Preparation, characterization and scale performance of scale inhibitor copolymer modification with chitosan

Synthesis, characterization and properties of a novel environmentally friendly ternary hydrophilic copolymer

A novel environmentally friendly scale inhibitor was synthesized by the free radical polymerization of itaconic acid (IA), acrylamide (AM), and sodium p-styrene sulfonate (SSS). The structures of the copolymers were characterized using FTIR, UV, and ¹H-NMR, which proved successful in obtaining the expected target structures. The synthesis conditions such as monomer ratio, initiator dosage, titration time, and reaction temperature were optimized by the static scale inhibition method, and the expected polymeric scale inhibitor with a competent scale inhibition performance was obtained. The copolymer conversions at different temperatures were obtained indirectly by bromination titration, and the relationship between the molecular weight of the polymer and the scale inhibition performance at different reaction temperatures was also investigated by GPC. The results showed that the copolymer had a good ability to control calcium carbonate scaling, and the inhibition rate of CaCO₃ reached 84.7% at a dose of 30 mg L^-1. The microscopic morphology and structure of calcium scales were analyzed by SEM, FTIR, and XRD, and it was concluded that the copolymer could change the crystallization path of calcium carbonate from stable calcite to vaterite. That could be dispersed in water. The proposed inhibition mechanism suggests that surface complexation between polymer functional groups and Ca²⁺ leads to excellent solubility of the complexes. These findings suggest that the prepared green copolymers have great potential for oilfield applications.

The oligosuccinimide and modified polysuccinimide as green corrosion and scale inhibitors

Corrosion and scale formation are crucial issues in the petroleum industry. They can inflict metal or other materials breakdown, leading to environmental pollution. Applying scale and corrosion inhibitors is a cost-effective and efficient way of controlling corrosion and scale formation in a fluid system. Much research has been conducted to obtain cheap and safe corrosion or scale inhibitors. Modified polysuccinimides (PSI) are among the organic compounds reported as effective and environmentally friendly corrosion as well as scale inhibitors. The use of various novel green corrosion and scale inhibitors from modified PSI for controlling corrosion reactions or scale formation has not been extensively reviewed. Hence, this review highlights recent studies on preparing PSI/OSI, modifying PSI, and analyzing their performance as corrosion and scale inhibitors. Adsorption study, biodegradation performance, computational quantum study, limitations, and prospects of the inhibitors are also discussed. Therefore, i this work provides an overview of novel modified PSI as effective and safe corrosion or scale inhibitors in different media, for various metals, and on a different scale.

Chitosan as a Canvas for Studies of Macromolecular Controls on CaCO3 Biological Crystallization

A mechanistic understanding of how macromolecules, typically as an organic matrix, nucleate and grow crystals to produce functional biomineral structures remains elusive. Advances in structural biology indicate that polysaccharides (e.g., chitin) and negatively charged proteoglycans (due to carboxyl, sulfate, and phosphate groups) are ubiquitous in biocrystallization settings and play greater roles than currently recognized. This review highlights studies of CaCO₃ crystallization onto chitinous materials and demonstrates that a broader understanding of macromolecular controls on mineralization has not emerged. With recent advances in biopolymer chemistry, it is now possible to prepare chitosan-based hydrogels with tailored functional group compositions. By deploying these characterized compounds in hypothesis-based studies of nucleation rate, quantitative relationships between energy barrier to crystallization, macromolecule composition, and solvent structuring can be determined. This foundational knowledge will help researchers understand composition-structure-function controls on mineralization in living systems and tune the designs of new materials for advanced applications.

State of art bio-materials as scale inhibitors in recirculating cooling water system: a review article

During the operation of the circulating cooling water system, inorganic scale deposition may cause technical problems, such as reduction of heat transfer efficiency in cooling systems and obstruction of pipes. In the industry, chemicals are often used as scale inhibitors in scale deposition control, antiscalants popular in industry are generally phosphorus and nitrogen-containing chemicals, which may lead to eutrophication. However, increasing environmental concern and discharge limitations have guided antiscalants to move toward biodegradability, nontoxicity and cost-effectiveness. This paper reviews current research on the application of using bio-materials as scale inhibitors, including proteins and amino acids, polysaccharides, plant extracts, microbial reagents, and microbiological products. The non-bioaccumulation, low cost, readily biodegradability and sustainably available characters promote the development of green-scale inhibitor chemistry.

Scale inhibition in industrial water systems using chitosan‐alginate mixture

The study aims to establishing the possibility of using eco‐friendly natural polymers to formulate scale inhibitor for industrial water applications. The performance of a blend of two natural polymers, chitosan and sodium alginate as scale inhibitor in comparison with a commercially available inhibitor formulation, HEDP (Hydroxyethylidene, 1‐Diphosphonic Acid), is carried out using electrochemical measurements, conductivity and NACE test complemented with crystals morphology characterization using optical and electronic microscopic examination. Overall results show that chitosan is more efficient for the inhibition of calcium carbonate scales formation, whilst it has poor efficiency in the inhibition of sulfate scales, whereas sodium alginate has the highest efficiency in inhibiting calcium sulfate scales. However, the addition of sodium alginate to chitosan, as a package, has a dual control effect on carbonate and sulfate scale formation with good efficiency compared to HEDP. This new phosphorus‐free package represents an effective antiscalant to have green environment.

The synthesis of polyaspartic acid derivative PASP-Im and investigation of its scale inhibition performance and mechanism in industrial circulating water

A polyaspartic acid derivative (PASP-Im) as a novel scale inhibitor was synthesized by a simple green synthesis route with polysuccinimide and iminodiacetic acid as the starting materials. The as-synthesized PASP-Im was characterized via nuclear magnetic resonance spectroscopy (¹H-NMR) and Fourier transform infrared spectrometry (FT-IR), and its scale inhibition performance was evaluated by a static scale inhibition method. Moreover, scanning electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and density functional theory computational studies were conducted to explore the scale inhibition mechanism of PASP-Im. The findings indicate that the as-synthesized PASP-Im exhibits better antiscale performance against the CaCO₃ deposits than the unmodified PASP because of the introduction of iminodiacetic acid group. It also can change the crystallization path of calcium carbonate from stable calcite to vaterite that is dispersible in water, thereby resulting in great changes in the morphology of the CaCO₃ scale. Furthermore, the O and N atoms in the negatively charged functional groups (such as –NH₂ and –COOH) of PASP-Im can interact with calcium ions to block the active growth point of CaCO₃ crystals, which also accounts for the excellent antiscale performance of PASP-Im. With new insights into the synergy between the functional groups of the antiscale molecule and scale-forming ions, this approach would be helpful towards the development of novel high-performance anti-scaling macromolecules.

A polyaspartic acid derivative (PASP-Im) as a novel scale inhibitor was synthesized by a simple green synthesis route with polysuccinimide and iminodiacetic acid as the starting materials.

A Novel Eco-Friendly Scale and Corrosion Inhibitor Modified by β-Cyclodextrin

A polymer, β-MEA, was synthesised from β-cyclodextrin (β-CD), 3-chloro-2-methylpropene (MAC), epoxysuccinic acid (ESA), and 2-acrylamido-2-methyl propane sulfonic acid (AMPS) with a (NH4)2S2O8-NaHSO3 redox initiator system by aqueous solution radical polymerisation. β-MEA was characterised by means of IR spectroscopy, time-of-flight mass spectrometry, gel permeation chromatography, and thermogravimetric analysis. Its structure, molecular weight, thermal stability, scale and corrosion inhibition performance and mechanism were investigated. The results verified that β-MEA achieves a better scale inhibition efficiency for BaSO4 compared with poly(aspartic acid) (PASP) (100 % cf. 94.9 % at a concentration of 20 mg L−1) and a better corrosion inhibition efficiency of N80 carbon steel in saline water compared with PESA (91.2 % cf. 79.7 % at a concentration of 1 g L−1). The BaSO4 was characterised by scanning electron microscopy (SEM) and X-ray diffraction to investigate the crystal morphology of the scale. Primary research on the mechanism for corrosion inhibition was carried by SEM-chemical analysis.