Obstojnost protikorozijskih hidrofobnih prevlek pri povišani temperaturi

diplomsko delo univerzitetnega študijskega programa I. stopnje

Julij Lozinšek (Author), Regina Fuchs-Godec (Mentor), Matjaž Finšgar (Co-mentor)

Abstract

Predhodno obdelane jeklene podložke smo potopili v stearinsko kislino z namenom, da bi preverili korozijske inhibicijske lastnosti. Vzorce smo zbrusili, očistili in jih zaščitili s slojem stearinske kisline. Sloj smo tvorili s potopitveno metodo. Korozivno okolje je bila razredčena klorovodikova kislina. Pri poskusih smo spreminjali temperaturo korozivnega okolja v intervalu od 25 °C do 80 °C. Spreminjali smo še čas potopitve vzorcev v stearinski kislini, in sicer smo izvajali 3-urno in 24-urno potopitev. Glavni konstantni parametri so bili koncentracija stearinske kisline, koncentracija klorovodikove kisline in čas potopitve v korozivnem mediju. Pri poskusih smo zasledili določeno odstopanje meritev pri višjih temperaturah, na kar so vplivale nekatere spremenljivke, ki jih nismo predvideli. Te so: – predzgodovina vzorcev; - neenaka kemijska sestava vzorcev; - nepopolnost zaščitnega sloja; - mehanske obremenitve pri izdelavi vzorcev; - povečana kontaktna površina vzorcev. Vse te spremenljivke so predvidoma vplivale na vrednost inhibicijske učinkovitosti. Najvišjo inhibicijo smo pri 3-urni in 24-urni potopitvi v stearinski kislini dobili pri najnižji temperaturi 25 °C. Inhibicija je pri 3-urni in 24-urni potopitvi padala od temperature 25 °C do 40 °C. Pri 24-urni potopitvi smo dosegli višje inhibicije kot pri 3-urni. Nepričakovano se je inhibicijska učinkovitost pri 3-urni in 24-urni potopitvi v območju med 40 °C in 70 °C močno povečala. Eksperimentalno delo prikazuje možnost uporabe nasičenih maščobnih kislin v namene inhibicije korozije kovinskih materialov. Stearinska kislina je nedvomno primerna, saj je ekonomsko ugodna, je dostopna, okolju prijazna in lahko odstranljiva s površine materiala. Izstopajoča slaba lastnost je mehanska neobstojnost. Vsekakor so potrebne nadaljnje raziskave, da bi bolje razumeli vse parametre, ki vplivajo na njene inhibicijske lastnosti. Nadaljnje raziskave bi zagotovo pripomogle k izboljšavam inhibicijskih lastnosti te maščobne kisline.

Keywords

korozijski inhibitorji;protikorozijski surfaktanti;stearinska kislina;korozija;organski inhibitorji;diplomske naloge;

Data

Language:	Slovenian
Year of publishing:	2016
Typology:	2.11 - Undergraduate Thesis
Organization:	UM FKKT - Faculty of Chemistry and Chemical Engineering
Publisher:	[J. Lozinšek]
UDC:	620.193:667.648.2(043.2)
COBISS:	20305686
Views:	1044
Downloads:	113
Average score:	0 (0 votes)
Metadata:

Other data

Secondary language:	English
Secondary title:	Stability of anti-corrosion hydrophobic surfactants at elevated temperatures
Secondary abstract:	Stearic acid was applied on pretreated steel washers to investigate corrosion inhibition properties. Specimen were grinded, cleaned and protected with a thin layer of stearic acid. Layer was formed with immersion in a solution of stearic acid. The corrosive environment was diluted hydrochloric acid. Temperature of corrosive environment was adjusted in range from 25 °C to 80 °C. Time of adsorption of stearic acid on specimen was also adjusted. We conducted two time variants, shorter 3-hour and longer 24-hour immersion. Main constant parameters were concentration of stearic acid, hydrochloric acid and time of corrosion exposure. Deviation of measurements at higher temperatures was observed during experimental period, this is suspected due to: - prehistory of specimen; - uneven chemical composition of specimen; - imperfections of protective layer; - mechanical stress of manufacture; - increased contact area. Above listed parameters influenced inhibition efficiency. Higher inhibition efficiency was achieved with longer 24-hour immersion. Inhibition efficiency was decreasing from 25 °C to 40 °C and increasing from 40 °C to 70 °C in both 3-hour and 24-hour immersion. This experimental work shows possibility of corrosion protection with saturated fatty acids. Stearic acid is undoubtedly good candidate because it is cheap, accessible, environmentfriendly and easy to remove from surface of the metal. However, further more detailed work is needed to be done to better understand all parameters which affect inhibition properties of stearic acid. Further studies would surely advance inhibition properties and potential use of this fatty acid.
Secondary keywords:	corrosion inhibitors;anti-corrosion surfactants;stearic acid;corrosion control;organic surfactants;
Type (COBISS):	Bachelor thesis/paper
Thesis comment:	Univ. v Mariboru, Fak. za kemijo in kemijsko tehnologijo
Pages:	VIII, 35 str.
ID:	9154322