Investigation and evaluation of neem leaves extract as a green inhibitor for corrosion behavior of mild steel: An experimental study

Abstract

<jats:p> It is a well-established fact that corrosion of mild steels occurs in pipelines, storage tanks, oil reservoirs, boilers, and petrochemicals industries. Green inhibitors are economical, non-toxic and eco-friendly, and forming barrier type layer of organic compounds over metallic materials. In this paper, weight loss, electrochemical measurements containing potential measurements, potentiodynamic polarization and impedance spectroscopy were applied to inspect the neem leaves extract inhibition efficiency and corrosion phenomenon under three conditions (X<jats:sub>1</jats:sub>, X<jats:sub>2</jats:sub> and X<jats:sub>3</jats:sub>) in 1.0 M HCl medium. The characterization technique including scanning electron microscopy coupled with energy dispersive spectroscopy was conducted to scrutinize the elemental analysis, corrosive pitting and morphology of corrosion products of mild steel immersed in 1.0 M HCl medium with and without neem leaves extract concentration. The corrosion inhibition efficiency of neem leaves extract increased with increasing concentration and conditioning time. By increasing the conditioning time from 0.08 h to 72 h, the corrosion inhibition efficiency of neem leaves extract was increased from 75% to 97%. The neem leaves extract corrosion inhibitor works quite effectively only for 24 h, thereafter its efficiency drastically decreases. For 24 h, neem leaves extract prevented 80–90% corrosion attack but when steel immersion time was increased to 48 h and 72 h, its efficiency decreased from 83% to 65% and 52% to 42%, respectively. </jats:p>

Corrosion inhibition effects of organic compounds on carbon steel research progress: a visualization analysis based on CiteSpace

“…Natural plants contain a variety of organic compounds with anti-corrosion properties. These compounds are considered ideal raw materials for the preparation of green, effective and low-cost organic corrosion inhibitors [78,79]. Therefore, researching how to extract effective organic compounds from natural plants and turn them into organic corrosion inhibitors has not only high scientific value but also significant practical applications [80,81].…”

The inhibition of mild steel corrosion by papaya and neem extracts

“…The highest inhibition efficiency of 93.24% was reported whilst the adsorption behaviour of the Azadirachta indica extracts agreed with the Temkin and Langmuir adsorption isotherm models. In a related study, Abro et al [44] employed weight loss, electropotential measurements, potentiodynamic polarization and impedance spectroscopy methods to investigate the corrosion inhibition of Azadirachta indica leaves extract in 1.0M HCl solution. The inhibition efficiency of Azadirachta indica leaf extract was observed to increase with exposure time.…”

Corrosion resistance and metallurgical behaviour of CMT welded Al-LCS dissimilar butt joint exposed in simulated industrial environment

“…At the end of the test period, the reaction was stopped, specimens were taken out (Figure 1(h)), corrosion product was cleaned and reweighed to calculate the weight loss (W 2 gms). The amount of metal loss was calculated from the weight difference, and the corrosion rate was expressed in millimetre per year (mmpy) using the following formulae 21 where…”

“…18 Recently, numerous researchers studied the corrosion properties of weldments fabricated by various process. [19][20][21][22] Based on the comprehensive literature survey, it is realized that there is a deficiency of systematic research to investigate the corrosion behaviour of dissimilar joints. In the present work, AA 6061 aluminium alloy (3 mm) with low carbon steel dissimilar butt joints were fabricated using CMT welding to improve the corrosion resistance and mechanical properties.…”