Investigating the Kinetics of Biodesulfurization of Diesel

The technology of biodesulfurization requires that reactors, where the reaction can take place, must be designed. In order to do this, the kinetics of the process must be thoroughly understood. This work aims to investigate the kinetics of biodesulfurization of diesel. This was done by simulating the kinetics of the process alone and then with and without the effect of mass transfer. The kinetic parameters, maximum rate constant, νmax, and the Michaelis-Menton constant, KM, were estimated using the linear equations of Hanes, Lineweaver-Buck and Eadie-Hofstee. The values obtained for each of the parameters from the linear equations were close but are not the same. This necessitated the need to carry out a non-linear regression analysis on the substrate concentrationtime data. The analysis was done using Marquardt’s algorithm of non-linear regression analysis. The obtained results were then compared with experimental data, they both showed good correlation with the experimental data although the mass transfer influenced kinetics showed a better agreement with the experimental data. Based on the aforementioned findings, one may conclude that mass transfer played an important role in the kinetics of biodesulfurization of diesel

Pre-Treatment of Heavy Crude Oils for Refining

The economic unattractiveness of heavy crude oils in the global oil market scene is fast changing due to the looming scarcity of light oils. There are huge reserves of heavy oils to which refiners are being reluctantly attracted. The fully developed conventionally available refineries are, however, incapable of processing these heavy crudes without some major modifications of both process and equipment, which will be capital intensive. This thrust promises to be very viable and yield great benefits since heavy oil is relatively cheap. Process and equipment modification begins with the required pre-treatments of these heavy crudes to facilitate efficient and cost-effective refining. Low API gravity, high amounts of impurities, and high viscosity are the major challenges addressed in the pre-treatment section. An option for a unit for the removal of some impurities for some special heavy oils is proposed. This should be followed by a multi-stage desalting unit that may be replaced with a centrifuge and a preliminary hydrotreating unit

KINETIC ANALYSIS OF AROMATIZATION OF N-HEXANEON PLATINUM/ALUMINA CATALYST USING THE TIKHONOV REGULARIZATION TECHNIQUE

Tikhonov regularization, which is a new technique for converting time-concentration data into concentration-reaction rate data, was applied to the kinetic analysis of n-hexane aromatization on Platinum/Alumina Catalyst.The technique was used for the conversion of the experimental concentration-time data to rate-concentration data. Due to the ill-posed nature of the problem of obtaining of reaction rates from experimental data, conventional methods will lead to noise amplification of the experimental data. Hence, Tikhonov regularization technique is preferably employed because it is entirely independent of reaction rate models and it also manages to minimize noise amplification, thus, leading to more reliable results. The kinetic parameters obtained by the application of the Nelder-Mead simplex optimization technique to formulated mechanistic models was used to discriminate among rival kinetic models based upon physicochemical criteria and thermodynamic tests to give the rate of conversion of adsorbed hexene-1 to adsorbed methylcyclopentane when hydrogen is adsorbed as a bi-molecular specie as the rate determining ste

A Review of an Expert System Design for Crude Oil Distillation Column Using the Neural Networks Model and Process Optimization and Control Using Genetic Algorithm Framework

This paper presents a comprehensive review of various traditional systems of crude oil distillation column design, mod- eling, simulation, optimization and control methods. Artificial neural network (ANN), fuzzy logic (FL) and genetic al- gorithm (GA) framework were chosen as the best methodologies for design, optimization and control of crude oil dis- tillation column. It was discovered that many past researchers used rigorous simulations which led to convergence problems that were time consuming. The use of dynamic mathematical models was also challenging as these models were also time dependent. The proposed methodologies use back-propagation algorithm to replace the convergence problem using error minimal metho

KINETIC ANALYSIS OF AROMATIZATION OF N-HEXANEON PLATINUM/ALUMINA CATALYST USING THE TIKHONOV REGULARIZATION TECHNIQUE

Tikhonov regularization, which is a new technique for converting time-concentration data into concentrationreaction rate data, was applied to the kinetic analysis of n-hexane aromatization on Platinum/Alumina Catalyst.The technique was used for the conversion of the experimental concentration-time data to rate-concentration data. Due to the ill-posed nature of the problem of obtaining of reaction rates from experimental data, conventional methods will lead to noise amplification of the experimental data. Hence, Tikhonov regularization technique is preferably employed because it is entirely independent of reaction rate models and it also manages to minimize noise amplification, thus, leading to more reliable results. The kinetic parameters obtained by the application of the Nelder-Mead simplex optimization technique to formulated mechanistic models was used to discriminate among rival kinetic models based upon physicochemical criteria and thermodynamic tests to give the rate of conversion of adsorbed hexene-1 to adsorbed methylcyclopentane when hydrogen is adsorbed as a bi-molecular specie as the rate determining step

Application of Monte-Carlo Simulation to Estimate the Kinetic Parameters of n-Eicosane Pyrolysis and n-Heptane Catalytic Reforming

Pyrolysis of hydrocarbons and catalytic reforming of naphtha are important processes in petroleum refineries and petrochemical industries as they lead to production of light olefins, high octane gasoline, aromatics and so on. Thus, it is important to investigate their chemical kinetics in order to establish rate expressions or models for their reactions. In this research work, Monte-Carlo Simulation was applied to estimate kinetic parameters of two complex reactions: pyrolysis of n-Eicosane and catalytic reforming of n-Heptane. The rate models which were derived experimentally from previous work of Susu [18] were used directly as forward reaction models in the Monte-Carlo simulation model algorithm. This required the use of concentration-reaction rate data obtained from the experimental time-concentration data through a technique called Tikhonov regularization. The result revealed the values of rate constants ranging from 0.0138 – 48.301 hr-1 at different temperatures of 425, 440 and 450oC with minimum objective function of 0.01730 for the 1st order kinetic of n-Eicosane pyrolysis. For the 2nd order kinetic of n-Eicosane pyrolysis, the values of rate constants ranged from 10.8348 – 261.691 cm3.gmol-1.hr-1 at different temperatures of 425, 440 and 450oC with minimum objective function of 0.0678. The n-Heptane catalytic reforming was examined at 460oC with rate constants ranging between 1.270 and 86.8126. The methodology used predicted accurately well as there was good agreement between the calculated values and the examined experimental value