A new ketal cyclic from ethyl 9,10-dihydroxyoctadecanoate with acetone had been synthesized by reflux and sonochemical method. The synthesis was performed via several steps of reaction, i.e.: transesterification, hydrolysis, oxidation with 1% KMnO4 in basic condition, esterification, and ketalization. The structures of the products were confirmed by FTIR, GC-MS, 1H- and 13C-NMR spectrometers. Direct transesterification of used cooking oil produced a mixture of ethyl ester in 82.94% yield meanwhile hydrolysis of this mixture gave free fatty acids mixture in 88.46% yield. Hydroxylation reaction of free fatty acids mixture yielded a white powder of 9,10-dihydroxyoctadecanoic acid in 46.52% yield. Esterification of 9,10-dihydroxyoctadecanoic acid and ethanol catalyzed by sulfuric acid with reflux condition for 4 hours and sonochemical method, respectively yielded 90% and 93.8% of ethyl 9,10-dihydroxystearate. In the other side, the utilization of KSF montmorillonite as catalyst conducted with reflux gave 52% in yield of ester. Furthermore, the use of acetone in 45 minutes sonochemical method with montmorillonite KSF catalyst gave cyclic ketal (ethyl 8-(2,2-dimethyl-5-octyl-1,3-dioxolan-4-yl)octanoate) as a yellow viscous liquid in 53.30% yield. From physicochemical properties –density, kinematic viscosity, viscosity index, total acid number, total base number and iodine value- gave the conclusion that this novel compound is potential biolubricant candidates to be developed.
MDHO dengan rendemen 93,[80][81]. Penggunaan siklopentanon pada metode sonokimia selama 45 menit menghasilkan cairan kental berwarna kuning metil 8-(3-oktil-1,4-dioksaspiro[4.4]nonan-il)oktanoat dengan rendemen 50,51%. Senyawa lain,
A research has been conducted to investigate the adsorption behavior of Pb(II) and Cr(III) onto polypropylcalix[4]arene polymer. The polypropylcalix[4]arene polymer was synthesized in the presence of H2SO4 catalyst and chloroform under N2 condition for 5 h using 25-allyloxy-26,27,28-trihydroxycalyx[4]arene as the precursor. The Polymer was obtained as yellow crystal with melting point of 288-290 °C and its relative molecular weight was 44.810 g.mol-1. The application of polypropylcalix[4]arene for trapping heavy metal cations and its adsorption model were examined by stirring the suspension of the calixarene in the sample solutions for various pH, time, and concentration of Pb(II) and Cr(III) solution. Effect of pH on batch experiments for the mentioned ions indicated that the optimum pH for metal binding were 5 for lead(II) and chromium(III). The adsorption model of metal ions on polypropylcalix[4]arene followed both the pseudo second order adsorption of Ho's and Langmuir isotherm adsorption kinetics models with rate constant (k) were 6.81 x 101 min-1 for Pb(II) and 2.64 x 10-2 min-1 for Cr(III). The adsorption equilibrium constant, K, were 5.84 x 105 L.mol-1 for Pb(II) and 4.66 x 105 L.mol-1 for Cr(III). The maximum adsorption capacity of polypropylcalix[4]arene to Pb(II) and Cr(III) were 16.31 and 18.14 mg.g-1 with adsorption energy of 32.90 and 32.34 kJ.mol-1, respectively. Keywords: polypropylcalix[4]arene, adsorption, Pb(II), and Cr(III)
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