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Cilj ovog rada bio je elektrokemijskim putem ukloniti bakar iz modelne otopine bakar(II)-sulfata pomoću elektrokemijskog protočnog reaktora. Korišten je elektrokemijski reaktor napravljen od pleksiglasa dimenzija 3 cm x 3 cm x 10 cm. Prilikom odabira materijala za izradu elektroda ispitana su svojstva različitih materijala metodom cikličke voltametrije i metodom rotirajuće disk elektrode. Kao katodni materijal izabran je čelik, dok je kao anodni materijal izabrano olovo. Elektroliza je provedena pri konstantom naponu od 2,5 V kod sedam različitih brzina protoka tijekom dva sata. Određeni su koeficijenti prijenosa mase, km za svaku brzinu protoka i oni su se kretali u granicama od 0,458*10^-3 cm s^-1 do 2,466*10^-3 cm s^-1. Osim pomoću km prijenos mase u reaktoru okarakteriziran je i preko bezdimenzijskih veličina (Sh, Re i Sc) uz pomoć kojih je određena korelacijska jednadžba. Ispitivanja su pokazala da djelotvornost uklanjanja bakra pri naponu od 2,5 V raste s porastom brzine protoka i to u rasponu od 38,42 % do 92,92 %. Specifična potrošnja energije izražena po volumenu tretirane otopine raste s porastom brzine protoka u rasponu od 2,3 W h L^-1 do 6,5 W h L^-1 dok specifična potrošnja energije izražena po masi uklonjenog bakra pada s porastom brzine protoka u rasponu od 4804,96 W h kg^-1 do 2596,92 W h kg^-1. The goal of this work was to use an electrochemical process to remove copper from a model solution of copper(II)-sulphate by using of flow through electrochemical reactor. The reactor was made of acrylic glass with dimensions 3 cm x 3 cm x 10 cm. A different materials were tested by using cyclic voltammetry method and rotating disc electrode in order to select suitable electrode materials. A steel has been selected as the cathode material and a lead has been selected as the anode material. The performance of the electrochemical reactor was investigated by using different flow rates during two hours at 2.5 V. The mass transport coefficient, km, has been determined for each flow rate and its values were found to be between 0.458*10^-3 cm s^-1 and 2.466*10^-3 cm s^-1. Additionally, mass transport phenomena were analysed by using dimensionless numbers (Sh, Re and Sc) that were fitted to the equation: Sh = aRe^b Sc^(1/2). The experiments carried out in this work has shown that the efficiency of copper removal increases from 38.42 % up to 92.92 % by increasing the flow rate. The specific energy consumption per volume of treated water increases from 2.4 W h L^-1 up to 6.5 W h L^-1, while specific energy consumption per mass of removed copper decreases from 4804.96 W h kg^-1 up to 2596.92 W h kg^-1 by increasing the flow rate.

Svrha ovog rada bila je ukloniti bakar iz modelne otopine bakrovih iona elektrokemijskim putem pri čemu je korišten protočni reaktor sa pločastim elektrodama. Elektrodni materijali je odabran na način da su provedena ispitivanja metodama cikličke voltametrije, kronoamperometrije, kronopotenciometrije te rotirajuće disk elektrode uz korištenje troelektrodnog sustava. Nakon ispitivanja kao najbolji katodni materijal se pokazala platina, zlato, olovo i čelik. S obzirom na visoku cijenu platine i zlata, kao katodni materijal izabran je čelik. Olovo je izabrano kao anodni materijal jer se u području pozitivnih potencijala na površini olova formira stabilan sloj PbO2 koji katalizira reakciju razvijanja kisika. Nakon odabira elektrodnog materijala izradio se elektrokemijski reaktor te je provedena elektroliza kod tri različite vrijednosti napona i tri različita protoka elektrolita. Pri tome je određen koeficijent prijenosa mase koji je varirao od 1,887x10^-3 cm s^-1 do 7,183 x10^-3 cm s^-1 . Određene su i bezdimenzijske veličine (Sh, Re i Sc) koje su stavljene u odnos kako bi se okarakterizirao prijenos mase u reaktoru. Pri tome su kod različitih napona dobiveni različiti parametri jednadžbe Sh=aRe^bSc^1/3 . Postotak uklonjenog bakra veći je od 96% za sve slučajeve, osim za najmanju brzinu protoka uz 2,5 V, pri čemu djelotvornost uklanjanja bakra raste s porastom napona i protoka. Specifična potrošnja energije elektrolize izražena po masi uklonjenog bakra raste s porastom napona te pada s porastom brzine protoka, a kretala se u granicama od 4937 W h kg^-1 do 10.281 W h kg^-1. The aim of this work was to remove copper from a model solution of copper ions using a flow through electrochemical reactor with parallel plate electrodes. Different materials were tested by using cyclic voltammetry, chronoamperometry, chronopotentiometry and rotating disc electrode with a three-electrode system. Platinum, gold, led and steel have shown the best properties in order to be used as cathode material. Considering the high price of platinum and gold, chosen cathode material was steel. Led was chosen as anode material due to the formation of PbO2 in positive potential range and catalytic activity for oxygen evolution reaction. After choosing the appropriate electrode materials, the reactor was assembled and the performance of the electrochemical reactor was investigated at three different voltage values and three different flow rates. In this experiment mass transfer coefficient was determined to be between 1,887x10^-3 cm s^-1 and 7,183 x10^-3 cm s^-1. Dimensionless numbers (Sh, Re and Sc) were correlated to characterize mass transport properties of the electrochemical reactor and they were fitted to the equation Sh=aRe^bSc^1/3. Removal efficiency of copper was higher than 96% for all experiments with the exception of lowest flow speed and voltage of 2.5 V. The removal efficiency increased with increase of voltage and flow rate. Specific energy consumption decreased with the voltage and flow rate decrease in the range from 4937 W h kg^-1 to 10 281 W h kg^-1.