Studies on the effect of long‐chain and head groups of nonionic surfactants synthesized from palm and coconut oil on the formation of silver nanoparticles

Abstract

Four fatty amides were synthesized using coconut and palm oil sources. The chemical structure of the as-prepared fatty acids was confirmed using Fourier Transform Infrared (FT-IR) and 1 H, 13 C NMR spectroscopy. The effect of different chain lengths and head groups of these compounds on Ag nanoparticles (NPs) synthesis was investigated. Ultraviolet-visible spectroscopic studies showed characteristic absorbance peaks (λ max ≈ 410 nm). FT-IR results indicated that the surfactant functionalities are responsible for the Ag NPs stability. The effect of fatty amides on the morphology and size distribution of the Ag NPs was investigated using transmission electron microscope (TEM). The TEM micrographs showed the formation of fine spherical morphology due to surfactant-mediated self-assembly with an average particle size of 1-3 nm. Dynamic light scattering (DLS) analysis showed the micellar self-assembly of Ag NPs-fatty amides. The effect of surfactant on the solution behavior was analyzed using surface tension measurements. Cocamide and palm DEA showed relatively low free energy (ΔG mic ) values, resulting in smaller particles with good distribution. Finally, the Ag NPs showed outstanding antimicrobial activity against Pseudomonas putida bacteria.

Synthesis of non-ionic, cationic, and anionic surfactant from coconut oil for remediation of diesel contaminated soil

“…Firstly, biodiesel was characterized by GC; methyl laurate was found in a more considerable proportion (56 %), followed by methyl myristate in 19%. We previously reported these results (Vázquez-Vélez et al, 2022), which are in accord with the literature (Jung et al, 2017), excluding other virgin oils (Qadariyah et al, 2022). Then, the three kinds of synthesized surfactants are obtained as a mixture of fatty acids in coconut oil.…”

“…On the other hand, coconut oil and its biodiesel were characterized by FTIR spectroscopy (figure 2), which we have reported previously (Vázquez-Vélez et al, 2022). Both spectra observed the stretching signals of the group C = O of ester at 1741 cm −1 and the C-O bond at 1167 cm −1 , a signal that presents greater intensity for the triglyceride.…”

“…The synthesis of the non-ionic surfactant: Cocamidodiethylmalate oligomer was carried through the aminolysis of methyl cocoate (1 mol) with diethanolamine (DEA, 1.1 mol) at 140 °C following the same method previously reported for the direct aminolysis of coconut oil (Vázquez-Vélez et al, 2022). TLC monitored the reaction until the complete formation of the product (2 hours).…”

“…and a gradient of 4 °C until reaching 240 °C for two min. The chromatogram peaks were identified with the commercial standards of methyl esters (C10-C18) according to their retention time, as reported in previous work [Vázquez-Vélez et al, 2022]. All products were analyzed by FTIR Spectroscopy, using the film technique in Bruker Tensor 27 equipment.…”

“…The most widely used non-ionic surfactants are polyoxides, polyesters, polyalcohols, and polysaccharides (Mao et al, 2015). In this work, the Cocodiethanolamide (CDEA) was synthesized from the aminolysis of the methyl cocoate with diethanolamine (DEA), whose process has been previously reported (Vázquez-Vélez et al, 2022). CDEA is widely used as a surfactant in the cosmetic industry (Rhein et al, 2007) and has been studied in soil remediation (Mao et al, 2015), but its toxicity increases at high concentrations (Ishiguro et al, 2016).…”