Hydrolysis of methyl acetate

Ion exchange resin heads used as column packing Hydrolysis of methyl acetate t lichigami, J. Chem. Eng. Jap., 23,. 354 (1990)... 

Slotted plate for catalyst support designed with openings for vapor flow Ion exchanger fibers (reinforced ion exchange polymer) used as solid-acid catalyst None specified Hydrolysis of methyl acetate Evans and Stark, Eiir. Pat. Appl. EP 571,163 (1993) Hirata et al., Jap. Patent 05,212,290 (1993)... 

An instance of autocatalysis is the hydrolysis of methyl acetate, which is catalyzed by product acetic acid, A C. The rate equation may be... 

Hydrolysis of methyl acetate or its reverse, esterification of acetic acid... 

The liquid-phase hydrolysis of methyl acetate (A) to acetic acid and methyl alcohol is a reversible reaction (with rate constants kf and k as in equation 5.3-3). Results of an experiment carried out at a particular (constant) temperature in a BR in terms of the fraction hydrolyzed (/A) measured at various times (t), with cAo = 0.05 mol L-1 (no products present initially), are as follows (Coulson et al, 1982, p. 616) ... 

Two configurations of stirred-tank reactors are to be considered for carrying out the reversible hydrolysis of methyl acetate (A) to produce methanol (B) and acetic acid (C) at a particular temperature. Determine which of the following configurations results in the greater steady-state rate of production of methanol ... 

The hydrolysis of methyl acetate (A) in dilute aqueous solution to form methanol (B) and acetic acid (C) is to take place in a batch reactor operating isothermally. The reaction is reversible, pseudo-first-order with respect to acetate in the forward direction (kf = 1.82 X 10-4 s-1), and first-order with respect to each product species in the reverse direction (kr = 4.49 X10-4 L mol-1 S l). The feed contains only A in water, at a concentration of 0.050 mol L-1. Determine the size of the reactor required, if the rate of product formation is to be 100 mol h-1 on a continuing basis, the down-time per batch is 30 min, and the optimal fractional conversion (i.e., that which maximizes production) is obtained in each cycle. 

The rate of hydrolysis of methyl acetate is reversible and proceeds according to the equation... 

Data for the acid hydrolysis of methyl acetate (A) at 25°C CH3C02CH3 + H20 = CH3COOH + CH3OH... 

The hydrolysis of methyl acetate (A) is catalyzed by the reaction product acetic acid (B). In one experiment, when the initial concentration of acetate was 0.5 and that of the acid was 0.05 gmol/liter, 60% conversion was attained in one hour. Find the time at which the reaction velocity became a maximum and the value of this maximum. 

A similar reaction, namely the hydrolysis of methyl acetate,... 

Nil Ratan Dhar, Coefficient de temperature de reactions catalytiques (Paris These d Universite, 1916) "Catalysis, Pt. IV, Temperature Coefficients of Catalysed Reactions," JCS.Trans. Ill (1917) 707762 and The Chemical Action of Light (London Blackie and Son, 1931). And Alfred Lamble and William C. McCullagh Lewis, "Studies in Catalysis, Pt. I, Hydrolysis of Methyl Acetate, with a Theory of Homogeneous Catalysis," JCS.Trans. 105 (1914) 23302342 and W. C. McCullagh Lewis, "Studies in Catalysis, Pt. VII, Heat of Reaction, Equilibrium Constant, and Allied Quantities, from the Point of View of the Radiation Hypothesis," JCS.Trans. Ill (1917) 457469. 

Human exposure to 10,000 ppm for a short period of time resulted in eye, nose, and throat irritation, which persisted after cessation of exposure. In a man exposed to unmeasured concentrations, effects were general central nervous system depression, headaches, and dizziness, followed by blindness of both eyes caused by atrophy of the optic nerve. The toxic action on the optic nerve is possibly related to the presence of methanol after hydrolysis of methyl acetate. ... 

Figure 7 shows the results of methyl acetate carbonylation in the presence of water. Methanol and dimethyl ether were formed up to 250 C suggesting that hydrolysis of methyl acetate proceeded. With increasing reaction temperature, the yield of acetic acid increased remarkably, while those of methanol and dimethyl ether decreased gradually. Figure 8 shows the effects of partial pressures of methyl iodide, CO, and methyl acetate in the presence of water. The rate of acetic acid formation was 1.0 and 2.7 order with respect to methyl iodide and CO, respectively. Thus, the formation of acetic acid from methyl acetate is highly dependent on the partial pressure of CO. This suggests that acetic acid is formed by hydrolysis of acetic anhydride (Equation 6) which is formed from methyl acetate and CO rather than by direct hydrolysis of methyl acetate. 

The affinities of the acids deduced from their electrical conductivity, and their influence on the rates of hydrolysis of methyl acetate and of the inversion of cane sugar are nearly the same, as illustrated in Table XIV. 

Electrical conductivity. Hydrolysis of methyl acetate. Inversion of cane sugar. 

The electrical conductivity, the lowering of the f.p., the rate of hydrolysis of methyl acetate, and the inversion of cane-sugar, by W. Ostwald 2 have shown it to be one of the most powerful of the monobasic acids. It is therefore very active chemically and it usually behaves as an oxidizing agent, and is itself reduced. 

A quantitative assessment of the effects of head group bulk on, S k2 and E2 reactions in cationic micelles has been made.148 The kinetics of the acid-catalysed hydrolysis of methyl acetate in the presence of cationic, anionic, and non-ionic surfactants has been reported on.149 The alkaline hydrolysis of -butyl acetate with cetyltrimethylammonium bromide has also been investigated.150 The alkaline hydrolysis of aromatic and aliphatic ethyl esters in anionic and non-ionic surfactants has been studied.151 Specific salting-in effects that lead to striking substrate selectivity were observed for the hydrolysis of /j-nitrophenyl alkanoates (185 n = 2-16) catalysed by the 4-(dialkylamino)pyridine-fimctionalized polymer (186) in aqueous Tris buffer solution at pH 8 and 30 °C. The formation of a reactive catalyst-substrate complex, (185)-(186), seems to be promoted by the presence of tris(hydroxymethyl)methylammonium ion.152... 

The use of Eq. (5) to fit data recorded using a microcalorimeter was first demonstrated by Bakri (6), who studied the acid hydrolysis of methyl acetate in hydrochloric acid. In that experiment, 1 mmol of methyl acetate was added to 2mL of 1 N hydrochloric acid solution in a glass ampoule. The experimental data were fitted to Eq. (5) using a least squares analysis which gave k = 0.116 x 10-3 sec-1 and AH= 1.98 kJmol-1. In this paper, Bakri also shows how the method may be applied to both second-order, solution phase A+B x reactions and to flow calorimetry. 

Obviously, reactive distillation may lead to significant savings on energy. Hydrolysis of methyl acetate presents an industrial example of such energy savings. 

Fuchigami Y. Hydrolysis of methyl acetate in distillation column packed with reactive packing of ion exchange resin. J Chem Eng Japan 1990 23 354-358. 

A 1,10-phenanthroline-containing polyamine macrocycle (78) was designed to complex with Zn2+ ion and, because of the rigidity of the phenanthroline moiety, leave some free binding sites at the metal for ligands such as water, which easily depro-tonate to give stable hydroxo species. The hydrolysis of methyl acetate in the gas phase by such a monohydroxy-Zn(II) complex [Zn(78)(OH)]+ has been investigated by quantum mechanical procedures and some pathways delineated.78... 

Here we further examine the suitability of QM-SCRF methods in two chemical reactions the base-catalysed hydrolysis of methyl acetate in water, and the steric retardation of Sn2 reactions of chloride with ethyl and neopentyl chlorides in water. In the two cases the influence of the solvent is examined by using the MST version of the PCM model (see ref. [85] for a detailed description). 

Figure 3.6 Representation of the transition states TS1 (a) and TS2 (c), and the intermediate (b) formed in the base-catalysed hydrolysis of methyl acetate.

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