Investigation of polyacrylamide containing capsaicin monomer as a novel corrosion inhibitor for mild steel in hydrochloric acid

A comparison study in terms of inhibition performance between oil palm empty fruit bunch (OPEFB) extract and OPEFB powder against mild steel corrosion in 1 M hydrochloric acid was evaluated using weight loss technique and adsorption isotherms. OPEFB extract and powder were prepared at various concentrations of 0.2%, 0.4%, 0.6%, 0.8%, and 1.0% (v/v) and dosages of 0.2, 0.4, 0.6, 0.8, and 1.0 g, respectively. The results showed that OPEFB extract achieved higher inhibition efficiency (IE) at high concentration and short immersion time compared to OPEFB powder. Despite having lower IE, OPEFB powder seemed to have better behavior; 6.6% IE increment at longer immersion time, gradual release of active compounds and stronger adsorption capacity. Fourier transform infrared (FTIR) and energy-dispersive X-ray studies confirmed the presence of active compounds in OPEFB extract and powder that is responsible for inhibition. Thermodynamic study revealed that both OPEFB extract and powder obeyed Langmuir isotherm and worked through physical adsorption.Overall, OPEFB powder is concluded to have better performance as corrosion inhibitor compared with OPEFB extract. K E Y W O R D Sacid corrosion, acid solutions, corrosion inhibitor, mild steel

Section: Resultssupporting

confidence: 85%

Oil palm empty fruit bunch extract and powder as an eco‐friendly corrosion inhibitor for mild steel: A comparison study

Haris

Sobri

Yusof

et al. 2019

“…Though the inhibition started to decrease after 4 days, the corrosion inhibition efficiency for 1 week was above 90%, and R ct was still higher than that of the blank, indicating good stability. [ 16 ]…”

Section: Resultsmentioning

confidence: 99%

“…According to previous reports, the hydrophobically associated polymer (HAP), a water‐soluble polymer with a small number of hydrophobic groups on the hydrophilic macromolecular chain with excellent thermal, salt, and shear resistance, also known to be a nontoxic, biodegradable, and environment‐friendly material has attracted extensive attention. [ 13–15 ] Therefore, HAPs are mainly used in improving oil production [ 16,17 ] ; however, little attention has been focused on exploring their applications as corrosion inhibitors.…”

Section: Introductionmentioning

confidence: 99%

Investigation of a hydrophobically associating AMAHS polyacrylamides: A new corrosion inhibitor for mild steel in HCl

Rao

Zhang

et al. 2020

Self Cite

A polyacrylamide with capsaicin‐derived monomers (AM–MAA–AMPS–HMBA–SMA; AMAHS) was synthesized and investigated as a novel environment‐friendly polymer inhibitor for Q235 mild steel at 25°C in 1 M HCl solution. The inhibition efficiency was evaluated by weight loss measurements, electrochemical experiments, and surface investigation methods as well as by theoretical calculations. Experimental results indicated that the efficiency of AMAHS was up to 94.86% at the concentration of 2 g/L. Electrochemical tests and surface morphology analysis showed that AMAHS served as a mixed‐type corrosion inhibitor, which could be adsorbed and self‐assembled on the surface of mild steel forming a highly hydrophobic protective film (contact angle of 172°). Density functional theory calculations revealed that heteroatoms in AMAHS, such as O, N, S, are active sites in forming coordination bonds with surface iron atoms. In addition, hydrophobic groups played an important role in protecting the metal surfaces from corrosion media.

“…

K_{ads}

is also linked to standard free energy of adsorption by the following equation:

Δ {italicG}_{ads}^{°} = \mp RT In (55.5 {italicK}_{ads}),

where R is the gas constant and T is the absolute temperature. The value of 55.5 is the concentration of water in solution in mol/L.…”

Section: Resultsmentioning

confidence: 99%

New surfactants N‐alkyl‐N,N‐dimethyl‐N‐(3‐thienylmethylene)ammonium bromides: Preparation and anticorrosion evaluation

Chen

Jiang

Cheng

et al. 2019

A new series of N‐alkyl‐N,N‐dimethyl‐N‐(3‐thienylmethylene)ammonium bromides (designated as NTA‐n, n = 8, 10, 12, 14, and 16) were synthesized. The electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization showed that NTA‐n could protect availably X70 steel from attack of HCl with an inhibition efficiency of about 95%. And the inhibition ability follows the following sequence: NTA‐8 < NTA‐10 < NTA‐12 < NTA‐14 < NTA‐16, suggesting that prolonging alkyl chain may enhance the inhibition capacity of the molecules. Theoretical investigation backs up well the experiment results. The correlation of theoretical calculation with the experiment results illustrated clearly double logarithmic relations between the corrosion current and the computed quantum chemical parameters such as the highest occupied molecular orbital energy ( E HOMO), energy gap (ΔE), molecular volume ( ν), electronegativity ( χ), the total energy of iron crystal with the adsorbed inhibitor molecule ( E total), the interaction energy of Fe (1 0 0) surface and inhibitor molecules ( E inhibitor), while an equation resembling Hammet relation was existed between the corrosion currents and the fraction of electrons transfer (ΔN). These linear correlations suggest the relation of the inhibitor structure with its inhibition activity: long alkyl chain and electron donating groups in NTA‐n will enhance the corrosion efficiency.