Autoclave, slurried hydrogenation

The slurry is introduced into a 3-liter rocking autoclave, and hydrogen admitted to a pressure of 1,500 psi. The autoclave is heated to a temperature of 150°C in one hour and held at this temperature for 2% hours more. Pressure rises to about 1,800 psi and then declines to about 1,600 during the hydrogenation. The autoclave is then cooled, emptied, and the catalyst filtered from the product. The filtrate is then concentrated under vacuum on a hot water bath to remove a part of the water. 

The most common heterogeneous catalytic reaction is hydrogenation. Most laboratory hydrogenations are done on liquid or solid substrates and usually in solution with a slurried catalyst. Therefore the most common batch reactor is a stirred vessel, usually a stirred autoclave (see Figure 2.1.1 for a typical example). In this system a gaseous compound, like hydrogen, must react at elevated pressure to accelerate the process. 

Semi-batch hydrogenation involves feeding the nitrile to an autoclave, containing a slurry of catalyst in the reaction product, for a specified time period after which time the nitrile feed is stopped. After the nitrile feed is stopped, the reaction will continue for a short period of time while the residual unreacted nitrile is consumed. Close monitoring of the hydrogen uptake during the time period after the nitrile feed is stopped provides insight into the rate at which... 

In continuation of a previous work (1), catalytic hydrogenation of cinnamaldehyde has been studied in slurry phase using a high-pressure autoclave. A series of carbon powder (CP)-supported Pt catalysts with widely varying Pt dispersion and Pt location on the support has been used in the study. The purpose has been to find out how the location of the metal on the support and its dispersion affect the two parallel reaction paths, namely the hydrogenation of the C=0 and C=C bonds. 

FT synthesis was carried out in a 0.3 L autoclave-type slurry continuous stirred tank reactor under pressurized conditions. The catalyst was reduced with hydrogen... 

Kinetic experiments were carried out isothermally in autoclave reactors of sizes 500 ml and 600 ml. The stirring rate was typically 1500 rpm. In most cases, the reactors operated as slurry reactors with small catalyst particles (45-90 micrometer), but comparative experiments were carried out with a static basket using large trilobic catalyst pellets (citral hydrogenation). Samples were withdrawn for analysis (GC for citral hydrogenation and HPLC for lactose hydrogenation). The experimental details as well as qualitative kinetics are reported in previous papers of our group Kuusisto et al. (17), Aumo et al. (5). 

Coal Liquid Preparations. The coal liquids were produced in two stages as previously described in detail (1). In the first stage, crude coal liquids were produced by hydrogenation of a coal/tetralin slurry in a batch autoclave with 60-100 mesh Cyana-mid Aero HDS-3A catalyst (3.2 wt-pct NiO and 15.1 wt-pct MoO on an alumina support) at about 2,500 psig total pressure over a temperature program which increased slowly to a maximum of 400° C. 

The coal liquid is obtained by reacting Kentucky 9/14 coal-LRO slurry for 60 minutes at 410°C in an autoclave reactor under 2000 psig (13.9 MPa) hydrogen pressure. The product from the autoclave is collected and filtered using Watman 51 filter paper to remove the mineral matter and undissolved coal. The liquid product is saved and used for further hydrotreating studies. The analysis of the filtered product from the coal dissolution step is given in Table I. 

The coals (<250 ym) were hydrogenated in a 70 ml rocking autoclave using a 1 1 slurry of tetralin coal at initial hydrogen pressures of 1-10 MPa for 1 hour at a reaction temperature of 285°C. In related studies temperatures in the range 345-460 C were used at 6 MPa pressure. Both iron and tin-based catalyst systems were examined. 

Samples of each of the coal derived materials were reacted separately in the presence of several catalysts in a 70 ml batch autoclave using a 1 1 slurry of tetralinrmaterial at 425 C with an initial hydrogen pressure of 6 MPa for 1 hour at reaction temperature. The products from these reactions were separated into oils, asphaltenes, preasphaltene and THF insolubles. 

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