Corrosion of metal is a severe issue in any industry which is considered to involve many costs. The use of acid solution during cleaning to get rid of rust in industries may contribute to metal corrosion. Since corrosion impact is causing worries, especially in many industries, the application of a corrosion inhibitor is required to reduce the rapid deterioration reaction of a metal surface that is exposed to corrosion ‘boosters’ like oxygen gas and water. A corrosion inhibitor, which is [Zn(TAC)]Cl, was produced from the reaction between thiacetazone (TAC) with ZnCl2 in an acetonitrile solvent with ratio 1:1 (ligand:metal). The elemental analysis (C, H, N, and S), FT-IR, UV-Visible, melting point, gravimetric analysis, and molar conductivity were used to characterize the synthesized complex. Based on infrared spectra and electronic transitions, the shifting of a complex from the ligand indicates that the ligand is coordinated to the metal ion through carbonyl O, azomethine N, and thiolate S; thus, producing a tridentate complex. Melting point for the complex was higher than ligand. [Zn(TAC)]Cl was gained after being confirmed by 1:1 electrolyte behavior and elemental analysis calculations. A metal oxide, ZnO, was formed with the calculated percentage of Zn(II) ion, 13.66 % after combustion through the gravimetric analysis. [Zn(TAC)]Cl portrayed better inhibitory action against corrosion of mild steel as compared to the ligand in both acidic media, H2SO4 and HCl. A higher concentration of inhibitor gave a higher percentage of corrosion inhibition efficiency.
Mild steel plays an essential part in many construction industries due to its low cost and excellent mechanical properties. However, the use of strong acid in pickling, construction, and oil refining processes adds to a serious corrosion problem for mild steel. Two Cu(II) dithiocarbamate (DTC) complexes were successfully synthesised, namely Cu(II) ethyl-benzyl DTC (Cu[EtBenzdtc]2) and Cu(II) butyl-methyl DTC (Cu[BuMedtc]2) complexes, by a condensation reaction and subsequently used to scrutinise the corrosion resistance activity towards mild steel in acidic media. The proposed structures of complexes were characterised by using the Fourier transform infrared (FTIR) and ultraviolet-visible (UV-Vis) spectroscopies. The melting point for Cu[EtBenzdtc]2 was found around 362–375°C, and 389–392°C for Cu[BuMedtc]2. The percentages of Cu(II) found in Cu[EtBenzdtc]2 and Cu[BuMedtc]2 were 7.6% and 7.5%, respectively. Both complexes were non-electrolyte based on the molar conductivity analysis. Their corrosion inhibition performances were tested by using a weight loss measurement. Cu[BuMedtc]2 showed a good result as a corrosion inhibitor compared to Cu[EtBenzdtc]2. The complexes showed good effectiveness in sulfuric acid (H2SO4) compared to hydrochloric acid (HCl) solution. Furthermore, Cu[BuMedtc]2 showed a good result as a corrosion inhibitor compared to Cu[EtBenzdtc]2 with the highest percentage of corrosion inhibition recorded at 91.8%. Meanwhile, the highest percentage of corrosion inhibition shown by Cu[EtBenzdtc]2 was only 86.9%. The lowest corrosion rate shown for Cu[BuMedtc]2 was 8.1944×10-4 cm-1 h-1. Meanwhile, the Cu[EtBenzdtc]2 showed the lowest corrosion rate only at 1.3194×10-3 cm-1 h-1. This implies that Cu[BuMedtc]2 showed lower corrosion rate but higher inhibition efficiency compared to Cu[EtBenzdtc]2.
Layered double hydroxide (LDH)-based nanocomposite, created by interacting LDH with another nanoparticles usually applied in the area of environmental, catalytic, industrial and biomedical field. In this study, a new herbicide delivery system was developed through the intercalation of Magnesium Aluminiumlayered double hydroxide (MAN host) with 4-chlorophenoxyacetic acid (4-CPA). This intercalation was done by using co-precipitation method at pH 10 with different concentration of 4-CPA which were 0.5 M and 0.7 M. The successful intercalation was obtained at 0.7 M Magnesium Aluminium-4-chlorophenoxyacetic acid (MAC) and had been confirmed through several analysis. Firstly, the XRD pattern shows expansion of basal spacing shifted from 8.9 Å to 9.3 Å. This result supported by the FTIR-ATR spectrum that shows the disappearance nitrate peak (NO3 - ) and appearance of carboxylate ion (COO- ) peak at 1596 cm-1 . Furthermore, this intercalation was validated with the result of surface morphology by FESEM. The controlled release study of 4-CPA from 0.7 M MAC shown sodium carbonate solution released the percentage of 4-CPA higher than tap water. This study has signifies MAC as a safer agent of agrochemicals by reducing the dosage of herbicide in the agriculture field and protect the herbicide through encapsulation system.