Stoichiometric table batch

The complete stoichiometric table for the reaction shown in Equation (2-2) taking place in a batch reactor is presented in Table 3-2. 

The form of the stoichiometric table for a continuous-flow system (see Figure 3-2) is virtually identical to that for a batch system (Table 3-2) except that we replace by and by (Table 3-3). Taking A as the basis, divide Equation (2-1) through by Ihe stoichiometric coefficient of A to obtain... 

Overview. In Chapter 2, we showed that if we had the rate of reaction as a function of conversion, = /(X), we could calculate reactor volumes necessary to achieve a specified conversion for flow systems and the time to achieve a given conversion in a batch system. Unfortunately, one is seldom, if ever, given = yiX) directly from raw data. Not to fear, in this chapter we will show how to obtain the rate of reaction as a function of conversion. This relationship between reaction rate and conversion will be obtained in two steps. In Step 1, Part 1 of this chapter, we define the rate law, which relates the rate of reaction to the concentrations of the reacting species and to temperature. In Step 2, Part 2 of this chapter, we define concentrations for fiow and batch systems and develop a stoichiometric table so that one can write concentrations as a function of conversion. Combining Steps 1 and 2, we see that one can then write the rate as a function conversion and use the techniques in Chapter 2 to design reaction systems. 

Because this is a liquid phase reaction, the stoichiometric table will be the he same whether the leactton is carried out in either a batch or flow reactor. Na/V = NVV = Ca... 

In Step 2, described in Chapter 4, we define concentrations for flow and batch systems and develop a stoichiometric table so that one can write concentrations as a function of conversion. 

For batch systems the reactor is rigid, so Y = Vq and one then uses the stoichiometric table to express concentration as a function of conversion Ca a o aoO... 

Set up a stoichiometric table with ammonia as your basis of calculation. Express the concentration. C for each species as functions of conversion for a constant-volume batch reactor. Express the total pressure as a function of X. 

Let s begin by relating Nsa and Caa to Csa- This requires a little bookkeeping, for which we will use a stoichiometric table. To constract die stoichiometric table for a batch reactor, we list all of the species in die reactor in the far-left column, as shown in Table 4-1. The number of moles of each species at zero time, i.e., at the time the reaction starts, are listed in the next column. FinaUy, in the diird column, die number of moles of each species at some arbitrary time t are listed. In filling in the third column, the stoichiometry of the reaction is used, i ., for every mole of S A diat is consumed, one mole of AA is consumed, one mole of acetic acid (HOAc) is formed, and one mole of acetylsalicylic acid (ASA) is formed. 

Table 4-4 Stoichiometric Table for Reaction (4-A) Using the Whole Batch Reactor as a Control Wilume and Using Na as the Composition Variable...

The concentration of one particular species, usually the limiting reactant, is a very convenient variable to use for constant-volume (constant-density) systems. Note that Eqn. (4-7) could have been obtained by substituting the rate equation, Eqn. (4-5), into the design equation for a constant-volume batch reactor, Eqn. (3-8). However, the stoichiometric table still would have been required to relate the various concentrations in the rate equation. 

First, a stoichiometric table will be constructed to help with the molecular bookkeeping. Using the stoichiometric table, the variables Ca, Na, and V can be written as functions of xa- Finally, the design equation for an ideal batch reactor can be written and integrated to give the desired relationship between xa and t. If xa is known, the complete composition of die gas mixture can be calculated using the relationships in the stoichiometric table. 

First, set up a stoichiometric table (Table 4-11). Rather than working with moles perse, as in the case of batch reactors, stoichiometric tables for steady-state flow reactors should be constmcted in terms of molar flow rates. For a CSTR, the second column contains the inlet molar flow rates and the third column contains the molar flow rates in the reactor effluent. 

As noted in the discussion of ideal batch reactors, since the density is constant, we could have begun this problem by constructing a stoichiometric table based on concentration. 

You will be retrieving information on heats of formation from reference tables and data bases. The values in the tables have been reconciled from innumerable experiments. To determine the values of the standard heats (enthalpies) of forniation, the experimenter usually selects either a simple flow process without kinetic energy, potential energy, or work effects (a flow calorimeter), or a simple batch process (a bomb calorimeter), in which to conduct the reaction. Consider an experiment in a flow process under standard state conditions in which the experimental arrangement is such that the summation of sensible heat terms on the right-hand side of Eq. (4.33) is zero and no work is done. The steady-state (no accumulation term) version of Eq. (4.24a) for stoichiometric quantities of reactants and products reduces to... 

Table 1.2 summarizes the design equations for elementary reactions in ideal reactors. Note that component A is the only component or else is the stoichiometrically limiting component. Thus a = alao for batch reactions and a = afor flow reactors and Ya = a in both cases. For the case of a second-order reaction with two reactants, the stoichiometric ratio is also needed ... 

However, for AA and BB systems, like those shown in Table 7.1, stoichiometric imbalance can occur, with serious consequences for the polymerization. The molar ratio of the two types of functional end-groups (A and B) that are available for polymerization is determined by the initial molar ratio of the two monomers in a batch reactor, and by any monomers or oligomers that might escape from the reacting mixture during the polymerization. Note that escape of volatile monomers with the resulting influence on the ratio of functional groups is a serious practical problem for some industrial polymerizations that use volatile monomers (e.g., HMD in nylon 6,6 production and diphenyl carbonate in polycarbonate production). 

Table IX gives the recipe used for these pol3nnerizations. The polybutyl acrylate seed latex was prepared by heating the ingredients for 24 hours at 70° the styrene, water, and potassium persulfate were then added and polymerized for another 8 hours at 70°. Three methods of adding the styrene monomer were used in the second-stage polymerization (i) batch polymerization (ii) equilibrium swelling of the seed latex particles followed by batch pol3nneriza-tion (iii) starved semi-continuous pol3nnerization. The particle growth was essentially stoichiometric, i.e., no new particles were initiated. All three latexes formed transparent continuous films upon drying, whereas a 50 50 mixture of polybutyl acrylate and...

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