Magyar Aluminiumipari Troszt

Magyar Aluminiumipari Troeszt

Bela Kokeny

Jozsef Matyasi

Laszlo Zsembery

Gyorgy Kaptay

Jozsef T Toth

Imre Penzes

Sandor Nemeth

Maria Toth Nee Homostrei

Process for the preparation of alkali-poor .alpha.-alumina for ceramic purposes. Technical grade aluminum hydroxide is activated and calcinated in the presence of a mineralizing mixture comprising halides and boron compounds. The process further comprises activating aluminum hydroxide at a temperature of 500-600 degrees C., washing the activated product with alkali-free water containing calcium ions and having a conductivity not exceeding 70 .mu.S/cm until the alkali content expressed in Na.sub.2 O becomes lower than 0.15% by weight, adding 0.4-0.7% by weight of a mineralizing mixture to the washed product, and calcinating the same at a temperature of 1200-1350 degrees C.

Process for the preparation of alkali-poor .alpha.-alumina for ceramic

The invention relates to a process for preparing alumina being suitable for layer chromatography. The alumina suitable for layer chromatography is prepared in accordance with the invention in such a manner that an aluminium trinydroxyde containing 34 to 37% by weight of bayerite, 3 to 5% by weight of pseudoboehmite and 60 to 62% by weight of amorphous aluminium trihydroxide is heated at 300.degree. C. to 400.degree. C. for 2 to 4 hours. The activated alumina thus produced is snow-white, has a large specific surface and its average grain size is within the range between 8 and 20 .mu.m. The product complies with the requirements of layer chromatographical technique.

Process for preparing alumina being suitable for layer chromatography

Growing community of inventors

Almasfuzito, Hungary

Bela Kokeny