Wet-test meter

During the development of this procedure, evolution of carbon dioxide was monitored with a wet-test meter. At the bath temperature given (160°), sodium chlorodifluoroacetate... 

The reaction starts spontaneously and is mildly exothermic. Moderating the temperature by use of a water bath diminishes the amount of bromine and product carried off by the carbon dioxide evolved. The reaction can be followed by use of a tetra-chloroethane bubbler, and at the end of the reaction the solvent in the bubbler can be used to wash the mercuric bromide. The checkers followed the reaction with a wet test meter presaturated with carbon dioxide 52-60% of the theoretical amount of carbon dioxide was evolved. 

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. 

The rate of decarboxylation can be followed qualitatively by collecting the liberated carbon dioxide over water, e.g., by the use of a wet test meter. 

SO2 content of the gas was determined by sparging into a 125 ml gas washing bottle containing a known amount of I2 in acetate buffer at pH A-5.5 with a starch indicator. N2 flow was measured by a wet test meter. 

Wet test meter, bubble tube, rotameter, and manometer Assorted spare parts pumps, fuses, orifices, etc. 

We are currently checking orifices prior to each survey with the direct reading rotameter, and washing them in isopropyl alcohol afterwards. Every six months, the calibration checks are performed with the wet test meter. As long as field checks and rotameter calibration checks agree with the bi-annual wet test meter calibration results, we feel the orifices are performing accurately. 

It is necessary, however, to correct for volume if the calibration tool is not a true primary calibration source. Our wet test meter is supposed to be accurate within 4 0.5%, and the volume has been calibrated by personnel at the University of N.C. at Chapel Hill against their primary standard. There are also small differences in flow rates if there are large temperature changes between the calibration site and the sampling site (3). 

Methanol or dimethyl ether feeds were fed from an ISCO positive-displacement pump. Liquid products were collected in a room-temperature trap and gaseous products were analyzed by on-line gas chromatography and volumes measured by a wet-test meter. The catalyst could be regenerated in-situ by switching to a nitrogen/air mixture. 

Different methods used for calibrating samplers include rotometers, wet-test meters, pressure gauges across fixed orifices, mass flow meters, hot wire flow meters and bubble tubes. Each of these calibration devices requires an appropriate correction factor. Some of the devices measure mass flow rather than volumetric flow. Sampling requires volumetric flow calibration. 

The flash gas from the top of F-l passed through a wet-test meter to a sample tap and was vented to the atmosphere. Condensed liquid product was collected through a valve at the bottom of F-7, weighed, and analyzed. 

A three-zone furnace (top to bottom are 31, 6", and 3", respectively) was used to maintain isothermal conditions along the reaction zone. Pressure was controlled by a back pressure regulator on the exit stream. A post reactor dropout trap was installed to condense the steam and hydrocarbon condensates. Downstream dry product flow rates were measured by a wet test meter. 

The effluent stream from the reactors flowed through a condenser and cylinder where liquid products were separated and collected. The exit gas pressure was reduced to 1 atm, and products were sampled on-line to measure the concentrations of CO, CO2, N2, and CH4, Finally, the effluent was discharged to the outside atmosphere via a wet test meter. The compositions of liquid products were measured by gas chromatography. The activity is reported in terms of the methanol yield. 

Packed tower studies were made with a borosilicate glass column 4 inches in inside diameter packed with /4-inch ceramic Intalox saddles. The feed was metered through a rotameter from a constant-head tank, and distributed through the tower with a perforated aluminum plate. Aluminum tubing and polyethylene pipe were used to connect the ozone generator to the tower. A continuous sample was withdrawn from the tower bottom for analysis, and exit gas from the top of the tower was conducted to a wet-test meter for volume measurements. Ozone was absorbed in 5% potassium iodide solutions and titrated with thiosulfate to a starch end point. 

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