Autoclave model

The hydrogenation reactor consisted of a 1-L Hastelloy C autoclave (Model 464IM, Parr instmment company, Moline Illinois) equipped with a belt-driven, magnetic stirrer (1000 rpm). 

All reactions were run in a Parr stirred autoclave (Model 4561) at 1000 psi H2 and 200°C for 6h. A weighed quantity (0.5 g dry basis) of the catalyst, Ru/C or Ni/Re/C, was introduced into the reactor and reduced at 250 C and 200 psi H2 (Ru/C) or at 280°C and 500 psi H2 (Ni/Re/C) for 13 hours. After cooling, 100ml of solution (l.OM GO and O.l-l.OM KOH) was added to the closed reactor. For reactions in solvent mixtures, entries 1-4 in Table 2, the water/solvent ratio was 1/9 (v/v). When the solvent was either t-BuOH or 1,4-dioxane, 1.5 g of water was added to the solution to facilitate dissolution of KOH, because of its low solubility these solvents. Once steady state was achieved following heatup, samples were taken at 30 minute intervals for the first hour, and then hourly, and analyzed via HPLC. The HPLC column was a BIORAD Aminex HPX-87H run at 65 C with 5mM H2SO4 as the mobile phase at a flow rate of 0.6mFmin, using both UV (210 nm) and refractive index (RI) detection. 

Perhaps a more severe comparison of model response is the time history of the centerline temperature. These values reflect the interaction of several phenomena the reaction itself, the heat liberated by the reaction, the heat storage capacity of the material, and the rate at which heat can be carried away from the centerline region by conduction. Figure 8 shows the temperatures predicted by the Chiao and finite element models, as well as the imposed autoclave temperature history. It also includes five thermocouple readings which were reported in Chiao s manuscript (8). 

In this paper the effects of kinds of coal, pasting oil, catalyst and reaction temperature on coal liquefaction are illustrated, and a few kinetic models for catalytic liquefaction of five coals carried out in an autoclave reactor are proposed. 

The heat of decomposition (238.4 kJ/mol, 3.92 kJ/g) has been calculated to give an adiabatic product temperature of 2150°C accompanied by a 24-fold pressure increase in a closed vessel [9], Dining research into the Friedel-Crafts acylation reaction of aromatic compounds (components unspecified) in nitrobenzene as solvent, it was decided to use nitromethane in place of nitrobenzene because of the lower toxicity of the former. However, because of the lower boiling point of nitromethane (101°C, against 210°C for nitrobenzene), the reactions were run in an autoclave so that the same maximum reaction temperature of 155°C could be used, but at a maximum pressure of 10 bar. The reaction mixture was heated to 150°C and maintained there for 10 minutes, when a rapidly accelerating increase in temperature was noticed, and at 160°C the lid of the autoclave was blown off as decomposition accelerated to explosion [10], Impurities present in the commercial solvent are listed, and a recommended purification procedure is described [11]. The thermal decomposition of nitromethane under supercritical conditions has been studied [12], The effects of very high pressure and of temperature on the physical properties, chemical reactivity and thermal decomposition of nitromethane have been studied, and a mechanism for the bimolecular decomposition (to ammonium formate and water) identified [13], Solid nitromethane apparently has different susceptibility to detonation according to the orientation of the crystal, a theoretical model is advanced [14], Nitromethane actually finds employment as an explosive [15],... 

Shortly after interruption of vacuum distillation from an oil-bath at 115°C to change a thermometer, the ester exploded violently and this was attributed to overheating [1], A commercial sample of undetermined age exploded violently just after vacuum distillation had begun [2], In an examination of thermal explosion behaviour, the title compound was used as a model compound in autoclave... 

For thermal protection during reentry from space, Dornier manufactured some model shingles from SiC/SiC and C/SiC. Fig. 13 shows two shingles each reinforced with two beads. For these parts a special prepreg was developed which had a 2.5 D fiber structure and enabled easy forming by autoclave tools to be carried out. 

Rubisov, D. H. Papangelakis, V. G. Sulphuric acid pressure leaching of laterites—a comprehensive model of a continuous autoclave. Hydrometallurgy 2000, 58, 89-101. 

Catalytic experiments. The runs are performed in a 300mL static reactor (Autoclave Engineers Model AE 300) for 15hrs under an initial 20 bar pressure with a sample weight leading to 0.U mg-atom of metal. Neither the unloaded zeolites nor the molecular clusters are active in CO hydrogenation under our experimental conditions. 

The hydrothermal carbons obtained in the end from soluble, non-structural carbohydrates are micrometer sized, spherically shaped particle dispersions, containing a sp2 hybridized backbone (also responsible for the brown to black color) decorated with a dense layer of polar oxygenated functionalities still remaining from the original carbohydrate. The presence of these surface groups offers the possibility of further functionalization and makes the materials more hydrophilic and well-dispersible in water. The size of the final particles depends mainly on the carbonization time and precursor concentration inside the autoclave, as well as additives and stabilizers potentially added to the primary reaction recipe. An SEM image of a model reaction illustrating this dispersion state is shown in Fig. 7.1. 

Chemical Data Systems, Div. of Autoclave Engineering, 7000 Limestone Rd., Oxford, PA 19363. Sample Concentrators, Models 320, 330 CDS Geochemical Research System, Model 820 Model 8000 Series Micro-Pilot Plant Systems. 

All the hydrocracking/hydrogenation experiments were carried out in 500 ml capacity spinning type autoclaves. Two autoclaves of this design were used and the autoclaves were compared in experiments using the model compound phenanthrene, chosen because phenanthrene and its hydro-derivatives represent a large proportion of the solvent which is recycled in coal liquefaction processes. 

Hydrogenation of model aromatic compounds All the hydrogenation experiments were carried out in 500 cm capacity spinning/falling basket autoclaves manufactured by Baskerville Scientific Ltd. Detail of the autoclaves is provided elsewhere in this book (Harrison, Doughty and Ali). Apart from further experiments with phenanthrene, all the... 

Typical reaction procedure is as follows biphenyl (25 mmol), propene (50 mmol), HM (1 g), and trans-decalln (20 cm ) were heated in an autoclave at 200°-300°C for 4 h. Products were analyzed by a Hewlett-Packard Gas-chromatograph Model 5890 equipped with a 25 m capillary column of Ultra-1. 

A smart closed-loop system is composed of a heating/pressure device, such as a press or autoclave, sensors able to gather data in situ from the composite part, and smart software that collects the sensor information, interprets it, and then makes decisions that control the fabrication device. The smart software combines both the predictions of the processing model and the insight of operator experience. Figure 4.20 is a schematic diagram of the FDEMS... 

The stability, growth, and transport of voids during composite processing is reviewed. As a framework for this model, the autoclave process was selected, but the concepts and equations may be applied equally effectively in a variety of processes, including resin transfer molding, compression molding, and filament winding. In addition, the problem of resin transport and its intimate connection with void suppression are analyzed. 

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