## 2 Materials and Methods  
### Materials and Laboratory Tests  
Heavy atmospheric gas oil (HAGO), light vacuum gas oil (LVGO), and heavy vacuum gas oil (HVGO) from a commercial H-Oil ebulated bed vacuum residue hydrocracker with property range of variation shown in our recent research [29] were subject to ASTM D 7169 and ASTM D 1160 distillation analysis. Besides, straight run vacuum distillate, stabilized hydrotreated vacuum distillate, and diesel fraction from a FCC feed hydrotreater were also subject to ASTM D 7169 [30] and ASTM D 1160 [31] distillation analysis. Density at 15 \({}^{\circ}\)C of the studied oils was measured in accordance to ASTM D 4052 method [32].  
The physical vacuum distillation analyses were carried out in Euro Dist MPS (ROFA) according to ASTM D-1160 requirements. The pressure in the Euro Dist MPS ASTM D-1160 apparatus during the whole analysis was 1 mm Hg.  
The HTSD analyses were carried out with the Agilent Technologies GC System 7890B, which was equipped with FID (flame ionization detector). Liquid nitrogen was used as a coolant. The carrier gas was helium with 99.9999% purity (14 mL/min), the inlet pressure was 1.2 psi (8.27 kPa) with the total flow equal to 87 mL/min. Hydrogen was used as a fuel gas (40 mL/min) and nitrogen was a makeup gas (15 mL/min), both with high purity (99.999%). The installed column was 5 m long, 530 \(\upmu\)m in diameter and the film thickness was 0.15 \(\upmu\)m. The oven operated under the program from \(-20\)\({}^{\circ}\)C to 430 \({}^{\circ}\)C at a ramp rate of 15 \({}^{\circ}\)C/min and a 4 min hold time at the maximum temperature. The injector was programmed to operate from 50 \({}^{\circ}\)C to 450 \({}^{\circ}\)C, at a rate of 15 \({}^{\circ}\)C/min, injected sample volume was 4 \(\upmu\)L. Before the simulated distillation analyses of the studied oil samples they were stirred preliminary, accurately weighted to achieve 2 weight percent of studied oils dissolved in carbon disulphide (0.03 g of the sample dissolved in 1.5 mL CS\({}_{2}\) (99.9%)). All prepared samples were stored at a temperature around 4 \({}^{\circ}\)C prior to analyses. The simulated distillation characteristics were automatically calculated by the SIMDIS software and the distillation curve boiling point in \({}^{\circ}\)C versus evaporate in wt.% was obtained. Minor intervention of the operator took place during the chromatograms processing. The HTSD GC was calibrated with a blend of normal paraffins having a carbon number between C\({}_{5}\) and C\({}_{120}\). The software (GC OpenLab CDS with Simdis program for ASTM D-7169) used in this application of HTSD allows estimating of the final boiling point of the residual oils higher than 750 \({}^{\circ}\)C.  
The repeatability of both studied laboratory distillation methods ASTM D 7169 and ASTM D 1160 applied to the H-Oil heavy distillates investigated in this work are summarized in Table 1. The data in Table 1 also include the costs of performance of a single analysis by both methods, expressed in USD.  
\begin{table}
\begin{tabular}{c c c} \hline
**Evaporate, \%** & **95\% CL (ASTM D 7169), \({}^{\circ}\)C** & **95\% CL (ASTM D 1160), \({}^{\circ}\)C** \\ \hline IBP & 9 & 17 \\
5 & 3.0 & 3.2 \\
10 & 3.0 & 3.2 \\
20 & 3.0 & 3.2 \\
30 & 4.0 & 3.2 \\
40 & 4.0 & 3.2 \\
50 & 4.0 & 3.2 \\
60 & 4.0 & 3.3 \\
70 & 4.0 & 3.3 \\
80 & 4.0 & 3.3 \\
90 & 4.0 & 3.3 \\ Cost per a single analysis, USD & 104 & 64 \\ \hline \end{tabular}
\end{table}
Table 1: Repeatability of the distillation methods ASTM D 7169, and ASTM D 1160 applied to the studied H-Oil heavy distillates.