Esterification amberlyst

Esterification (Amberlyst-15) n-butyl acetate from acetic acid and n- butanol... 

Very recently, Nolan et al. studied several acidic polymeric catalysts for the esterification of fatty acids. The highest FFA conversion (45.7%) was obtained over strong acidic macroreticular polymer catalysts AmberlysH 15 at 60°C compared with Amberlyst 35, Amberlyst 16, and Dowex HCR-W2. 

Esterification over Amberlyst BD20 was evaluated by processing a model mixture in a fixed-bed reactor. The model reaction mixture was prepared by dissolving 10 wt.% of pure stearic acid (> 97%, Fluka, Germany) in a low-acid vegetable oil (0.04 %) bought in the supermarket. Methanol (> 99.5%) was used without any preliminary treatment. 

Rohm and Haas Bodiesel Technology Amberlyst BD20 FFA Esterification Process Flow Diagram... 

Yuen et al. [24] first demonstrated the nature of the information that can be obtained regarding chemical mapping within a fixed-bed reactor, using the liquid phase esterification of methanol and acetic acid catalyzed within a fixed bed of H+ ion-exchange resin (Amberlyst 15, particle size 600-850-pm) catalyst as the model... 

The effect of the mode of heating was also studied in heterogeneously catalyzed esterification of acetic acid by isopentyl alcohol in the presence of Amberlyst-15 cation exchange resin catalyst [38], Scheme 10.2. 

Recently, the immobilization of dialkylmetal oxides, particularly dibutyltin oxide, on Amberlyst 45 ion-exchange resin, has been proposed for the esterification-transester-ification rcactionon model mixturcsatO.S °C,reaching92-100%conversioninll h [23]. 

Cation-exchange resin such as Amberlyst 15 has been used for the esterification of isosorbide with -octanoic acid [132], giving the corresponding diesters in 98% yield. 

For a higher accuracy of the isotherm, the activities in the liquid phase instead of the concentrations can be used. If a thermodynamic model for the computation of the solid-phase activities exists, the equilibrium concentration q and qi can also be calculated from the condition of equal activity, as was done for example for the esterification of acetic acid on Amberlyst 15 using the Flory-Huggins activity model for the solid phase and a UNI FAC model for the liquid phase [17]. 

W. Yu, K. Hidajat, A. K. Ray, Determination of adsorption and kinetic parameters for methyl acetate esterification and hydrolysis reaction catalyzed by Amberlyst 15. Appl. Catal. A, 2004, 260 (2), 191-205. 

Esterification.1 Acids are esterified in high yield when dissolved in methanol containing Amberlyst 15. The reaction is effected at 25° in 4-14 hours with yields >80%. Chiral acids are esterified without epimerization. 

Figure 14.9 Esterification of dodecanoic acid with 2-ethylhexanol comparison of homogeneous and heterogeneous acid catalysts at 130°C (left) comparison of Amberlyst, Nafion and sulfated zirconia (SZ) at 150°C (right). The amount of solid catalyst, 3wt%, refers to the total mass of reactants [23, 24].

Figure 15.9 shows the esterification of different saturated carboxylic acids with dicyclopentadiene. In all depicted experiments the carboxylic acid/dicyclo— pentadiene molar ratio is about 4 and the amount of catalyst is 10% by weight of dicyclopentadiene at a reaction temperature of 80°C. In this reaction the Nafion/silica composite catalyst is more active compared to the Amberlyst resin, in particular with respect to the amount of the acid groups on the resin. 

Fig. 15.10 Esterification of 47 with different carboxylic acids over Nafion/silica composites with different amount of Nafion and over Amberlyst 15...

In the past few years, a large number of CD processes on esterification using Katapak packing such as Katapak-S or Multipak packing together with solid acid catalyst such as Amberlyst 15 have been reviewed in detail and hence these processes will not be reviewed here. All these processes operate at mild temperature and pressure with conversions and selectivities in excess of 95% and in some cases close to 100%. 

The results show that the K1481 catalyst is more active by a factor of 2 than Amberlyst 119, which indicates that particle size influences the esterification rate. As the K1481 catalyst is a powder, it has a significant outer surface area and acid centres located on this surface are easily accessible. 

Sulfonic acid resins can be used as solid catalysts for esterifications and other acid-catalyzed reactions. Am-berlyst 15 was a more effective catalyst for the preparation of esters of phenethyl alcohol and cyclohexanol than sulfated zirconia, an acid clay, and dodecatungstophos-phoric acid.113 (Amberlyst and Amberlite are trademarks of Rohm Haas.) (See Chap. 6 for more detail on solid acids and bases.) The same catalyst gave 86-96% yields of hydroxyesters when a lactone was stored with a hy-droxyacid.114 Diols can be monoacylated in 58-92% yields by transesterification with ethyl propionate in the presence of Dowex 50W (a product of the Dow Chemical Co.).115 Modification of the sulfonic acid resin with 2-mercaptoethylamine produced a catalyst for the reaction of phenol with acetone to produce bisphenol A (5.30) in 99.5% yield.116 After 20 cycles the yield was still 98.7%. When used as catalysts, ion-exchange resins can last for 6 months to 2 years. 

By reaction of phenols with bifunclional molecules, which are able to alkylate and to esterify, several coumarin derivatives have been prepared using H-Bela as the catalyst. Thus resorcinol and propynoic acid react at 150 °C in p-chlorotolucnc as the solvent towards the perfumery ingredient umbelliferone (7-hydroxycoumarin) in good yield, 60 %, [84], Amberlyst-15 gave 40 % yield. II-Beta catalyzes the esterification as well as the ring closure alkylation step. 

Another solid-aeid catalyzed reaction in which the Nafion-silica composites are much more active than the non-supported pure resin and Amberlyst-15 is the addition-esterification of carboxylic acids to cyclic olefins. For example, the addition of saturated carboxylic acids to dicyclopentadiene, leading to starting esters for the flavor and fragrance industry [27]. 

Esterification. At room temperature, saturated carboxylic acids are selectively esterified with an alcohol in the presence of Amberlyst-15 resin. Alkenoic and aroic acids are left unreacted. Transesterification of alkyl formate to a dicarboxylic acid forming the monocarboxylic ester is catalyzed by Dowex-50WX2. ... 

Keywords Biodiesel Eleostearic acid Esterification by Amberlyst-15 Fuel properties Response surface methodology Tung oil... 

As tung oil has a high acid value (AV), the esterification using solid acid catalyst, Amberlyst-15, was employed to produce biodiesel more efficiently. Optimal condition of methanol and catalyst for the esterification was established by response surface methodology. The fuel properties of tung biodiesel produced from pretreated tung oil by alkali catalyst were analyzed. 

The solid acid catalyst, Amberlyst-15, was used for the esterification reaction of the free fatty acids of the tung oil because Amberlyst-15 showed good efficiency for the esterification of oleic acid with methanol [10]. 

The central composite design was used to determine the optimal conditions for the esterification of tung oil using Amberlyst-15. The independent variables were the molar equivalents of methanol to oil and the weight percent of Amberlyst-15 to oil. Experiment 1... 

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