aluminum sulfate hydrolysis, precipitation, growth/nucleation. The formation of flower like structures of γ‐Al2O3 were characterized by X‐ray powder diffraction (XRD), N2physisorption, scanning electron microscope (SEM), Temperature programmed ammonia desorption (TPD) for acidity, Nuclear magnetic resonance (NMR) spectroscopy. In order to study the effect of chelating agents like urea and role of complexing agents, a series of contrast experiments were carried out. The novel synthesis methodology yielded MAs with exceptionally high surface areas, pore volumes, uniform pore size distributions and versatile acidic strengths. This present investigation provided a simple and effective approach for preparing mesoporous alumina and the different kinds of morphologies structures of alumina can be controlled precisely by choosing appropriate complexing agents and optimum quantity of precipitating agents. This approach of work not only allows us to investigate the growth mechanism of the final product, but also reduces cost and the environmental pollution effectively than other template methods. [ABSTRACT FROM AUTHOR]