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Herein is the synthesis and effective use of an S‐naproxen (S‐NP) enantioselective adsorbent material with amino functionality for the enantioseparation of a (±)‐NP racemic mixture. To begin, the S‐NP enantiomer of (3‐aminopropyl)triethoxysilane was used to create an amide derivative (S‐NP–Si–NH2). In order to incorporate the S‐NP enantiomeric species into the cross‐linked material, the developed S‐NP–Si–NH2 derivative was combined with tetraethoxysilane (TEOS) and subjected base‐catalyzed sol–gel condensation polymerization procedure. The S‐NP is released from the cross‐linked matrix by alkaline hydrolysis and subsequent acidification, creating an enantioselective gap filled with cationic ions that are compatible with the S‐NP during recombination. With the use of elemental analysis, nuclear magnetic resonance (NMR), and Fourier transform infrared (FTIR) spectroscopy, it was verified that the performed chemical processes on the monomeric precursor and the resulting S‐NP molecularly imprinted material (S‐NP–Sil) were successful. Furthermore, the morphology alterations were analyzed using scanning electron microscopy images of the sorbent surface. The produced adsorbent particles were also used in the chiral separation of a (±)‐NP racemic combination utilizing a column approach, with encouraging separation results shown in both the first loading run (59% ee of R‐NP) and the second elution run (85% ee of S‐NP).

The objective of this research was to explore the impact of corrosion inhibition of some synthetic acrylamide derivatives 2-cyano-N-(4-hydroxyphenyl)-3-(4-methoxyphenyl)acrylamide (ACR-2) and 2-cyano-N-(4-hydroxyphenyl)-3-phenylacrylamide (ACR-3) on copper in 1.0 M nitric acid solution using chemical and electrochemical methods, including mass loss as a chemical method and electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization (PP) as electrochemical methods. By Fourier-transform infrared spectroscopy (FTIR), proton nuclear magnetic resonance (1HNMR), and mass spectroscopy (MS) methods, the two compounds were verified and characterized. There is evidence that both compounds were effective corrosion inhibitors for copper in 1.0 M nitric acid (HNO3) solutions, as indicated by the PP curves, which show that these compounds may be considered mixed-type inhibitors. With the two compounds added, the value of the double-layer capacitance was reduced. In the case of 20 × 10−5 M, they reached maximum efficiencies of 84.5% and 86.1%, respectively. Having studied its behavior during adsorption on copper, it was concluded that it follows chemical adsorption and Langmuir isotherm. The theoretical computations and the experimental findings were compared using density functional theory (DFT) and Monte Carlo simulations (MC).

In the current work, synthetic polyamide nylon fibers were modified via the strategy of surface molecular imprinting to develop enantio-selective adsorbent fabrics for chiral recognition of D-phenyllactic acid (D-PhLA). The nylon fibers were first modified by grafting of polyacrylamide and then the incorporated amide groups were converted into functional amino groups via treatment with NaOCl (Hofmann degradation). The amino-functionalized nylon fibers (Ny-NH 2 ) were interacted with the targeted D-PhLA enantiomer before crosslinking the amino-containing grafted chains with glutaraldehyde crosslinker followed by leashing the template D-PhLA out of the formed surface polymeric matrix by lowering the pH to 1 to finally produce the desired enantio-selective adsorbent fibers DP-Ny. Different instrumental methods such as elemental analysis, Fourier transform infrared spectroscopy, XRD and TGA were employed to examine all the synthetic procedures. SEM was also utilized to observe the morphological appearances of both native and modified nylon fibers. Moreover, the optimum extraction of D-PhLA was found to occur at pH 7. Isotherm studies of the prepared DP-Ny fibers obeyed the common Langmuir linear equation with q m values 130 ± 2 and 75 ± 1 mg g −1 in the case of D-PhLA and L-PhLA, respectively. Furthermore, the enantiomeric resolution of (±)-PhLA racemate was successfully carried out by a column technique with enantiomeric excess reaching approximately 78%.