Reactor effluent sampling

There are several advantages and disadvantages to reactor effluent sampling ... 

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. 

Off-gas analyses were done by mass spectrometry and reactor effluent samples were analyzed by glc. Most of the glc work was done with an 8-foot 1/4-inch OD column containing 10% SE-30 on acid washed Chromsorb W. However, the separation of n-propyl-benzene from cumene had to be done with a dual 3/16-inch copper column consisting of a 12-foot section having 10% Bentone 34 and 10% Dow Corning silicone gum 550 on 60-80 mesh acid washed Chromsorb W and a 6-foot section containing 20% Apiezon L on 60-80 mesh acid washed Chromsorb P. 

Deposit formation in the reactor recycle cup is undesired due to potential plugging of catalyst distribution, which could lead to an uneven distribution of hydrogen in the ebullated catalyst bed. Analyses of recycle cup deposit and reactor effluent samples provide insight as to the mechanism(s) that contributes to recycle cup fouling. 

Flocculation Point. Figure 4 shows that the flocculation point of a reactor effluent sample (cracked atmospheric bottom) is much lower than that of the reactor feed. Generally, the flocculation point decreases as the amount of solids in the sample increases. This has been confirmed by the Shell Hot Filtration Test IP/375/ASTM 4870 procedure. 

The second technique involves direct sampling of the reactor effluent (Figure 5-2). In this technique, a sample of reactor effluent is collected in an aluminized polyester bag for separation and analysis. 

The feed flow rates and the reactor and bath temperatures were monitored at five minute intervals. After five to six residence times, two samples of the reactor effluent were collected in 50 ml Erlenmeyer flasks containing approximately 20 ml of benzene saturated with water. Sufficient polymer solution was collected to give a 3.0 weight percent polymer solution. The samples were... 

An essential method used in this work is quick ampoule sampling of volatiles.8-9 Small samples of the gaseous reactor effluent (e.g., 1 ml) are recovered in glass ampoules for later analysis. The capillary end of the evacuated ampoule is inserted into the product flow. The capillary tip is broken and the ampoule filled... 

Senkan et al. [34] introduced REMPI analysis technique as a Stage I tool and exemplified its applicability with the example of a dehydrogenation reaction. The principle of this analysis method is based on sample ionization via laser light and subsequent detection of the ionized reactor effluent at dedicated electrodes at the reactor exit. Owing to a number of limitations connected with the analysis technique, it has to be considered of restricted applicability. 

Pilot-Scale Reactor. Anaerobic digester effluent was obtained from a non-mixed pilot-scale reactor system operated at Walt Disney World, Orlando, FL, and fed an RDF MSW/sludge blend (64). The MSW feedstock was obtained from Baltimore, MD, and the municipal sewage sludge from the Walt Disney World Complex. Fresh effluent samples were sealed under anaerobic conditions and shipped overnight in ice for analysis. 

The spectrometer has also been applied successfully to the counting of environmental samples contaminated with worldwide fallout, reactor effluent, and debris from nuclear cratering experiments. In addition, it has been possible to carry out a variety of laboratory experiments not practical in the past because of the need for laborious radiochemical analysis such experiments have involved the analysis of several hundred samples each containing up to 20 isotopes. 

A standard arrangement for sampling gaseous products downstream of the reactor is shown in Fig. 5. In a needle valve (or a similar device), the reactor effluent is depressurized and the flow rate is controlled. In the vast majority of cases, the analytical instrument of the choice will be a gas chromatograph equipped with a capillary column, because such an instrument often allows a good separation of the products and, if equipped with an appropriate detector, a reliable quantitative analysis of these products. The working principle of gas chromatography, however, is inherently... 

Analytical Methods. Liquefied samples of the feed and reactor effluent were analyzed by gas chromatography. All gas chromatographs were tied to a chromatographic data processing system which determined peak areas and calculated sample compositions. Sample components were identified on the basis of their retention times. Response factors were determined experimentally, using synthetic blends resembling actual alkylation feeds and products. Except In those cases where RON was to be determined on a test engine, n-hexane was added to the samples as an Internal standard. 

Because the tapered element must vibrate freely, it is impossible to connect the sample cell outlet directly to a gas chromatograph (GC) or mass spectrometer (MS) for on-line analysis. Instead, a purge gas stream is passed along the outside of the tube to sweep the reactor effluent as it exits from the tapered element. 

All product analysis of effluent gas streams was performed by on-line gas chromatography. Two different gas chromatographs were employed, each with heated sample valve connected to the reactor effluent stream. Analysis of light (Ci-C5) hydrocarbons and dimethyl ether was performed by a Varian 1400 GC equipped with flame ionization detector. Separation of the products was accomplished by a 20 column (1/8" O.D.) packed with Porapak Q. Analysis of hydrocarbons in the C5 to... 

C 2 range was accomplished by use of a Supelco SPB-1 capillary column, which is 60 meters long with an inside diameter of 0.75 mm. In the course of sample analysis, the column temperature was held at 308 K for 12 minutes following sample injection, then increased at 4 K/minute to 398 K, where the temperature was held constant for 10 minutes. This heating pattern provided good separation characteristics, allowed products up to C 2 to elute before cooling, and permitted capillary column analysis of the reactor effluent streams every 60 minutes. 

Reactor effluent was continuously fed to a 0.25 ml sampling loop located inside a Hewlett-Packard Model 2520 Gas Analyzer. Separation of the products was over two serial columns, 6 x 1/8" Poropak Q 80/100 mesh, followed by 10 x 1/8" molecular sieve 5A 60/80 mesh. Thermal conductivity detection was used with helium carrier gas. Columns were isothermal at 60 C. 

The feed to the reactor contains ethylene, steam, and an inert gas. A sample of the reactor effluent gas is analyzed and found to contain 43.3 mole% ethylene, 2.5% ethanol, 0.14% ether, 9.3% inerts, and the balance water. 

Catalyst activities were measured at alkane conversions 6 - 80% for the gas mixture of reactants [90.6 vol.% of He + 8.4 vol.% of O2 + 0.96 vol.% of C2Hg] (-2.5-fold over-stoi-chiometric excess of oxygen the space velocity 2 10 h ). Samples of the reactor effluent were injected periodically into a chromatograph with a catarometer. Carbon dioxide and water were obtained as major products in all catalytic runs. Traces of ethene were also detected in some runs. 

The activity of the catalysts in N2O decomposition was tested in the same flow microreactor at 320 - 520°C and space velocity 2 10 h using the gas mixture [93 vol.% of He + 6.88 vol.% of N2O]. Samples of the reactor effluents were periodically analyzed by GC, with catarometer, using a Polisorb column. 

At each operating condition, triplicate samples of the reactor effluent were collected for analysis. Quantification of liquid products was accomplished by triplicate analysis of each of these samples using a Waters High Performance Liquid Chromatograph (Model... 

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