Na 2 SO 4 , pH=3). Dobijeni rezultati ukazuju na dobru inhibitorsku efikasnost ispitivanog derivata UVODBakar i njegove legure spadaju u važan konstrukcioni materijal koji je često izložen kiseloj sredini prilikom prečišćavanja, pri otklanjanju korozionih proizvoda sa prenosnika toplote, elektrohemijskog glačanja, itd. Najčešće korišćena kiselina u ovim procesima je sumporna kiselina, u čijem prisustvu može doći do korozije bakra, pošto je formiranje pasivnog oksidnog sloja na površini metala onemogućeno [1]. Zaštita bakra u kiseloj sredini se najčešće vrši primenom korozionih inhibitora. Veliki broj molekula je do sada ispitivan kao potencijalni inhibitor korozije bakra. Na osnovu objavljenih rezultata uočljivo je da dobre inhibitorske osobine imaju organski molekuli koji u svojoj strukturi sadrže heteroatome azota, sumpora ili kiseonika [2][3][4][5][6][7][8]. Najveći broj njih ispoljava dobru inhibitorsku efikasnost u neutralnoj sredini, dok je broj jedinjenja sa dobrim zaštitinim osobinama u kiseloj sredini limitiran [9][10][11][12][13].Derivati tiazola spadaju u grupu jedinjenja koja se pokazala kao dobar inhibitor korozije bakra u kiselo-sulfatnoj sredini. Ovi organski molekuli svoje inhibitorsko dejstvo na koroziju pretežno ispoljavaju adsorpcijom na metalnu površinu usled čega se stepen korozije metala smanjuje [14][15].

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Two methods are proposed for dry-wet formation of membranes from SCA for ultrafiltration of cheese whey: dry formation followed by modification in aqueous medium and spontaneous gelation on a calender followed by modification in aqueous medium, which significantly differ in the solvent evaporation rate (12 h and 3-5 min). It was shown that the solvent evaporation rate affects formation of the pore structure of the membranes. In formation with the spontaneous gelation method on a calender, membranes with a less developed pore structure and better permeability for water and cheese whey are obtained in comparison to membranes formed by the dry method. The pore structure of the membranes can be regulated with NaHCO 3 filler. Membranes from 5-7% solutions of SA at a 3-4 wt. % NaHCO 3 content are the most efficient.The use of ultrafiltration units for processing dairy products has led to important savings of raw material and power resources and has expanded the assortment of dairy products and increased their biological value [1]. The efficiency and selectivity of ultrafiltration are determined by the structure of the membranes and size and position of the pores in the membrane.Membranes for ultrafiltration are usually manufactured by dry and dry-wet methods [2]. Phase separation takes place as a result of evaporation of the volatile solvent from the polymer solution and this leads to formation of a polymer phase in the form of a gel backbone and cells of a low-molecular-weight phase in the form of a system of through capillaries filled with liquid in the stage of formation that permeate the gel. Adhesion of the polymer to the support prevents free contraction of the polymer phase in evaporation. As a result of the competing effect of oppositely directed forces, partial rupture of the polymer backbone and formation of the membrane pore structure take place. Porous membranes have a system of through pores which ensure phase permeability of the components of the separated systems. The pores in the membranes can be isolated from each other or form a labyrinthal system of interconnected channels. Rigidity of the structure of the filter, which guarantees retention of particles of the separated component, is an important requirement imposed on membranes. It is believed [2] that the structure of the pores in membranes is a function of the solvent evaporation rate.To study the effect of the solvent evaporation rate on the performance properties of ultrafiltration membranes made of secondary cellulose acetate (SCA), we used modified methods of dry-wet formation of membranes: dry formation (coating method) followed by modification in aqueous medium and spontaneous gelation on a calender, also followed by modification in aqueous medium. The methods used differ significantly with respect to the solvent evaporation rate (12 h and 5 min).In dry formation of membranes, a solution of SCA was placed in special cylindrical molds whose ends were ground to fit the glass support. Acetone was evaporated over 12 h at 20°C in a fume chamber. ...