Hydrogenated Diesel Color

The kinetics of hydro-decolorization reaction of gas oils has been investigated in a pilot trickle-bed reactor.A kinetic model of gas oil hydro-decolorization has been established based on the study of the effects of process parameters on color of hydrotreated products: namely, the reaction temperature, hydrogen pressure, hydrogen/oil ratio and space velocity. In the model, the Arrhenius Equation is used to correlate the effect of temperature with the rate constant, and the effects of pressure and hydrogen/oil ratio on rate constant is expressed in terms of exponent power functions. For the work mentioned above, the activation energy has been calculated according to the established kinetic model, which is related to the properties of the feedstock.The color stability of hydrotreated diesel fuel is connected with the contents of unsaturated compounds and heteroatom compounds. A combination of two pseudo first-order autoxidation reactions that have different rate constants has been adopted to describe the color development of hydrotreated product during its storage. The two reactions refer to the conversions of color precursors: unsaturated compounds and heteroatom compounds. A function of color development is established according to the different color of the product at different storage time. From the above-mentioned, the color stability and final colorimetric rating of the hydrotreated product will be obtained from its properties.