Conversion and temperature

By maintaining the first-stage reactor just beyond the phase inversion point, the dispersed rubber phase is relatively rich in dissolved styrene. As polymerization subsequently proceeds in the LFR s, the dissolved styrene will react to form either a graft copolymer with the rubber or a homopolymer. The latter will remain within the rubber droplet as a separate occluded phase. Achieving the first-stage reactor conversion and temperature by recycling a portion of the hot second reactor effluent may permit simplification of the first reactor temperature control system. 

First we tuned the simulation model using existing operation conditions. Product properties as well as conversion and temperature profile along the reactor axis closely coincided with the actual data after properly choosing the kinetic constants and other operation parameters. 

Equation 10.3.6, the reaction rate expression, and the design equation are sufficient to determine the temperature and composition of the fluid leaving the reactor if the heat transfer characteristics of the system are known. If it is necessary to know the reactor volume needed to obtain a specified conversion at a fixed input flow rate and specified heat transfer conditions, the energy balance equation can be solved to determine the temperature of the reactor contents. When this temperature is substituted into the rate expression, one can readily solve the design equation for the reactor volume. On the other hand, if a reactor of known volume is to be used, a determination of the exit conversion and temperature will require a simultaneous trial and error solution of the energy balance, the rate expression, and the design equation. 

Here, one may employ a higher temperature for the second-stage feed and still achieve the desired conversion level. The conversion and temperature profiles as calculated from equations A and B are given in Table 12.1.2. 

Conversion and Temperature Profiles for Packed Bed Reactor of Illustration 12.9... 

Part (b) After leaving the heat exchanger, the net product goes to storage through a pipeline with a volume of 2500 liters. Reaction continues adiabatically. Find the conversion and temperature entering storage. 

Initially, T0 = 300 and r0 = 2. Find the relation between time, conversion and temperature when the rate is kept constant up to 90% conversion. 

These arguments do not hold in a CSTR because the conversion and temperature jump discontinuously fiom X = 0, T = Tq to X, T in the reactor and at the exit. Trajectories are continuous curves for the PFTR but are only single points for the CSTR. We wiU examine this in more detail in the next chapter. 

The kinetic results are summarized in Table II. The autoxidation products in general are similar to those observed by Van Sickle at lower temperatures and conversions. Table III summarizes analyses made by Van Sickle at conditions approximating our levels of conversion and temperature. The polymeric dialkyl peroxides are included in the residue. 

The terms in Equation 1.2 are described in Nomenclature. The condition of constant heat capacity can be relaxed if accurate data is available for heat capacity as a function of both conversion and temperature. 

In Figure 5.8, the conversion and temperature profile in the reactor versus the distance from the reactor length for inlet CO concentration of 4000 ppm is given. 

Fig. 53. Simulation of transient NO to NOz conversion and temperature at DOC outlet during ESC (left) and ETC (right) test cycle, simulated N02/NOx ratio solid black line, temperature dashed gray line (Chatterjee et al., 2006). Reprinted with permission from SAE Paper 2006-01-0468 2006 SAE International.

Curves plotted from data obtained illustrating total isomer yield vs. conversion and temperatures that produced these conversions... 

Thermal dehydrochlorination of 1,2-dichloroethane188-190 272 273 takes place at temperatures above 450°C and at pressures about 25-30 atm. A gas-phase free-radical chain reaction with chlorine radical as the chain-transfer agent is operative. Careful purification of 1,2-dichloroethane is required to get high-purity vinyl chloride. Numerous byproducts and coke are produced in the process. The amount of these increases with increasing conversion and temperature. Conversion levels, therefore, are kept at about 50-60%. Vinyl chloride selectivities in the range of 93-96% are usually achieved. 

Morton and Rupert 209) have presented microstructure results for polybutadiene and polyisoprene as a function of conversion and temperature. (Tables 18 and 19). 

Volume versus conversion and temperature Vend = 1 to3 Figure 4.3... 

Conversion and temperature versus volume graphs for multiple [Pg.148]

A complete description of model of filling a rectangular mold and the subsequent solidification of an article was developed,47 and in this case a fountain effect near the stream front was included. The authors used the model to predict pressure increase during mold filling, and the distribution of the degree of conversion and temperature at both stages (filling and solidification). The results... 

In addition, it is necessary to use the equation for the dependence of viscosity on the degree of conversion and temperature ... 

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