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Transform ASTM D 86 distillation cuts to ASTM 2892 (TBP) light cuts The results of ASTM D 86 distillations can be converted into an atmospheric ASTM 2892 TBP by using an equation equivalent proposed by Riazi and published by the API Equation 3: T* = aTb

With: T* = Temperature of TBP test [ºK] T = Temperature distillation D 86 [ºK] a, b = Constants depending on the fraction distilled.

Application Example:

The accuracy of method depends on the smoothness of curve. Errors affect the points in the low % distilled ranges. Average error is in order of 5 °C for smooth curve. Wauquier pp 98-104. Transformation of atmospheric TBP curve to ASTM D 86 API recommends a relationship established by Riazi (1982)

T* = aTb

With: T = Temperature TBP [K] T* = Temperature of ASTM D 86 [K] a, b = Transformation Coefficients (See application example) Application Example:

Source: Petroleum Refining Volume 1: “Crude oil Petroleum Products” by Jean Pierre Wauquier. Institut Francais du Pétrole. Editions Technip. pp 98 & ss.

Distillation ASTM D86 to TBP (Riazi Method)Volume % distilled Coefficient a Coefficient b Temperature

D86 ºCTemperature

TBP ºC0 0,9177 1,0019 58,9 35,0

10 0,5564 1,0900 75,1 55,030 0,7617 1,0425 102,5 95,050 0,9013 1,0176 134,3 135,070 0,8821 1,0226 169,5 175,090 0,9552 1,0110 204,4 215,095 0,8177 1,0355 215,9 225,0

Distillation TBP to ASTM D86. Table 4.16a WauquierVolume % distilled Coefficient a Coefficient b Temperature

TBP ºCTemperature

D86 ºC0 1,08947 0,99810 14,1 36,5

10 1,71243 0,91743 33,4 54,130 1,29838 0,95923 68,9 76,950 1,10755 0,98270 101,6 101,570 1,13047 0,97790 135,1 131,090 1,04643 0,98912 180,5 171,095 1,21455 0,96572 194,1 186,5