Kinetics of the acid-catalyzed cardanol–formaldehyde reactions

Degradation of pentachlorophenol in a contaminated soil suspension using hybrid catalysts prepared via urea–formaldehyde polycondensation between iron(III)-tetrakis(p-hydroxyphenyl)porphyrin and humic acid

“…In addition, the peaks for the C-O stretching of phenol at approximately 1,270 cm -1 were reduced and broadened to a considerable extent, compared to the spectrum of FeTPP(OH) 4 alone. When a phenol resin is formed, significant broadening and a reduction in the intensity of peaks corresponding to phenol O-H stretching and C-O stretching have been reported (Yadav and Srivastava 2007). In other reports of IR spectra of phenol and phenol resins, a reduction and broadening in peaks at 1,610 cm -1 (C=C ring stretching) and at 1,270 cm -1 (phenol C-O stretching) have been reported (Poljanšek et al 2006).…”

“…HAs contain phenolic functional groups, which are potential binding sites for iron(III)-porphyrins. While phenolic resins are typically prepared by a polycondensation reaction between formaldehyde and phenol (Yadav and Srivastava 2007), a urea component can also be added to reaction mixture, which results in the formation of phenol-urea-formaldehyde cocondensed resins (He and Yan 2004). The co-condensation of formaldehyde and urea results in the formation of more complicated structures (e.g., -NH-CH 2 -NH-, -NH-CO-NH-, and so on), which also participate in the cross-linking between phenols.…”

A kinetic study of sucrose hydrolysis over Amberlite IR-120 as a heterogeneous catalyst using in situ FTIR spectroscopy

“…This technique has proven its applicability in bioprocesses [1,4,5], organic [2,3,6] and polymer [7,8] synthesis. It is also used in homogeneous [9,10] and bio catalysis [11]. Heterogeneous catalysis [12,13] is more efficient compared to homogeneous and enzymatic catalysis because of its certain advantages such as rigorous control of the reaction, reduction of the secondary product content, easier separation of catalyst from the reaction medium, lower cost of catalyst per unit of production and the possibility of piloting the catalytic processes at higher temperatures than in the case of enzyme processing [14].…”

A study on the kinetics of condensation reaction of cardanol and formaldehyde, part I

“…Earlier researchers were mainly concerned with the evaluation of the overall rate constant, first order or second order, or with the detection of the various components formed during the condensation reaction of phenol and formaldehyde. Acid catalysts, namely, dicarboxylic acids [12] and tricarboxylic acid [13], have been used earlier for the synthesis of cardanol-formaldehyde novolac resin. The acid strength of the dicarboxylic acid, as measured by the first dissociation constant k 1 , decreases with the increase in the number of bonds between the two carbonyl groups [12,13].…”

“…Acid catalysts, namely, dicarboxylic acids [12] and tricarboxylic acid [13], have been used earlier for the synthesis of cardanol-formaldehyde novolac resin. The acid strength of the dicarboxylic acid, as measured by the first dissociation constant k 1 , decreases with the increase in the number of bonds between the two carbonyl groups [12,13]. Organic sulfonic acid, namely, p-toluene sulphonic (PTSA) acid, has been used as a catalyst for the synthesis of phenolic novolac resin [14,15] in the past, but the literature pertaining to the synthesis of cardanol-formaldehyde novolac catalyzed by PTSA is more or less negligible.…”