Preparation of Ordered Mesoporous Alumina Particles via Simple Precipitation Method

Abstract

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.

Effect of concentration sulfuric acid on alumina extraction from napa soil

“…The wavenumber 4000-1250 cm -1 shows the vibrational absorption bands of -OH groups that bind octahedral Al atoms; vibration of Al-O bond elongation appears in the wavenumber region 850-650 cm -1, which has a symmetrical range [19]. Based on some literature, it states that the peak of vibration absorption and bending of Al-O is found in the wavenumber area of 738 cm-1 and 620 cm -1 [20]. In other literature, the rise of IR absorption in the 775 cm-1 and 590 cm-1 wavenumber is the vibration and bending of Al-O.…”

The Physicochemical Analysis of Bayerite Al(OH)3 → γ-Al2O3 Transformation

“…Currently, the most common route is the thermal decomposition of aluminum hydroxides and oxyhydroxides. Hydroxides are usually obtained by precipitation [14][15][16][17][18][19][20][21]. There were used various precipitating agents, such as NaOH and n-butylamine [15], ammonium acetate [16], ammonium carbonate [17], ammonium bicarbonate [18], soda [19], ammonia [20], sodium carbonate [21].…”