Catalyst test reactor

The photocatalytic experiments were performed in a horizontal quartz tube which it have TiOi. Illumination was provided by 500 W mercury lamps, located above the horizontal quartz tube. The reactant was 0.1% (v/v) ethylene in air. In case of Photo-Catalyst test, reactor effluent samples were taken at 30 min intervals and analyzed by GC. The composition of hydrocarbons in the feed and product stream was analyzed by a Shimadzu GC14B (VZIO) gas chromatograph equipped with a flame ionization detector. In all case, steady state was reached within 3 h. 

Jensen gives several examples for his present highly integrated chip systems [101], including a gas-phase reactor, a liquid-phase reactor, a catalyst-testing reactor, and a packed-bed multi-phase reactor. In addition, he provides the vision of a multiple micro-reactor test station (see Section 1.5.5.2). 

The surface areas used in the catalyst test reactor are different for different catalyst geometries. Plate catalyst samples have a surface area of about 20cm and honeycomb types have a surface area of about lOOcm. ... 

Another versatile catalyst test reactor for the investigation of multiphase reactions is shown in Figure 13-7. In such reactors, rotational velocities in excess of 750 rpm ensure very good mass transfer between the catalyst, the gas bubbles, and the liquid, and an internal circulation is generated in the reactor [4]. 

Thus, benzaldehyde hydrogenation was tested imder practice-relevant conditions in a catalyst test reactor of simple design, and parameter smdies were carried out. The construction of the laboratory plant is shown schematically in Figure 13-17. Since we are dealing with an integral reactor, in spite of the relatively small amount of catalyst in the trickle-bed reactor, only comparitive measurements were carried out. Continuous hydrogenation of benzaldehyde in the solvents hexane and isopropanol ... 

Low YY et al (2001) Multichannel catalyst-testing reactor with microfluidic flow control. Chem big Tech 73(6) 661... 

Figure 7.7. PTA emission catalyst test reactor scheme.

Bosch and co-workers devised laboratory reactors to operate at high pressure and temperature in a recycle mode. These test reactors had the essential characteristics of potential industrial reactors and were used by Mittasch and co-workers to screen some 20,000 samples as candidate catalysts. The results led to the identification of an iron-containing mineral that is similar to today s industrial catalysts. The researchers recognized the need for porous catalytic materials and materials with more than one component, today identified as the support, the catalyticaHy active component, and the promoter. Today s technology for catalyst testing has become more efficient because much of the test equipment is automated, and the analysis of products and catalysts is much faster and more accurate. 

Catalyst testing and evaluation have been revolutionized by computers, automated test reactors, and analytical methods. With modem equipment, researchers can systematically prepare and screen many catalysts in a short time and efftciendy deterrnine, not only the initial catalytic activity and selectivity, but also the stabiUty and the appearance of trace products that may indicate some new catalytic properties worthy of further development. 

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. 

The experimental unit, shown on the previous page, is the simplest assembly that can be used for high-pressure kinetic studies and catalyst testing. The experimental method is measurement of the rate of reaction in a CSTR (Continuous Stirred Tank Reactor) by a steady-state method. 

Tests 2 and 3 were run in the same reactor as Test 1. In order to confirm the initial activity, the catalyst was started up without added sulfur. The catalyst picked up sulfur in both these tests and was deactivated even though no sulfur was added to the feed this indicates that sulfur remained in the reactor after Test 1. This is a common problem encountered when working with sulfur in laboratory test reactors. The sulfur reacts with the steel walls of the reactor. Then, even though sulfur is removed from the feed, sulfur evolves from the walls of the reactor and it is either picked up by the catalyst or it appears in the effluent from the reactor. With continuous addition of sulfur, the CO leakage continues to increase. 

In eqs. 1 and 2, ry M and rco2 denote the molar hourly production of each species per gram of catalyst while pt denotes the catalyst s bulk density (grams catalyst per reactor liter). Each of the catalysts from the Pd-Au-KOAc catalyst series was tested and evaluated under steady-state conditions in the fixed bed reactor under process conditions typical of vinyl acptata synthesis and the VAM STY and VAM SEL results are included as Table 1. 

The catalyst testing was carried out in a gas phase downflow stainless steel tubular reactor with on-line gas analysis using a Model 5890 Hewlett-Packard gas chromatograph (GC) equipped with heated in-line automated Valeo sampling valves and a CP-sD 5 or CP-sil 13 capillary WCOT colunm. GC/MS analyses of condensable products, especially with respect to O-isotopic distribution, was also carried out using a CP-sil 13 capillary column. For analysis of chiral compounds, a Chirasil-CD capillary fused silica column was employed. 

Figure 1.9 Hybrid, multi-scale micro-reactor plant for catalyst testing for propane steam reforming [15],...

One implication of micro reactors on chemical-process engineering concerns the shrinkage of the total system. This is exemplarily discussed for catalyst testing. 

For catalyst testing, conventional small tubular reactors are commonly employed today [2]. However, although the reactors are small, this is not the case for their environment. Large panels of complex fluidic handling manifolds, containment vessels, and extended analytical equipment encompass the tube reactors. Detection is often the bottleneck, since it is still performed in a serial fashion. To overcome this situation, there is the vision, ultimately, to develop PC-card-sized chip systems with integrated microfluidic, sensor, control, and reaction components [2]. The advantages are less space, reduced waste, and fewer utilities. 

A growing number of research groups are active in the field. The activity of reforming catalysts has been improved and a number of test reactors for fuel partial oxidation, reforming, water-gas shift, and selective oxidation reactions were described however, hardly any commercial micro-channel reformers have been reported. Obviously, the developments are still inhibited by a multitude of technical problems, before coming to commercialization. Concerning reformer developments with small-scale, but not micro-channel-based reformers, the first companies have been formed in the meantime (see, e.g., ) and reformers of large capacity for non-stationary household applications are on the market. 

Ajmera, S. K., Deiattre, C., Schmidt, M. A., Jensen, K. F., Microfabricated cross-flow chemical reactor for catalyst testing. Sens. Actuators 82, 2-3 (2002) 297-306. 

Hendershot, R.J., Lasko, S.S., Fellmann, M.-F. et al. (2003) A novel reactor system for high throughput catalyst testing under realistic conditions. Appl. Catal. A Gen., 254, 107. 

Van Santen [13] identifies three levels of research in catalysis. The macroscopic level is the world of reaction engineering, test reactors and catalyst beds. Questions concerning the catalyst deal with such aspects as activity per unit volume, mechanical strength and whether it should be used in the form of extrudates, spheres or loose powders. The mesoscopic level comprises kinetic studies, activity per unit surface area, and the relationship between the composition and structure of a catalyst and its... 

Figure 11.24 Simulation of the thermal behavior of a catalyst in a multitube test reactor. (AH > 100 kJ/mol, Tiri et 523 K, Treactor 523 K, porosity 80%, /.bed 3.0W/mK, GHSV 10000 h-1, reactor tube geometry 0.11 x 0.007 m).

The pyrolytic reforming reactor was a packed bed in a quartz tube reactor. Quartz was selected to reduce the effect of the reactor construction material on the hydrocarbon decomposition rate. ° The reactor was packed with 5.0 0.1 g of AC (Darco KB-B) or CB (BP2000) carbon-based catalyst. The reactor was heated electrically and operated at 850—950 °C, and the reactants had a residence time of 20—50 s, depending on the fuel. The reactor was tested with propane, natural gas, and gasoline as the fuels. Experiments showed that a flow of 80% hydrogen, with the remainder being methane, was produced for over 180 min of continuous operation.The carbon produced was fine particles that could be blown out... 

Tables 2.1 and 2.4 show the VGO-C feed quality properties and the test conditions of the Riser Simulator experiments. The three catalysts tested were the same ones used in the FFB reactor experiments. Temperature for the LZM catalyst was lower than for the other catalysts to reproduce typical conditions used for mid-distillate maximization in commercial units.

The tests were performed in a modified circulating ARCO pilot unit at Chalmers [18,19] with a North Sea atmospheric residue as feed. The reactor temperature was 500°C and the regenerator temperature was 700°C. Each of the catalyst tests were... 

Catalyst samples were prepared by extiTusion with 2058 Plow isothermic reactor with a fixed bed of a catalyst was employed for catalyst testings. Liquid reaction products were analyzed by GC on a column contained Inerton N Super with 558 Carbo-wax 20M. 

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