Feasibility and corrosion inhibition efficacy of zeolite-supported lauric acid imidazoline as corrosion inhibitor in cementitious mortar. (30th July 2020)

• Record Type: Journal Article
• Authors: Xu, Weiting; Wei, Jiangxiong; Yang, Zhenguo; Xu, Peng; Yu, Qijun
• Is Part Of: Construction & building materials. Volume 250(2020)
• Publication Date: 2020-07-30
• Subjects: LAI Lauric acid imidazoline -- Ca2+-zeolite Ca2+-exchanged zeolite -- ZSLAI Natural zeolite supported lauric acid imidazoline -- Ca2+-ZSLAI Ca2+-zeolite supported lauric acid imidazoline -- OCP Open circuit potential -- EIS Electrochemical impedance spectroscopy -- DPP Dynamic potential polarization -- SEM Scanning electron microscopy -- XRD X-ray diffraction -- FTIR Fourier transform infrared spectroscopy -- R Reference mortar -- L1 Mortar with 0.5% of cement replaced by LAI by mass -- L2 Mortar with 1% of cement replaced by LAI by mass -- Z1 Mortar with 3% of cement replaced by Ca2+-zeolite by mass -- Z2 Mortar with 6% of cement replaced by Ca2+-zeolite by mass -- ZL1 Mortar with 3% of cement replaced by Ca2+-zeolite saturatedly supported LAI -- ZL2 Mortar with 6% of cement replaced by Ca2+-zeolite saturatedly supported LAI; Steel -- Organic corrosion inhibitor -- Lauric acid imidazoline -- Loading -- Zeolite -- Steel reinforced mortar -- Electrochemical property; Building materials -- Periodicals; 624.18
• DOI: 10.1016/j.conbuildmat.2020.118861
• Languages: English
• ISSNs: 0950-0618

Abstract

Highlights: A novel corrosion inhibitor Ca 2+ -ZSLAI was synthesized. Ca 2+ -zeolite loading LAI with 1% by mass of cement presented best corrosion resistance efficacy. Addition of Ca 2+ -ZSLAI increased compressive strength and lowered porosity of mortar. Using of Ca 2+ -zeolite as additive improved the corrosion resistance of the embedded steel. Abstract: A zeolite supported organic corrosion inhibitor with high loading efficiency was obtained by loading a synthesized lauric acid imidazoline (LAI) in the Ca 2+ -exchanged zeolite (Ca 2+ -zeolite) framework. The influences of the as-prepared Ca 2+ -zeolite supported LAI (Ca 2+ -ZSLAI) as an admixture in porosity and compressive strength of the resulting cement mortar were examined. The protective effect of Ca 2+ -ZSLAI against steel corrosion of steel-mortar immersed in NaCl solution was discussed upon. The properties of the steel reinforced mortar incorporating Ca 2+ -ZSLAI was compared with the reference mortar specimen without corrosion inhibitor and the specimen solely with LAI or Ca 2+ -zeolite. The steel corrosion resistance performance of Ca 2+ -ZSLAI was revealed by electrochemical testing on steel reinforced mortar during the chloride ions accelerated corrosion test. Experimental results revealed that mortar with 6% of cement replaced by Ca 2+ -zeolite saturatedly supported LAI as corrosion inhibition additive presented 14% higher compressive strength and 23% lower total porosity compared to the reference mortar. Besides, such dose of inhibitor could retain 92% corrosion inhibition efficiency of the embedded steel after 142 immersion days. The excellent corrosion resistance efficacy of Ca 2+ -ZSLAI was ascribed to the chloride "binding capacity" of the densified mortar substrate improved by the filling and pozzolanic effect of Ca 2+ -zeolite and the chloride "barrier capacity" of the protective interfacial film deposited by the LAI released from the Ca 2+ -zeolite carrier.