Solution Reactors

Figure A3.14.12. The first experimental observation of a Turing pattern in a gel strip reactor. Solutions containing separate components of the CIMA/CDIMA reaction are flowed along each edge of the strip and a spatial pattern along the horizontal axis develops for a range of experimental conditions. (Reprinted with pennission from [38], The American Physical Society.)...

Experiments were performed in tlie SIMULAR calorimeter using the power compensation method of calorimetry (note that it can also be used in the heat flow mode). In this case, the jacket temperature was held at conditions, which always maintain a temperature difference ( 20°C) below the reactor solution. A calibration heater was used to... 

For purposes of simulation and illustration we have chosen a batch reactor, solution polymerization of methylmethacrylate (MMA). Kinetic data were taken from Schmidt and Ray (1981) and thermodynamic data from Bywater (1955). We do not here consider the influence of diffusion control on the termination or other rate processes because such effects may be small when in a solution which is siifHciently dilute or when the polymer is of low molecular weight. 

Stainless steel microelectrodes were prepared by sheathing 100-pm diameter stainless steel wire in glass. Tips were polished on a precision diamond wheel. Electrode response to variation in cathodic depolarizer concentration was confirmed by exposure to solution containing up to 6 mM HjOj. The increase in for the electrode was comparable to the change observed for sample coupons exposed to the same H2O2 concentrations. The electrode was conditioned by exposure to the influent reactor solution for several hours before measuring E, within the biofouling deposits. 

Chapter 10 Choosing the Right Kind of Reactor SOLUTION... 

With two electrocatalytic steps in series, the concentration of the intermediate B (Eq. 70) goes through a maximum with time (or space-time for a flow reactor). Solution of the kinetic equations for each species (60) yields for the simple case of first-order reactions... 

Zasoski and Burau (1978) type batch reactor solution/soil ratios are typically on the order of 1(X) to 1, whereas in flow type reactors the ratio is typically less than 1 to 1. Narrow solution/soil ratios are sometimes used in simple centrifuge tube batch reactors where ratios from 1 1 to 10 1 are often used. I iii ihcrmore, in flow reactors the solid phase will be reacted with a greater mass of solute (concentration x flow velocity x time) than in batch reac-luis (concentration x volume). 

Hand, D.W., J.C. Crittenden, and W.E. Thacker. 1981. User oriented solutions to the homogeneous surface diffusion model Batch reactor solutions. Proc. 54th Annual Conf, Water Pollution Control Federation, Detroit, ML 4-9 Oct. 1981. Water Pollution Control Federation, Alexandria, VA. 

Analytical solutions can often be found (see, e.g., Levenspiel 1999 Doraiswamy 2001). These are for batch reactors (also applicable to plug-flow reactors). Solutions for mixed-flow reactors (see Section 11.2.7.2) will be different. 

The reactor held one liter of 0.1 M CaCl2 solution. Buffers were added in nominal concentrations as needed. The pH was adjusted to the desired value by adding HC1 or NaOH. The experiment was initiated by addition of 0.5 g of Fisher Reagent CaC03 (precipitated calcite). In runs with sulfite the reactor solution was analyzed by iodimetric titration before and after the experiment. 

In a typical experiment, 50 mg of Pt/Ti02/Ru02 was suspended in 25 mL of doubly distilled water which had been made 0.001 M in K[Ru(HEDTA)C1] 2H20, and the mixture was irradiated at 390 nm by a 250-W xenon lamp. Control experiments were performed in the absence of light, under argon, and in the absence of the ruthenium complex. Concentration of N03 was determined colorimetrically in the reactor solution by means of sulfanilic acid and 1-naphthylamine in the presence of zinc dust [112], Concentration of NOJ also was tested for but was found only in trace amounts. 

Both anatase and rutile were tested in separate experiments. When anatase was irradiated in the presence of the ruthenium complex, after 6 h the reactor solution was found to have a concentration of 6OO//MNO3 (15jtmol). In the absence of the ruthenium complex the yield was 117jtMNOj (2.93pmol). When rutile was used, the corresponding yields were 20.4 /jMNOj (0.51 jimol) and 4.0pMNO3 (0.1/tmol) in the presence... 

A mass of 0.200g of a putative catalyst was suspended in 300mL of deionized water in an immersion-well photochemical reactor under a slow stream of N2. The mixture was irradiated by a 400-W medium-pressure Hg lamp which produced more than 5 x 1019 photons per second. Control experiments under argon or without irradiation were performed. At the end of the irradiation, lOmL of 0.10M NaOH was added to the reaction flask. The contents were distilled into a receiving flask which contained 10 mL of HC1 and analyzed for NH3 by the indophenol method. Then 10 mL of the reactor solution was centrifuged and analyzed for N03 by Cd reduction followed by colorimetric analysis by the azo-dye method. 

Example Reactor Solution using Extent of Reaction and the DOF... 

In order to construct candidate regions using two-dimensional sub-constructions, variations of the familiar reactor equations are needed to construct PFR trajectories and CSTR loci that are maintained within a two-dimensional plane. Rooney et al. (2000) refer to these reactors as iso-compositional reactors. Solutions resulting fi-om iso-compositional reactors produce concentrations that lie entirely in a two-dimensional plane in R". There is, in fact, no difference in form between the iso-compositional reactor equation belonging to an iso-compositional CSTR (iCSTR)... 

The time rate of change of Ca concentration in the reactor solution is the derivative of Eq. (4.49). 

The Teflon seal joint (Fisher Scientific catalog number 14-513-100) consists a Teflon bearing with an exterior 24/40 taper, an 0-ring, and an adapter chuck. The sq>tumed side neck carries a needle-stemmed spoon that can be lowered into the reactor solution to unload the catalyst it carries. The other side neck is connected through a three-way valve to a gas tank and a constant-pressure manometric unit. The gas tank supplies the gaseous reactant while the manometric unit provides a convenient and sensitive method for monitoring the synthesis reaction by means of the gas uptake. The manometric unit (4-6) consists of two mobile arms of equal-diameter burets attached to an adjustable pulley system that is actuated by two... 

Gas-phase operation often uses premixed gases, which have to be heated to the reaction temperature. Owing to the faster reactions for gas-phase processes, typically being on the second scale, micro heat exchangers are proper reactor solutions [9]. 

Some generic flow sheets comprising the reactor solutions in Sections 14.3.1 and 14.3.2 for liquid-phase homogeneous reactions are given in [8] (see Figure 14.1). 

Since the principles of electrochemical biosensors and their application to process control in bioreactors will be broadly discussed in chapter 6 of this volume (sections 2 and 5), only a few remarks need to be said about this topic. Information up to 1990 can be found in [145-147] and in numerous citations comprised in that text. Our attention will be restricted mainly to voltammetric oxygen sensors used to control fermentation reactors. Inasmuch as the sensor has to be located immediately in the reactor solution, the following specifications should be respected ... 

The ABV reactor core is of a unified design (see Fig. V-2) similar core has been developed and qualified for the pilot nuclear cogeneration plant with the KLT-40S reactors. Solutions developed for the ice-breaker reactor cores and used in the ABV core are the following ... 

CHAPTERS BATCH REACTORS Solution. Once again,... 

CHAPTER 9 CONTINUOUS STIRRED TANK REACTORS Solution. 

CHAPTER 9 CONTINUOUS STIRRED TANK REACTORS Solution. Based on the example statement,... 

The authors took advantage of the amphiphiUc character of the copolymers synthesized to introduce a novel approach, consisting in the automatic, continuous withdrawal and dilution of the reactor solution with different solvents, in order to simultaneously measme different properties. This was first time when simultaneous polymer characterization in organic and aqueous environments, performed as the polymer is produced, was reported. 

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