ZEOLITES

ZEOLITES, aluminosilicates of general formula Me_x/n[Al_xSi_yO_2(x+y)]*zH₂O (where Me – metal, n – the phase of its oxidation, x – the number of aluminum atoms, y – of silicon atoms, z – of water molecules). White, colourless and transparent, rarely reddish and greenish crystals from several cm to microns of any syngonies. Large crystals and druses of natural Z. – collection material. In the republic, Z. occur in the above‑ore strata of Sibaiskoye and Yubileynoye, Podolsk Copper‑Culphide deposits, Tuzbekskoye Manifestation in the Kizilo-Urtazymskaya Syncline; in the pelitic part of the Paleogenic gaizes and tripolis in the Tanalykskaya Depression. In 1951, the production of synthetic zeolite‑containing catalyst was launched at the Ufa Refinery. In 1967, for the first time in the country, Salavatnefteorgsintez (ref. Gazprom Neftekhim Salavat) launched the serial production of NaA, NaX brands Z. made of silicate blocks, aluminum oxide hydrate and clay; in 1970s the production of zeolite‑filled catalysts of the AShNTs type began, in 1980s – of Tseokar type. In 1985, the Ishimbay Specialized Chemical Plant launched the serial production of NaA, NaX, CaA brands Z., zeolite‑containing adsorbents and catalysts; since 1990s – grades KA, CaX, the granular zeolite‑containing component of synthetic detergents. In late 1990s, the Medical Ecological Center of the Bashkir State Medical Administration (Ufa) developed Litosorb and Litovit preparations made of Z. The main consumers of Z. are the enterprises of the Fuel and Energy Industry. Z. of NaA‑Y brand is used in power industry for drying transformer oils, NaX‑K – by OAO Sibkriotechnika (Omsk), Kriogenmash (Balashikha), NaA‑2kt – by the manufacturers of refrigeration equipment.