Reactor ceramic reactors

GP 7] [R 8] In a later study, a yield of about 40% is found for the same steel reactor [55]. For a ceramic reactor, an even higher yield of 45% is reported. This is explained by a reduction in blank activity (Figure 3.40) (see the sections Activity of... 

GP 11[ [R 19[ Temperatures close to 1200 °C, near the mechanical limit of the ceramic reactor material, have been achieved [9, 115], With improved sealing and better material, processing could lead to 1300 °C [9],... 

Reactor type Ceramic reactor with interdigitated electrodes Number of electrodes 20 anodes + 20 cathodes... 

Steele, B. C. H. (1987) in Ceramic Electrochemical Reactors, Ceramic, London. 

The growth of such structures is possible only from a gas phase and probably occurs as a result of dehydropolymerisation (polycondensation) [4,11 ]. Under more harsh reaction conditions multi-walled nanotubes grow as a loop on ceramic reactor walls (Fig. 3.4). We suggest that the benzene molecule could be the main fragment in the graphene network formation. At temperatures >600°C benzene rapidly undergoes dehydrogenation followed by diphenyl formation that can be considered... 

Figure 2.29 Photograph of the ceramic reactor housing and the quartz-glass tubulare microreactor (visible through the center hole) [59].

It is the opinion of the author that future research on reactor modeling should focus on developing models for reactors and processes which are as yet poorly understood. Examples of such systems include fluidized-bed reactors, membrane reactors, reactors used for the synthesis of ceramics, and low-pressure reactors used for the deposition and etching of thin films. 

Alkali, in the form of Na and K-containing species, can lead to a dramatic reduction in the durability of metal (alloy) and ceramic reactor components through a complex process known as hot corrosion (5). Examples of energy systems where this process occurs include, coal-fired utility boilers, turbines, gasifiers,... 

Research on separation of hydrogen isotopes is focused on the aspects related to safe operation of nuclear reactors and separation of tritium. Apart from separators based on palladium alloys [142-145], one can find catalytic units with different metallic membranes and various types of integrated systems with catalytic ceramic reactors [146-154]. 

D. Lafarga, J. Santamaria and M. Menendez, Methane oxidative coupling using porous ceramic membrane reactors. I. Reactor development. Chem. Eng. Sci., 49 (1994) 2005. 

An isothermal reactor concept incorporating a ceramic membrane is more attractive compared to an adiabatic reactor concept from a thermodynamic point of view. In this concept we assumed a reactor with reactor tubes located in a direct-fired heater and operated in a cyclic way to remove coke formed on the catalyst. Parallel bed and heaters have been assumed [35-37]. 

The Pt/ZrO2 and Ce-promoted catalysts were prepared as described by Stagg and Resasco. All catalysts were reduced at 500°C for one hour before the reaction. The dry reforming reaction was performed in a fixed bed reactor. The reactor was a 0.3-m long ceramic reactor tube (6.35-mm o.d., 4.0-mm i.d.), sealed inside a stainless steel tube at higher pressures and contained a quartz thermocouple well. The reactor was loaded with 0.012 grams of catalyst mixed with 0.030 grams silica and held in place by quartz wool. The reactions were carried out at 800°C, and at 1 and 14 bar. Reaction products were monitored by a quadrupole mass spectrometer. 

Figure4-13 Membrane reactors. (PhotoCourtesy of CoorsCeramics,Golden. Colorado.) (a) Photo of ceramic reactors, (b) cross section of IMRCF. (c) cross section of CRM. (d) schematic of IMRCF for mole balance.

COX, B.G., PRUDEN, B.B., JEJE, A.A., Ceramic Reactor/Exchanger for H2S Dissociation, (Proc. 7th Canadian Hydrogen Workshop, 1995, Quebec City), MEHTA, S.K., BOSE, T.K. (Ed.), Canadian Hydrogen Association (1995) 329-352. 

This work had been supported by NEDO, as part of the Advanced Ceramic Reactor Project. 

The activity tests have been performed in a ceramic reactor located in a tubular furnace. The catalyst is mounted in the reactor and the temperature is raised from 250 C up to 500 C and 1000 C, respectively (depending on the calcination temperature), at the rate of 3 C/min. The total gas flow was 5.7 dm /min, giving a gas hourly space velocity of 100 000 h". The fuel concentration was 1.0 vol% of CH4 in air for all experiments. For the tests in presence of sulfur species, 25 ppm SO2 was added in the gas stream. The exhausts were analyzed by online gas chromatography (GC Varian 3800) equipped with a thermal conductivity detector. The various sulfur species that could be present in the gas stream were removed prior to entering the analytical system. 

Quan, X. Shi, H. Zhang. Y. Wang,). Qian, Y., Biodegradation of 2,4-dichlorophenol in an air-lift honeycomb-like ceramic reactor. Process Biochem. 2003, 38, 1545-1551. 

The nuclear design calculations for this 1000-MWe fast ceramic reactor used a conservative set of nuclear data. There is experimental evidence to suggest that calculations using these data predict (1) a neutron spectrum that is too hard (quantitative information is given in the paper by Greebler et al. (8) and (2) a positive Doppler contribution from Pu which is too large. 

P. Greebler et al., Calculated Nuclear Reactor Parameters and Their Uncertainties in a 1000 MWe Fast Ceramic Reactor. GEAP-4471 (1966). 

B. A. Hutchins, The effects of resonance overlap on the Doppler coefficient in a fast ceramic reactor. GEAP-4630 (1964). 

---