Data analysis of the protection performance of Citrus reticulate and Pelargonium on the corrosion rate of mild steel in acidic solution

Abstract

Data on the protection efficiency of Citrus reticulate (CR) and Pelargonium (PG) oil distillates, and their combined admixture (CRPG) on the corrosion of mild steel in 0.5 M H2SO4 and 0.5 M HCl solution are presented. Performance of CR and PG in HCl solution are comparable and generally effective at all concentrations with optimum value of 85.94% and 89.68% at 1% and 1.5% distillate concentration. Performance of CR and PG in H2SO4 solution were significantly concentration dependent with poor protection values at 0.5% to 1.5% for CR and 0.5% to 1.25% for PG. At 1.75% CR, and 1.5% and 1.75% PG concentrations, protection efficiency of 73.09%, 96.17% and 95.46% were attained. CRPG performed effectively in H2SO4 solution with average protection value above 90% while in HCl solution CRPG performed poorly at all concentrations with performance values below 60%. Statistical data showed inhibitor concentration dominated the protection performance outputs of the distillates compared to exposure time whose effect was marginal but statistically relevant. Data from standard deviation showed the CRPG in HCl and CR in H2SO4 solution varied the least from average data values signifying stable inhibition with respect to time and concentration. 53% and 50% of CR protection efficiency data in HCl and H2SO4 solution were above the 80% effective protection value at margins of error of ± 12.62 and ± 12.65. The corresponding values for PG showed 42% and 67% are above the threshold value at ± 12% margin of error. The protection value for CRPG above the threshold value is 67% in HCl solution and 0% in H2SO4 solution at margins of error of ± 11.93% and ± 0%.