Reactor online

Raghaven, K. V. (1992). Temperature Runaway in Fixed Bed Reactors Online and Offline Checks for Intrinsic Safety. Journal of Loss Prevention in the Process Industries 5, 3,153-59. 

REB (2010) Hydrogen separation and membrane reactors) [online], available http // www.rebresearch.com/H2perm2.htm,http //www.rebresearch.com/H2sol2.htm. 

Data used in this study were obtained on an isothermal fixed-bed reforming pilot plant. The reactor section was equipped with five sampling taps spaced along the length of the reactor. Online gas chromatograph analyses of the axial reformate san les provide composition profiles of 285 hydrocarbon conponents with increasing residence time through the catalyst bed. 

Anon., n.d. CANDU Reactors. [Online]. Available at http //www.eandn.org/eandu ieactors.html. [Accessed 18 March 2016]. 

Ethylene hydrogenation was carried out in a once-through flow reactor. The effluent gas mixture was analyzed with an online gas chromatograph (Hewlett-Packard HP 6890) equipped with an AI2O3 capillary column and a flame ionization detector. Testing conditions included Phydrogen = 200 Torr, Pethyiene = 40 Torr, catalyst mass of 10 to 20 mg and temperature varied from -50 to -25°C. 

The catal5fsts were tested for CO oxidation in a flow reactor using a 2.5 % CO in dry air mixture at a fixed flow rate of 200 seem. Thirty milligrams of the catalyst were used for each experimental run. The reaction was conducted at 298, 323, 373 and 473 K with 75 minutes duration at each temperature. The carbon monoxide conversion to carbon dioxide was monitored by an online gas chromatogr h equipped with a CTR-1 column and a thermal conductivity... 

Both the reactors are operated in batch, and the concentrations of components involved are measured online by electro-conductivity. Data interpretation is made by the kinetic equation of second order. The results obtained in the range of 25-45"C are given in Table 3. Again, the values for the rate constant measured in SCISR, ks, are S5 tematically higher than those in STR, ksr, by about 20%, and no significant difference betvi een the values for the active energy measured in SCISR and STR has been found. 

The catalytic reforming of CH4 by CO2 was carried out in a conventional fixed bed reactor system. Flow rates of reactants were controlled by mass flow controllers [Bronkhorst HI-TEC Co.]. The reactor, with an inner diameter of 0.007 m, was heated in an electric furnace. The reaction temperatoe was controlled by a PID temperature controller and was monitored by a separated thermocouple placed in the catalyst bed. The effluent gases were analyzed by an online GC [Hewlett Packard Co., HP-6890 Series II] equipped with a thermal conductivity detector (TCD) and carbosphere column (0.0032 m O.D. and 2.5 m length, 80/100 meshes), and identified by a GC/MS [Hewlett Packard Co., 5890/5971] equipped with an HP-1 capillary column (0.0002 m O.D. and 50 m length). 

Lu, H., Schmidt, M. A., Jensen, K. F., Photochemical reactions and online product detection in microfabricated reactors, in Matlosz, M., Ehrfeld, W., Baselt, j. P. (Eds.), Microreaction Technology - IMRET 5 Proc. 5th International Conference on Microreaction Technology, pp. 175-184, Springer-Verlag, Berlin (2001). 

Reaction detectors are a convenient means of performing online postcolumn derivatization in HPLC. The derivative reaction is performed after the separation of the sample by the column and prior to detection in a continuous reactor. The mobile phase flow is not interrupted during the analysis and reaction, although it may be augmented by the addition of a secondary solvent to aid the reaction or to conform to the requirements of the detector. Reaction detectors are finding increasing application for the analysis of trace components in complex matrices where both high detection sensitivity and selectivity are needed. Many suitable reaction techniques have been published for this purpose [641-650]. 

If the catalyst degrades (e.g. as a result of coke formation on the surface), then a fixed-bed device will have to be taken off-line to regenerate the catalyst. This can either mean shutting down the plant or using a standby reactor. If a standby reactor is to be used, two reactors are periodically switched, keeping one online while the other is taken offline to regenerate the catalyst. Several reactors might be used in this way to maintain an overall operation that is... 

Activities of the catalysts were measured on a microreactor. About 3 g of catalyst was charged into a reactor and heat-treated in nitrogen at reaction temperature. Acetic acid was added to the process and the reaction was initiated by switching nitrogen to ethylene. Reaction product analyses were performed by an online gas chromatograph equipped with a flame ionization detector (Perkin Elmer Auto System II). 

Inlet and outlet gases were analyzed online by a Micro GC equipped with four packed columns. The liquid organic and aqueous products were analyzed using an HP 5890 GC with capillary column DB-5 and an HP 5790 GC with Porapak Q packed column, respectively. The reactor wax withdrawn periodically was analyzed by a high-temperature HP5890 GC employing an alumina-clad column. 

After the activation period, the reactor temperature was decreased to 453 K, synthesis gas (H2 CO = 2 1) was introduced to the reactor, and the pressure was increased to 2.03 MPa (20.7 atm). The reactor temperature was increased to 493 K at a rate of 1 K/min, and the space velocity was maintained at 5 SL/h/gcat. The reaction products were continuously removed from the vapor space of the reactor and passed through two traps, a warm trap maintained at 373 K and a cold trap held at 273 K. The uncondensed vapor stream was reduced to atmospheric pressure through a letdown valve. The gas flow was measured using a wet test meter and analyzed by an online GC. The accumulated reactor liquid products were removed every 24 h by passing through a 2 pm sintered metal filter located below the liquid level in the CSTR. The conversions of CO and H2 were obtained by gas chromatography (GC) analysis (micro-GC equipped with thermal conductivity detectors) of the reactor exit gas mixture. The reaction products were collected in three traps maintained at different temperatures a hot trap (200°C), a warm trap (100°C), and a cold trap (0°C). The products were separated into different fractions (rewax, wax, oil, and aqueous) for quantification. However, the oil and wax fractions were mixed prior to GC analysis. 

In some applications, additional components acting as reactors for specific chemical pretreatment are incorporated within the flow manifold. Typical examples are ion-exchange microcolumns for preconcentration of the analyte or removal of interferences and redox reactors, which are used either to convert the analyte into a more suitable oxidation state or to produce online an unstable reagent. Typical examples of online pretreatment are given in Table 2. Apart from these sophisticated reactors, a simple and frequently used reactor is a delay coil (see also Fig. 4), which may be formed by knitting a segment of the transfer line. This coil allows slow CL reactions to proceed extensively and enter into the flow cell at the time required for maximum radiation. The position of the reactors within the manifold is either before or after the injection port depending on the application. 

Other studies in this specific area are also based on the catalytic effect of a variety of metal ions such as copper (II), cobalt (II), nickel (II), iron (III), and manganese (II) on the luminol-hydrogen peroxide reaction providing a rapid and efficient detection mode for these five ions, when an online CL detector is used before separation by CE [88], This contribution combines capillary ion analysis (CIA) and CL detection by means of a postcapillary reactor similar to the one originally developed by Rose and Jorgenson [80] and finally modified by Wu... 

In order to achieve results with close-to-conventional testing conditions, the parallel reactor setup for liquid-phase reaction must mimic the real process conditions of the later process as nicely as possible. The main efforts to be realized lie in the miniaturization and integrated construction of the parallel testing setup and the automation of process control combined with suitable online and offline analytical methodologies. 

Three Mile Island and Chernobyl occurred more than 20 years ago and the nuclear power freeze is beginning to thaw. High priced oil and natural gas make atomic energy appear cheap by comparison. Global-warming concerns are pushing a new interest in nuclear power. After a decade where no nuclear power plants came online in the United States, 31 new reactors are planned. 

Catalysts were tested for oxidations of carbon monoxide and toluene. The tests were carried out in a differential reactor shown in Fig. 12.7-1 and analyzed by an online gas chromatograph (HP 6890) equipped with thermal conductivity and flame ionization detectors. Gases including dry air and carbon monoxide were feed to the reactor by mass flow controllers, while the liquid reactant, toluene was delivered by a syringe pump. Thermocouple was used to monitor the catalyst temperature. Catalyst screening and optimization identified the best catalyst formulation with a conversion rate for carbon monoxide and toluene at room temperature of 1 and 0.25 mmolc g min1. Carbon monoxide and water were the only products of the reactions. 

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