Patent ID: 7642095
Filing Date: 2010-01-05
Classification: C10G,G01N

Abstract:
1. A process for predicting the Mini Rotary Viscometer (MRV) properties of formulated oils which comprises: (a) injecting a basestock sample into a first column of a 2-dimensional gas chromatograph, said first column being coated with a non-polar material to separate the basestock sample into a series of first dimension sample components having a first set of retention times; (b) injecting the separated first dimension sample components from step (a) into a second column coated with a semi-polar material to further separate the separated first dimension sample components into second dimension sample components having a second set of retention times; (c) subjecting the first and second sets of retention times to qualitative analysis to identify n-paraffin and iso-paraffin components or groupings thereof and to quantitative analysis to identify the quantity of the n-paraffin components and iso-paraffin components or groupings thereof having carbon numbers in the lubricant basestock range; (d) grouping the iso-paraffin components into x groupings where x is a number from 0 to 3 for each identified individual lube paraffin in the carbon number range from 16 to 50; (e) selecting a lower carbon number n and an upper carbon number m; (f) identifying the n-paraffin and a first, second and third iso-paraffin group A, B and C for each individual carbon number over the range from n to m; (g) calculating a Paraffin Index over a given carbon range bounded by a lower carbon number, n, and an upper carbon number m, wherein the Paraffin Index is calculated by: where L is the carbon number of the identified paraffins over the carbon range from n to m in the baseoil sample, (n-paraffin)L is the amount of the normal paraffin at each individual carbon number, (Iso-paraffins group A)L is the amount of iso-paraffins in a first group A at each individual carbon number, and (Total paraffins)L is the sum of n-paraffin plus iso-paraffin groups A, B and C at each individual carbon number; (h) repeating steps (a)-(g) for a series of basestock samples; (i) measuring the MRV for a series of formulated basestock samples; (j) plotting measured MRV of the formulated basestock samples versus Paraffin Index of basestock samples to produce a plot having a slope (M) and a y-intercept (B); and (k) calculating the predicted MRV using the equation: Predicted MRV=(M)* (Paraffin Index)+(B).