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The combined effects of H2S, H20, and NH3 on liquid-phase hydrodenitrogenation (HDN) of quinoline in a batch slurry reactor were studied using presulfided commerical Ni-Mo/7-Al203 catalyst, at 7.0 MPa and 330, 350, and 375 °C. The overall and individual rate constants were determined, and the product distributions, obtained through kinetic modeling, were compared with the experimental data. The kinetics of the overall HDN of quinoline were found to be 0.8 order with respect to total nitrogen concentration, whereas individual rates were first order. Both qualitative and quantitative effects of H2S, H20, and NH3 on the HDN of quinoline were presented. The presence of H2S alone enhanced the overall HDN rate significantly. H20, as such, enhanced the overall HDN to some extent; however, the effect of H2S was dominant when H2S and H20 were together. NH3 alone did not show any effect. No effect on the HDN of quinoline was found in the presence of H2S and NH3 together. The combined effects of H2S, H20, and NH3 have resulted in a decrease in hydrogenation steps, but an enhancement in hydrogenolysis steps. The net effect was an increase in the overall HDN rate.Heavy oils such as petroleum crudes and synthetic crudes derived from coal, shales, and tar sands are characterized by having substantial amounts of sulfur, nitrogen, oxygen, and organometallic compounds in addition to the polynuclear aromatics and asphaltenes. Sulfur and ni-

Abstract:In studies on chemical kinetics, generally after the rate data have been taken, a mechanism and an associated rate law model are proposed based on the data taken. Frequently, more than one mechanism and rate law may be consistent with data. In order to find the correct rate law, regression techniques (model discrimination) are applied to indentify which model equation best fits the data by choosing the one with the smaller sum of squares. With this non-linear regression technique, rate parameters with 95% confidence limits are calculated along with residues. Of course, model parameters must be realistic. For example, reaction rate constants, activation energies or adsorption equilibrium constants must be positive by comparing the calculated value of parameters with 95% confidence limits, one can judge about the validity of the model.In this paper, model discrimination will be applied to certain data from the literature along with the suggested heterogeneous catalytic models such as Langmuir-Hinshelwood Kinetic Model or Rideal-Eley Model.A reaction of A + B C + D type have been selected (like methanation) with the rate laws given below:

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