Stoichiometry reactor volume

It is also interesting to compare the conversions versus reactor volumes for these stoichiometries, and these are shown in Figure 3-6. 

Determine the conversion for an isothermal batch reactor using the stoichiometry of Example 5-1 and the same values of initial concentrations of A, B, C, and D in a reactor volume of 1 liter operating for 4 minutes. The rate constant is k = 105[(liter)2/(gmol2 min)]. 

A chemical reaction with stoichiometry A — products is said to follow an n -order rate law if A is consumed at a rale proportional to the nth power of its concentration in the reaction mixture. If is the rale of consumption of A per unit reactor volume, then... 

This equation is integrated numerically to determine the reactor volume that corresponds to 8% conversion of CO. However, this task cannot be accomplished until one employs kinetics, thermodynamics, and stoichiometry to express the rate law in terms of temperature, pressure, and conversion. Temperature can also be expressed in terms of conversion upon consideration of the thermal energy balance at high-heat-transfer Peclet numbers. 

Assuming a stoichiometry R for a first-order gas reaction, we ealeulate the size of plug flow reaetor needed to achieve a required conversion of 99% of pure A feed to be 32 liters. In fact, however, the reaction stoichiometry is A 3R. With this eorreeted stoichiometry, what is the required reactor volume ... 

The designer should be aware that there is a critical reactor volume, which generally corresponds to a bifurcation point of the mass balance equations. For stable operation the reactor should be larger than this critical value. As example, for essentially first-order reaction with pure product and recycle, the feasibility condition is simply Da>. The definition of the plant Damkohler number includes reactor volume, reaction kinetics and fresh reactant feed flow rate. Similar expressions hold for more complex stoichiometry. 

Since the volume depends on conversion or time in a constant pressure batch reactor, consider the mole balance in relation to the fractional conversion X. From the stoichiometry. 

Example 7.4 The following data have been obtained in a constant-volume, isothermal reactor for a reaction with known stoichiometry A B - - C. The initial concentration of component A was 2200 mol/m. No B or C was charged to the reactor. 

The following data were collected in an isothermal, constant-volume batch reactor. The stoichiometry is known and the material balance has been closed. The reactions are A B and A C. Assume they are elementary. Determine the rate constants kj and kn-... 

A constant volume batch reactor is used to convert reactant. A, to product, B, via an endothermic reaction, with simple stoichiometry, A —> B. The reaction kinetics are second-order with respect to A, thus... 

The liquid phase hydrolysis reaction of acetic anhydride to form acetic acid is carried out in a constant volume, adiabatic batch reactor. The reaction is exothermic with the following stoichiometry... 

The reaction system, 2A = B = > C, has been studied in a constant volume, batch reactor with the tabulated results. Assuming the orders conform to the stoichiometry, find the specific rates. 

This kind of reactor can be used for isothermal constant pressure operations, of reactions having a single stoichiometry. For such systems the volume is linearly related to the conversion, or... 

At 100°C pure gaseous A reacts away with stoichiometry 2A a constant volume batch reactor as follows ... 

The reaction has a stoichiometry of 2.0 (or 3.0 if carbonates are used, since the alkyl- or arylcarbonic acid instantly decarboxylates). Thus, if the reaction is studied under constant volume conditions, the pressure will double during the reaction. If a pressure-sensitive device is built into the wall of the reactor, then the progress of the reaction can be monitored. 

In most industrially relevant reacting systems, one main reaction typically makes the desired products and several side reactions make byproducts. The specific rate of production or consumption of a particular component in such a reaction set depends upon the stoichiometry and the rates. For example, assume that the main reaction for making vinyl acetate, Eq. (4.4.1, proceeds with a rate r< (mol/L s) and that the side reaction, Eq. (4.8), proceeds with rate r2 (mol/L s). Then the net consumption of ethylene is (-l)r1 - (-1 )r2 (mol/L s). Similarly, the net consumption of oxygen is (-0.5)fi + (— 3)r2, and the net production of water is (l)r-, + (2)ra. For a given chemistry (stoichiometry), our ability to control the production or consumption of any one component in the reactor is thus limited to how well we can influence the various rates. This boils down to manipulating the reactor temperature and/ or the concentrations of the dominant components. Occasionally, the reaction volume for liquid-phase reactions or the pressure for gas-phase reactions can also be manipulated for overall production control. These are the fundamentals of reactor control. 

A liquid-phase chemical reaction with stoichiometry A B takes place in a semibatch reactor. The rate of consumption of A per unit volume of the reactor contents is given by the first-order rate expression (see Problem 11.14)... 

From stoichiometry for a constant-volume batch reactor, we obtain... 

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