Batch reactor sampled

From diese various estimates, die total batch cycle time t(, is used in batch reactor design to determine die productivity of die reactor. Batch reactors are used in operations dial are small and when multiproducts are required. Pilot plant trials for sales samples in a new market development are carried out in batch reactors. Use of batch reactors can be seen in pharmaceutical, fine chemicals, biochemical, and dye industries. This is because multi-product, changeable demand often requues a single unit to be used in various production campaigns. However, batch reactors are seldom employed on an industrial scale for gas phase reactions. This is due to die limited quantity produced, aldiough batch reactors can be readily employed for kinetic studies of gas phase reactions. Figure 5-4 illustrates die performance equations for batch reactors. 

The catalytic degradation of PS was carried out in a semi-batch reactor where nitrogen is continuously passed with a flow rate of 30 mL/min. A mixture of 3.0 g of PS and 0.3 g of the catalyst was loaded inside a Pyrex vessel of 30 mL and heated at a rate of 30 C/min up to the desired temperature. The distillate from the reactor was collected in a cold trap(-10 °C) over a period of 2 h. The degradation of the plastic gave off gases, liquids and residues. The residue means the carbonaceous compounds remaining in the reactor and deposited on the wall of the reactor. The condensed liquid samples were analyzed by a GC (HP6890) with a capillary column (HP-IMS). 

Figure 1 Comparison of Xyhtol Conversion versus Temperature, 300cc Batch Reactor, 8,300kPa H2, 4-Hour Sample.

Selected conditions and results are shown in Table 2 that are representative of the catalyst performance. Continuous testing of the Ni/Re catalyst compared favorably with the baseline data generated for this catalyst in the batch reactor screening. At 200°C, the overall activity of the catalyst appeared slightly higher in the continuous reactor, achieving 94% conversion at a weight hourly space velocity of 2.5hr 1 (g xylitol/g catalyst/h) and 200°C compared to 88% conversion at an equivalent exposure in the batch reactor of 2.1 hr"1 (g xylitol/g catalyst/h) achieved at the 4 hour sample at 200°C. 

All reactions involving lactic acids were performed in 300 mL Parr Autoclave batch reactor. All reagents, including the resin catalyst, were charged into the reactor and heated up to the desired reaction temperature. Stirring was commenced once the desired temperature was reached this was noted as zero reaction time. Reaction sample were withdrawn periodically over the course of reaction and analysed for ester, water and alcohol using a Varian 3700 gas chromatograph with a thermal conductivity detector (TCD) and a stainless steel... 

A common laboratory device is a batch reactor, a nonflow type of reactor. As such, it is a closed vessel, and may be rigid (i.e., of constant volume) as well. Sample-taking or continuous monitoring may be used an alternative to the former is to divide the reacting system into several portions (aliquots), and then to analyze the aliquots at different times. Regardless of which of these sampling methods is used, the rate is determined indirectly from the property measured as a function of time. In Chapter 3, various ways of converting these direct measurements of a property into measures of rate are discussed in connection with the development of the rate law. 

The hydrolysis of methyl bromide (CffiBr) in dilute aqueous solution may be followed by titrating samples with AgNCfy The volumes of AgNC>3 solution (V) required for 10 cm3 samples at 330 K in a particular experiment in a constant-volume batch reactor were as follows... 

In terms of cost and versatility the batch reactor is the unit of choice. One disadvantage is the need for frequent sampling or monitoring of the performance, although instrumentation can be provided at moderate cost nowadays. The residence time can be varied over a wide range and many different reactions can be handled at different times. The quality of mixing and heat transfer may not be easy to relate to those in an eventual commercial unit. 

Sequences. See also Hammersley sequence sampling (HSS) Latin hypercube entries Sobol sequence quasi-Monte Carlo, 26 1011, 1013 quasirandom, 26 1016, 1036, 1048 Sequence tagged sites (STS), 12 513, 515 Sequencing batch reactor (SBR)... 

Although quantification of the elements present in the y spectrum can in theory be achieved from first principles using the equation given above, in practice uncertainties in the neutron capture cross-section and variations in the neutron flux within the reactor mean that it is better to use standards. These standards must be included in each batch of samples irradiated in order to account for variations in neutron flux inside the reactor. For analysis of minor and trace elements calibration is easier than with other analytical methods provided that the major element composition remains reasonably constant, as the y ray intensity is proportional to concentration over a very wide range of concentrations. However, for analysis of major elements, e.g., silver in silver coins, the relationship between intensity and concentration is more complex, due to progressive absorption of neutrons as they pass through the specimen. In such cases y ray intensity will also depend on the thickness of the sample and therefore specialized calibration methods are required (Tite 1972 277). 

The homogeneous batch conversion system is frequently applied in fundamental research on the thermochemical processes associated with the fuel-bed combustion [16,31,33,38,40,41,42]. Figure 33 shows an experimental batch reactor for temperature and gas sample measurements inside and over the fuel bed [40]. 

Aldol condensation of acetone is a well-known base-catalyzed reaction, and barium hydroxide is one of the catalysts for this reaction mentioned in textbooks. A family of barium hydroxide samples hydrated to various degress determined by the calcination temperature (473, 573, 873, and 973 K) of the starting commercial Ba(OH)2 8H2O were reported to be active as basic catalysts for acetone aldol condensation (282,286). The reaction was carried out in a batch reactor equipped with a Soxhlet extractor, where the catalyst was placed. The results show that Ba(OH)2 8H2O is less active than any of the other activated Ba(HO)2 samples, and the Ba(OH)2 calcined at 473 K was the most active and selective catalyst for formation of diacetone alcohol, achieving nearly 58% acetone conversion after 8h at 367 K in a batch reactor. When the reaction temperature was increased to 385 K, 78% acetone conversion with 92% selectivity to diacetone alcohol was obtained after 8h. The yield of diacetone alcohol was similar to that described in the literature in applications with commercial barium hydroxide, but this catalyst required longer reaction times (72-120 h) (287). No deactivation of the catalyst was observed in the process, and it could be used at least 9 times without loss of activity. 

Fig. 9.10-10. Schematic diagram of prototype Fig. 9.10-11 Detail of a sample container, batch apparatus. Fc, filter R, condenser A, PI, pressure indicator TI, temperature accumulator Pco2, pump W, heat exchanger indicator TC, temperature controller E1, E2, batch reactors (adapted from [29]) (adapted from [29])...

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