Ethyl acetate, saponification

KINETICS OF ETHYL ACETATE SAPONIFICATION 12.3.1 Chemical reaction and experimental method... 

For further verification that the LIS promotes process kinetics, Wu et al. [181] studied comparatively the kinetics of ethyl acetate saponification in the submerged circulative impinging stream reactor (SCISR) and a stirred tank reactor (STR), respectively. The chemical reaction is represented by... 

In the ranges of the operating conditions tested, the overall crystal- growth rate coefficient of Na2HP04 measured in ISC, Vs. is higher systematically than that measured in FBC, Vu. by 15 to 20%, while the reaction rate constant of ethyl acetate saponification measured in the SCISR, Vs. is larger systematically than that measured in the STR, Vt> by about 20%. 

The regression of the data on the kinetics of ethyl acetate saponification in the range of reaction temperature from 25 to 45 °C yields the active energy in the... 

Indanyl)-phenol 16 was obtained by reacting p-methoxy-phenyl-acetic acid ethyl ester with benzylchloride to form a-benzyl-p-methoxyphenyl ethyl acetate, saponification into the acid, conversion of the acid with thionylchloride into the chloride, cyclization to 2-p-methoxy-phenyl-l-indanone, NaBH4 reduction to 2-p-methoxyphenyl-l-indanole, dehydration with p-toluene-sulphonic acid in toluene to 2-p-methoxyphenyl-indene, catalytic hydrogenation to 2-p-methoxyphenyl-indene, and treating the ether with HBr [Eq. (5)]. 

Figure 2.9 displays the equations describing the relationships between ethyl acetate concentration and time for the experiments shown in Figure 2.8. The top equation in Figure 2.9 is for an initial 0.1 mol/L ethyl acetate the middle equation is for an initial 0.05 mol/L ethyl acetate and, the bottom equation is for an initial 0.025 mol/L ethyl acetate. From these equations, we can calculate the initial reaction rate for ethyl acetate saponification. For 0.1 mol/L ethyl acetate, the equation is...

Our interest is in the initial rate of ethyl acetate saponification, which occurs at t = Therefore, setting t = 0 in the above equation gives us... 

With this information, we can calculate / Forward for ethyl acetate saponification at 22° C. The intercept for the reactions conducted at constant initial NaOH concentration is, from Figure 2.10... 

We have now determined the reaction order of each reactant for ethyl acetate saponification via two procedures one, with respect to initial reactant concentration the other, with respect to initial reaction time. We have a choice with regard to the latter procedure we can calculate the reaction rate using a central difference algorithm or we can generate a polynomial equation describing the change in reactant concentration as a function of time, then differentiate that polynomial to obtain the reaction rate. Table 2.4 presents the results for each of these procedures for ethyl acetate saponification. So— which reaction rate equation is correct The more appropriate question is which reaction rate equation is valid The most valid reaction rate equation is the one based on initial reactant concentrations. The reaction rate equations based on initial reaction time are approximations of it. The sets of equations will be similar but not necessarily the same since we determined each set via a different experimental procedure. 

Table 2.4 contains the rate constant for ethyl acetate saponification as determined by the latter three methods above. 

Ethyl acetate saponification is a much studied reaction. If we assume that Rp depends linearly on ethyl acetate concentration and linearly on NaOH concentration, i.e., if we follow the first procedure listed above, then we can write the above differential equation as... 

From which we calculate k. This method, the first one listed above, yields 8.3 L/mol min or 0.14L/mol s for the ethyl acetate saponification rate constant k As shown in Chapter 2, the initial time central difference method gives 8.3 L/mol min and the initial time polynomial method gives 8.8 L/mol min and the initial concentration method yields 3.8 L/mol min for the ethyl acetate saponification rate constant (see Table 2.4). 

Table 3.1 tabulates the Arrhenius slopes of each polynomial coefficient for ethyl acetate saponification and sucrose inversion. These... 

Figure 3.10 Volume dependency ofpolynomial coefficients of ethyl acetate saponification.

Figures 3.10 and 3.11 display polynomial coefficients as a function of reactor volume. Both figures demonstrate that polynomial coefficients are independent of reactor volume, where we define reactor volume as the liquid volume within the reactor. Figure 3.10 shows the polynomial coefficients for ethyl acetate saponification to be independent of reactor volume while Figure 3.11 shows the same result for sucrose inversion. ...

Figure 3.12 RPM dependence of polynomial coefficients for ethyl acetate saponification.

Itil)lc6.1 Initial Reactant ( onecntration and Initial Reaction Rate for Ethyl Acetate Saponification at Constant Sodium Hydroxide ( onecntration and ariable Ethyl Acetate Concentiation ... 

For easy presentation, take a typical second-order reaction the reaction of ethyl acetate saponification as an example ... 

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