Reactor Berty

Figure 2.3.2 (Kraemer and deLasa 1988) shows this reactor. DeLasa suggested for Riser Simulator a Fluidized Recycle reactor that is essentially an upside down Berty reactor. Kraemer and DeLasa (1988) also described a method to simulate the riser of a fluid catalyst cracking unit in this reactor.

These reactors all work on very similar principles and will be discussed based on the example of the Berty reactor, of which more than 500 are in operation around the world. The Berty reactor shown in Figure 2.4.3 a has much empty volume and is laborious to open and close. Another version of the Berty reactor (made by Basic Technology, Inc.) is shown in Figure 2.4.3 b. This 2-inch model was developed for quick exploratory studies on small samples of catalysts. The maximum catalyst sample volume is 15... 

Carbcny and Berty reactors were made by Autoclave Engineers, Inc., Eric, Pennsylvania. 

The operational characteristics of the older Berty reactors are described in Berty (1974), and their use in catalyst testing in Berty (1979). Typical uses for ethylene oxide catalyst testing are described in Bhasin (1980). Internal recycle reactors are easy to run with minimum control or automation. 

Silva (1971) used the Berty reactor to execute exploratory measurements on vapor-phase hydrogenation of organic substrates that had little vapor pressure at room temperature. The substrate was measured by weight in a small ceramic boat and put on the catalyst screen beside a few particles of catalyst, also measured by weight. Then the stirring started, and the autoclave was heated to the reaction temperature. Finally the desired hydrogen pressure was applied suddenly and the reaction started. 

The RR developed by the author at UCC was the only one that had a high recycle rate with a reasonably known internal flow (Berty, 1969). This original reactor was named later after the author as the Berty Reactor . Over five hundred of these have been in use around the world over the last 30 years. The use of Berty reactors for ethylene oxide process improvement alone has resulted in 300 million pounds per year increase in production, without addition of new facilities (Mason, 1966). Similar improvements are possible with many other catalytic processes. In recent years a new blower design, a labyrinth seal between the blower and catalyst basket, and a better drive resulted in an even better reactor that has the registered trade name of ROTOBERTY . ... 

Table I. Product Compositions from the Catalysts ZSM-5 (11.1% Fe) and ZSM-5 (5.6% Fe, 4.5% Co), in a Berty Reactor, Showing the Influence of Cobalt Addition to the Catalyst.

Figure 5.4-19. Internally recycled reactor (Berty reactor).

In preliminary experiments the performance of the applied Micro-Berty reactor (Autoclave Engineers, Vr = 12 cm3 [18]) was tested. The catalyst mass introduced in this reactor was mcat= 2.1 g. In preliminary runs, by varying the stirring rate it... 

The results Illustrated by Figures 3 and 4 resemble those obtained in the Berty recycle reactor under similar conditions. The space-mean, time average rates for the fixed-bed reactor were only about 50% of those measured in the Berty reactor, because, of course the former reactor achieved conversions high enough for the back reaction to become important. The significance of these observations is that 1) CSTR and differential reactors, widely used for laboratory studies, seem to reflect performance improvements obtainable with fixed-bed, integral reactor which resemble commercial units, and 2) improvement from periodic operation are still observed even tfien reverse reactions become important. 

The authors are grateful for support in the form of an equipment grant for the Berty reactor from the National Science and Engineering Research Council of Canada, as well as for operating funds from the same source. Mr. Jain was supported by the University of Waterloo through a Dean of Engineering Scholarship. Catalyst was kindly provided by United Catalyst Inc., Louisville, Kentucky. 

Berty reactor High-pressure, high-temperature petroleum and chemical operations Can provide intense mixing and high transport rates Not useful for low-pressure operations Ease of variation of parameters can be limited... 

Fig. 7.18. CSTR with fixed bed and internal (Berty reactor) or external recirculation.

In recent years these problems have been largely overcome with the development of gas-phase continuous back-mixed reactors like the Berty reactor. This reactor recirculates the gas... 

The difficulties inherent to the external recycle reactor are avoided in an internal recycle reactor. Basically, an internal recycle reactor consists of a basket, in which a variable amount of catalyst can be placed, and an impeller for the internal circulation of the gas in the reactor. One of the most popular recycle reactors is the Berty reactor [29] shown in Figure 5.5. The Berty reactor has a magnetically driven blower and the gas from the turbine flows through a draft tube to the top of the catalyst bed. The flow rate through the bed can be calculated by measuring the pressure drop over the bed, if pressure taps on either side of the catalyst are available. For a catalyst to be studied in this reactor, the... 

Many authors have proposed reactors with similar basic principles. The best known are those of Garanin et al. [44], Livbjerg and Villadsen [45] and new versions of Berty reactor [34]. Variants of internal recycling reactors have also been proposed by Bennett et al. [43] who tried to decrease the ratio of reactor volume to catalyst volume. In this arrangement the amount of reactant adsorbed increases compared to that in the gas space as a result the dynamics of the adsorption - desorption processes can be detected through the gas phase measurements. 

Referring to Figure 3.5.2, the Carberry reactor contains paddles in which the catalyst is mounted and the paddles are rapidly rotated via connection to a control shaft in order to obtain good mixing between the gas phase and the catalyst. A Berty reactor consists of a stationary bed of catalyst that is contacted via circulation of the gas phase by impeller blades. The quality of mixing in this type of configuration... 

In Section 3.5 recycle reactors and particularly a Berty reactor were described. At high impeller rotation speed, a Berty reactor should behave as a CSTR. Below are plotted the dimensionless exit concentrations, that is, C(t)/C°, of cis-2-butene from a Berty reactor containing alumina catalyst pellets that is operated at 4 atm pressure and 2000 rpm impeller rotation speed at temperatures of 298 K and 427 K. At these temperatures, the cis-2-butene is not isomerized over the catalyst pellets. At t = 0, the feed stream containing 2 vol % cis-2-butene in helium is switched to a stream of pure helium at the same total flow rate. Reaction rates for the isomerization of cis-2-butene into 1-butene and trans-2-butene are to be measured at higher temperatures in this reactor configuration. Can the CSTR material balance be used to ascertain the rate data ... 

Figure 8.2.3 Dimensionless concentration (C/C ) of cis-2-butene in exit stream of Berty reactor as a function of time. See Example 8.2.3 for additional details.

Referring to Example 8.2.3, compute and plot the dimensionless exit concentration from the Berty reactor as a function of time for decreasing internal recycle ratio to the limit of PER behavior. 

Tank reactors for solid-catalyzed gaseous or liquid reactions are seen much less frequently than tubular reactors because of the difficulty in separating the phases and in agitating a fluid phase in the presence of solid particles. One type of CSTR used to study catalytic reactions is the spinning basket reactor, which has the catalyst embedded in the blades of the spinning agitator. Another is the Berty reactor, which uses an internal recycle stream to achieve perfectly mixed behavior." These reactors (see Chapter 5) are frequently used in industry to evaluate reaction mechanisms and determine reaction kinetics. 

Comparison of the data in Tables 1-3 for catalysts tested at 215 (with no loss of activity) and 248°C (with significant loss of activity) respectively indicates that deactivation of the iron catalysts in this study is qualitatively associated with (1) the transformation of high-activity -carbide to the less active e -carbide and (2) the formation of graphitic carbons (8, and 82) in the form of films or layers. While we attempted as part of this study to find a quantitative relationship between different carbon forms and the extent of deactivation of monolithic iron catalysts during FT synthesis at 10 atm in a Berty reactor, we were unsuccessful. The major problem was exposure of the spent... 

Because of the wide range of catalyst operation conditions, it is to be expected that a variety of kinetic regimes will occur during the use of the catalyst. This is exemplified in the Arrhenius diagram for the eqs 13 and 11 measured in a Berty reactor with a monolithic catalyst (Figs. 46 and 47) [36]. 

Figure 46. Arrhenius diagram for eq 13, recorded in a Berty reactor experiment with a fresh three-way catalyst (monolith catalyst with 62cellscm partial pressure CO 0.005 bar, partial pressure NO 0.005 bar, balance N2 Pt 1.1 g T, Rh 0.2 g I" ). Reprinted from ref [36] with kind permission of Elsevier Seience.

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