Sulfuric Acid and Ammonium Sulfate Leaching of Alumina from Lampang Clay

Abstract

Abstract:The rapid development of the global alumina industry has led to a considerable increase in the production alumina and processing of alumina from non-bauxitic sources. Lampang clays comprise various minerals that contain about 22.70 wt% of extractable alumina. Local clay was ground, activated by calcination and treated with sulfuric acid to extract alumina. In the activation step, the effects of temperature and time on the extraction of alumina and iron were investigated. The leaching experiments were performed on clay samples with particle sizes less than 200 mesh. The samples were calcined at different temperatures, ranging from 450 o C to 1050 o C, and for different periods, ranging from 30 to 150 min. The optimum conditions for the extraction of alumina from Lampang clay include grinding the clay to pass through a 200 mesh sieve, calcining the ground clay at 750 o C for 30 min, extracting the alumina from the calcined clay by leaching with 3M sulfuric acid, and using an acid to clay ratio of 80 wt% at 100 o C for 120 min. An aluminum dissolution efficiency of 95.1 % was achieved under the conditions that resulted in the maximum dissolution efficiency of iron (26.6 %).

Activation of Jordanian Bentonite by Hydrochloric Acid and Its Potential for Olive Mill Wastewater Enhanced Treatment

“…Therefore, the higher temperature generates a greater driving force for phenolic compounds to be fixed on the adsorbent. The same trend has been reported by the others [52].…”

Kil Minerallerinden Alümina Üretimi: Güncel Değerlendirmeler

“…Alümina kazanım yüzdesinin kalsinasyon sıcaklığı, liç sıcaklığı, asit derişimi ve karıştırma hızıyla doğru orantılı, ancak katı/çözelti oranıyla ters orantılı olduğu bulunmuştur. Numluk ve Chaisena [32], %22,7 Al2O3 içeren killerden 750 °C sıcaklıkta kalsine edildikten sonra 3 M sülfürik asit çözeltisinde 100 °C sıcaklıkta 2 saat liç işlemi sonucunda alümina kazanımının %95,1 olduğunu rapor etmişlerdir. Birinci vd.…”

Effect of pure Aluminum in Reduction of Silica from Sediments in Iraqi-Tigris

“…Table (10) shows the purification of silicon produced an effect of sulfuric acid on dissolving impurities in the samples and figure (4) shows the EDX spectra of the silicon powder. Angus L. Daniels [16] and Paween Numluk [17] explained that the aluminum oxide (alumina) react with sulfuric acid at different concentration (3-5)M and forming aluminum sulfate according to following equation (5) at 100 ˚C for 4 hrs, The efficiency of silicon extracted from sediments of Tigris river is greater than (88%). The SEM micrograph of the silicon powder as shown in Fig.…”