Odabir pseudoreferentne elektrode za sustav unutarnje katodne zaštite

undergraduate thesis

• Title (english): Selection of pseudo-reference electrode for internal cathodic protection system
• Author: Barbara Šimanović
• Mentor: Helena Otmačić Ćurković (mentor)
• Committee member: Helena Otmačić Ćurković (predsjednik povjerenstva)
• Committee member: Igor Sutlović (član povjerenstva)
• Committee member: Suzana Sopčić (član povjerenstva)
• Granter: University of Zagreb; Faculty of Chemical Engineering and Technology; Zagreb
• Defense date and country: 2017-09-14, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Chemical Engineering; Analysis, Synthesis and Management of Chemical Processes

Abstract

Ovaj rad baziran je na problemu iz prakse gdje je došlo do korozije unutarnje stjenke čeličnih bojlera te je bilo potrebno odabrati adekvatnu katodnu zaštitu. Cilj rada bio je ispitati mogućnost primjene različitih metalnih materijala kao pseudoreferentnih elektroda u sustavima unutarnje katodne zaštite. Metali na kojima se vršilo ispitivanje su titan, nikal-krom i bakar-nikal legura. Navedenim metalima određivao se korozijski potencijal pri različitim temperaturama u trajanju od 14 dana. Na početku te na kraju mjerenja za svaki metal provedena su ispitivanja metodom elektrokemijske impedancijske spektroskopije. Odabir pseudoreferentnih elektroda temelji se na stabilnosti njihovih potencijala i pouzdanosti. Najmanje oscilacije potencijala u vremenu, kao i najmanje razlike među pojedinim uzorcima primijećene su kod Cu-Ni legure dok su razlike najveće kod titana. Analizom standardne devijacije, odnosno usporedbom rasipanja vrijednosti potencijala utvrđeno je kako je uporaba legure Cu-Ni kao pseudoreferentne elektrode najpouzdanija, dok je najmanje pouzdana uporaba titana. Elektrokemijskom impedancijskom spektroskopijom dobiven je uvid u svojstva otpornosti ispitivanih metala. Za razliku od titana i legure Cr-Ni, kod legure Cu-Ni ne dolazi do nastanka pasivnog sloja pa ova legura pokazuje najmanju korozijsku otpornost.

Abstract (english)

This work is based on the problem from practice, where the corrosion of inner walls of steel boilers occurred and it was required to choose the adequate cathodic protection. The aim of the work was to examine the possibility of applying different metal materials as pseudo-reference electrodes in internal cathodic protection systems. The tested metals were titanium, nickel-chromium and copper-nickel alloy. The corrosion potential of these metals were examined at different temperatures during the period of 14 days. At the beginning and at the end of study, the electrochemical impedance spectroscopy was conducted. The selection of pseudo-reference electrodes is based on the stability of their potentials and obtained reliability. The slightest potential oscillations, as well as the lowest differences between the individual samples, were observed in Cu-Ni alloys, while the differences were highest in titanium. Based on the analysis of dispersion of measured potential values, it was established that the use of Cu-Ni alloys as a pseudo-reference electrode is the most reliable, while the use of titanium is the least reliable. The electrochemical impedance spectroscopy provided insight into the resistance properties of the tested metals. Unlike titanium and Cr-Ni alloy, Cu-Ni alloy does not exhibit any passivity properties and has proved to be the most prone to corrosion.

• Keywords: korozija; katodna zaštita; korozijski potencijal; elektrokemijska impedancijska spektroskopija
• Keywords (english): corrosion; cathodic protection; corrosion potential; electrochemical impedance spectroscopy
• Language: croatian
• URN:NBN: urn:nbn:hr:149:773032
• Study programme: Title: Materials Science and Engineering - Undergraduate study; Study programme type: university; Study level: undergraduate; Academic / professional title: sveučilišni/a prvostupnik/ prvostupnica (baccalaureus/baccalaurea) inženjer/inženjerka kemijskog inženjerstva (sveučilišni/a prvostupnik/ prvostupnica (baccalaureus/baccalaurea) inženjer/inženjerka kemijskog inženjerstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2021-03-11 13:08:56