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1. Introduction
Low-alloyed steels form major materials in the manufacture of live and reheat steam pipelines (Golanski et al., 2016), steam generators, economizer assemblies, super heater, re-heaters (Reddy et al., 2014), pressure vessels and piping (Perez et al., 2011) and boilers (Huijbregt and Leferink, 2006) which find applications in petrochemical, process, marine and power industries to mention but a few. De-scaling of facilities of this sort is usually carried out to improve service performances. A way of removing scales from boiler tubes and pipes is by using acid solutions (Tahir and Saleem, 2007) and the most used mineral acids are HCl and H2SO4 (Ikpi and Abeng, 2017). Consequently, low alloyed steel materials are exposed to eventual acidic attack. Protection of metals is pertinent as these acids cause serious degradation resulting from oxidation of the alloy. Inhibitors are additions to acids for the purpose of subduing degradation rate of metals subjected to the corrosive environment (Gerengi et al., 2020). Numerous researches have been conducted on the use of different types of synthetic materials as corrosion inhibitors (Abbasov et al., 2013; Durowaye et al., 2014; Ikpi and Abeng, 2017; Abbasov et al., 2015), but this class of inhibitors are not without ecological footprint as their by-products are toxic and non-degradable. Based on this reality, a paradigm shift emerged with focus on organic and naturally occurring substances for corrosion inhibition. Some typical green/organic corrosion inhibitory materials researched earlier (Fouda et al., 2015; Nazari et al., 2017; Olasehinde, 2018; Ituen and Udo, 2018; Ugi et al., 2018; Dehghani et al., 2019; Asadi et al., 2019) exhibited features of mixed inhibitors with physisorption process mechanism prevalence. Bhola et al. (2014) found that Neem extract inhibited biologically influenced corrosion of API 5 L graded X80 steel with a more noble shift in open circuit potentials. All eight plants extracts investigated by Al-Otaibi et al. (2014) behaved as mixed inhibitors while Ajeigbe et al. (2017) reported that oil from alpinia galanga plant was adsorbed on mild steel in HCl via physisorption. Mokhtari et al. (2014) examined oil from Jatropha curcas, and it was established as a mixed corrosion inhibitor on carbon steel in 1 M HCl with activation...