A facile, rapid, and noninvasive method for reconstructing ZnAl layered double hydroxide (LDH) is reported. ZnAl LDH series were synthesized at different Zn2+/Al3+ atomic ratio (1.5-4) via an alkali-free method and reconstructed under hydrothermal route (HTM) for the first time. Fresh Zn/Al LDHs were activated at 300°C and reconstructed under hydrothermal process. A better insight and correlation study between the physiochemical properties of reconstructed ZnAl LDH in terms of their crystallinity, surface area and basicity also will be gained here. BET surface area of rehydrated samples increased up to 355 m2/g (Zn:Al ratio 3:1). CO2-TPD probed high number of basic sites density (0.1 mmol/g).

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Several mesoporous alumina samples have been successfully prepared via simple and easy precipitation method by using inexpensive inorganic aluminium salts with ammonium acetate as precipitating agent. The aluminium acetate (Al(CH3COO)3) precipitate obtained was treated with nitric acid, acetone and ultrasonication to obtain mesoporous alumina. FESEM of the samples prepared from the treatment of nitric acid showed agglomeration of spherical nano-sized particle while TEM micrographs showed homogenous nano-sized pores in the range of 7-9 nm which agrees with data from nitrogen adsorption analysis. Al(CH3COO)3 treated with acetone followed by ultrasonic treatment exhibits narrower pore size distribution between 3.5-5.0 nm with higher surface area (198.36 m2/g) as compared to the sample without ultrasonic treatment. Acidity study of the alumina sample using pyridine adsorption indicates that the sample exhibits Lewis acidity.