Inhibition Effect of Environment-Friendly Inhibitors on the Corrosion of Carbon Steel in Recirculating Cooling Water

Green polyaspartic acid as a novel permanganate activator for enhanced degradation of organic contaminants: Role of reactive Mn(III) species

Attention has been long focused on enhancing permanganate (Mn(VII)) oxidation capacity for eliminating organic contaminants via generating active manganese intermediates (AMnIs). Nevertheless, limited consideration has been given to the unnecessary consumption of Mn(VII) due to the spontaneous disproportionation of AMnIs during their formation. In this work, we innovatively introduced green polyaspartic acid (PASP) as both reducing and chelating agents to activate Mn(VII) to enhance the oxidation capacity and utilization efficiency of Mn(VII). Multiple lines of evidence suggest that Mn(III), existing as Mn(III)-PASP complex, was generated and dominated the degradation of bisphenol A (BPA) in the Mn(VII)/PASP system. The stabilized Mn(III) species enabled Mn(VII) utilization efficiency in the Mn(VII)/PASP system to be higher than that in Mn(VII) alone. Moreover, the electrophilic Mn(III) species was verified to mainly attack the inclusive benzene ring and isopropyl group to realize BPA oxidation and its toxicity reduction in the Mn(VII)/PASP system. In addition, the Mn(VII)/PASP system showed the potential for selectively oxidizing organic contaminants bearing phenol and aniline moieties in real waters without interference from most of coexisting water matrices. This work brightens an overlooked route to both high oxidation capacity and efficient Mn(VII) utilization in the Mn(VII)-based oxidation processes.

Novel Polyepoxysuccinic Acid-Grafted Polyacrylamide as a Green Corrosion Inhibitor for Carbon Steel in Acidic Solution

Utilizing green corrosion inhibitors has been classified among the most efficient and economical mitigation practices against metallic degradation and failure. This study aims to integrate the features of green and complementary properties of polyepoxysuccinic acid (PESA) and polyacrylamide (PAM) for steel corrosion inhibition. A novel PESA-grafted-PAM (PESAPAM) has been first-ever synthesized in this research study and deployed as a corrosion inhibitor for C-steel in 1.0 M HCl solution. Eco-toxicity prediction confirmed the environmentally friendly properties acquired by the synthesized inhibitor. Electrochemical, kinetics, and surface microscopic studies were carried out to gain a holistic view of C-steel corrosion behavior with the PESAPAM. Furthermore, the performance of PESAPAM was compared with that of the pure PESA under the same testing conditions. Results revealed predominant inhibitive properties of PESAPAM with an inhibition efficiency (IE) reaching 90% at 500 mg·L^-1 at 25 °C. Grafting PAM onto the PESA chain showed an overall performance improvement of 109% from IE% of 43 to 90%. Electrochemical measurements revealed a charge transfer-controlled corrosion mechanism and the formation of a thick double layer on the steel surface. The potentiodynamic study classified PESAPAM as a mixed-type inhibitor. Furthermore, the investigation of C-steel corrosion kinetics with the presence of PESAPAM predicted an activation energy of 85 kJ·mol^-1, correlated with a physical adsorption behavior. Finally, performed scanning electron microscopy and energy-dispersive X-ray analyses confirmed the adsorption of PESA and PESAPAM, with superior coverage of PESAPAM onto the steel surface.

Polymers Decorated with Functional Motifs for Mitigation of Steel Corrosion: An Overview

Corrosion is a hazardous phenomenon having a devastating impact on technological and industrial applications, particularly in the oil and gas industries. Therefore, controlling the corrosion of metals is an important activity of technical, economical, environmental, and aesthetical importance in order to save huge expenses in materials, equipment, and structure. The use of corrosion inhibitors is one of the best options for controlling the metallic corrosion in various corrosive media. Numerous problems aroused with the use of inorganic and small molecule organic corrosion inhibitors, and the use of polymeric corrosion inhibitors came into limelight. This review article provides an overview of the recent development of different classes of corrosion inhibitors with special emphasis on different functional motifs of natural, synthetically modified natural, and synthetic polymeric materials. The significance, mechanism, and challenges of using polymeric materials as corrosion inhibitors are also highlighted in the review.

Experimental and Electrochemical Research of an Efficient Corrosion and Scale Inhibitor

A novel corrosion and scale inhibitor (TPP) containing tobacco stem extract (TSE), polyepoxysuccinic acid (PESA), and polyaspartic acid (PASP) was obtained by the optimal proportion of the orthogonal test. The anticorrosion effect of TPP for carbon steel was researched by static weight-loss method, on-line simulated dynamic test, electrochemical measurement, and scanning electron microscopy (SEM). The results showed that TPP could protect carbon steel efficiently with a maximal corrosion inhibition rate of 85.7% and it was a mixed-type corrosion inhibitor, mainly exhibiting cathode suppression capacity. Simultaneously, the results of calcium carbonate deposition experiment indicated that the scale inhibition rate of TPP was up to 100%.

A novel polyaspartic acid derivative with multifunctional groups for scale inhibition application

Polyaspartic acid is a green biodegradable antiscalant and widely applied in water treatment field. However, its scale inhibition efficiency is not prominent, especially for calcium orthophosphate. So we introduced acylamino and hydroxyl groups simultaneously to prepare a novel polyaspartic-acid derivative (PASPTU) with multifunctional groups by the reaction of polysuccinimide with threonine and urea. The graft copolymer was analyzed by using nuclear magnetic resonance, gel permeation chromatography, thermogravimetric analyzer and Fourier transform infrared spectroscopy. Its scale inhibition performance for calcium orthophosphate, calcium sulfate and calcium carbonate was evaluated. The findings showed that the scale inhibition rates of the graft copolymer reached up to 100% for calcium orthophosphate, 100% for calcium sulfate and 91% for calcium carbonate at certain dosages. The findings above showed that the copolymer had excellent scale inhibition efficiency for calcium salts in water treatment processes.

Origin of gypsum growth habit difference as revealed by molecular conformations of surface-bound citrate and tartrate

Correlation of the microscopic gypsum–organic interfacial structural information with the macroscopic crystal morphology difference induced by different organic acids.

Preparation and Application of Double-Hydrophilic Copolymer as Scale and Corrosion Inhibitor for Industrial Water Recycling

A novel double-hydrophilic copolymer (acrylic acid-isoprenyl polyethoxy carboxylate, AA-TPEL) is synthesized and the structural properties are identified by FT-IR, 1HNMR and GPC analyses. The inhibitory behavior of the copolymer is determined by using a static scale inhibition method. It is shown that AA-TPEL exhibits an excellent ability to control the formation of CaCO3 scale with an inhibition efficiency of 88.67 % at the 8 mg L–1, and it still maintains a superior efficiency even at increasing solution temperature, pH, and Ca2+ concentration. Weight loss test, potentiodynamic polarization and electrochemical impedance spectroscopy are applied to investigate the inhibition efficiency on mild steel corrosion. All measurements show that, AA-TPEL acts as an efficient corrosion inhibitor and also displays a superior ability to prevent the corrosion of mild steel with approximately 83.21 % inhibition efficiency at the low level of 10 mg L–1. Scanning electron microscopy (SEM) and X-ray powder diffraction (XRD) are used to characterize the surface morphology of CaCO3 and steel.

Biopolymer from Tragacanth Gum as a Green Corrosion Inhibitor for Carbon Steel in 1 M HCl Solution

A biopolymer from tragacanth gum, arabinogalactan (AG), was investigated for its adsorption and corrosion inhibition traits for carbon steel corrosion in 1 M HCl. Gravimetric method, potentiodynamic polarization measurements, electrochemical impedance spectroscopy, UV-visible spectroscopy, scanning electron microscopy, and atomic force microscopy were used to judge the adsorptive nature of AG in the acid solution. The inhibition efficiency improved with an increase in AG concentration and temperature of the acid solution. Thermodynamic and activation parameters (ΔG ads, E a, ΔH, and ΔS) were also calculated and discussed. The adsorption of AG favored Langmuir adsorption isotherm. The results of corrosion tests confirmed that AG could serve as an efficient green corrosion inhibitor for the carbon steel in 1 M HCl, yielding high efficiency and a low risk of environmental pollution. Theoretical quantum chemical and Monte Carlo simulation studies corroborated the experimental results.

Carbon steel corrosion: a review of key surface properties and characterization methods

The effects of surface morphology, defects, texture and energy on carbon steel corrosion are elucidated along with relevant characterization methods.

Synthesis and characterization of a biodegradable polyaspartic acid/2-amino-2-methyl-1-propanol graft copolymer and evaluation of its scale and corrosion inhibition performance

Herein, a novel polyaspartic acid derivative, polyaspartic acid/2-amino-2-methyl-1-propanol graft copolymer (PASP/AMP), was synthesized via a ring-opening reaction using polysuccinimide (PSI) and 2-amino-2-methyl-1-propanol (AMP).