Maya crude

Ylolds Typical examples North slope vac. resid Maya crude P.R. Springs bitumen... 

Ancheyta-Iuarez, J. Maity, S. K. Betancourt-Rivera, G., et al., Comparison of different Ni-Mo/alumina catalysts on hydrodemetallization of Maya crude oil. Applied Catalysis, A General, 2001. 216(1-2) pp. 195-208. 

Both hydrogen addition and carbon rejection processes will be necessary in any realistic scheme of heavy oil upgrading (Suchanek and Moore, 1986). Most coker products require hydrogenation and most hydrotreated products require some degree of fractionation. For example, to maximize yields of transport fuels from Maya crude, efficient carbon rejection followed by hydrogenation may be necessary. There are various other approaches to the processing of other heavy oil residua (Bakshi and Lutz, 1987 Johnson et al., 1985). As of now, it is not known which combination of processes best converts a heavy feedstock into salable products. 

Rudzinski, W.E., Oehlers, L., Zhang, Y., 2002. Tandem mass spectrometric characterization of commercial naphdienic acids and a Maya crude oil. Energy Fuels 16 (5), 1178— 1185. 

Alkanes form a significant proportion of crude petroleum samples (16% of Athabasca bitumen and 32% of Maya crude [89]) and would normally be heptane soluble and part of the maltene fraction. Alkanes are also found in coal tars formed by pyrolysis without extensive secondary thermal treatment [81]. LD-MS at 337 nm does not ionize alkanes [90], and therefore, ali-phatics will not appear in the mass spectra alkanes can be ionized by silver ion adduction and LD, but this method has not been applied in work discussed here. 

The Maya crude oil and asphaltene fractions have been studied [75,77,91]. A typical elemental analysis of the Maya crude is listed in Table 33.1, and the fraction weights are shown in Table 33.2. Figure 33.4A shows the mass spectra of the maltene fraction at different levels of LP spectra 1 and 2 barely exceed the ionization threshold, and spectra 4 and 5 show excessive LP with... 

Herod, A.A., Morgan, T.I, Alvarez, R, George, A., Millan, M., Kandiyoti, R. (2009) Analysis of Maya crude oil. Preprints ACS Fuel Div, National Meeting, Salt Lake City, March, 54(1), 28-29. 

Zhao, B., Shaw, J.M. (2007) Composition and size distribution of coherent nanostructures in Athabasca bitumen and Maya crude oil. Energy Fuels, 21, 2795-2804. 

Heck, R.H. Rankel, L.A. DiGuiseppi, F. T. Conversion of petroleum resid from Maya crude Effects of H-donors, hydrogen pressure and catalyst. Fuel Process. TechnoL, 1992, 30,69-81. 

Rudzinski WE, Aminabhavi TM, Sassman S, Watkins LM. Isolation and characterization of the saturate and aromatic fractions of a Maya crude oil. Energy FuelS, 2000,14 (4), 839-844. 

Trejo, F., Ancheyta J., (2007). Characterization of Asphaltene Fractions from Hydrotreated Maya Crude Oil. Ind. Eng. Chem. Res., 46, 7571-7579 F. Trejo F. Ancheyta J. Morgan T. J. , Herod A. A., Kandiyoti R., (2007). Characterization of Asphaltenes from Hydrotreated Products by SEC, LDMS, MALDI, NMR, and XRD. Energy Fuels 2007,21,2121-2128... 

Zhao, B. Shaw, J.S. (2007). Composition and Size Distribution of Coherent Nanostructures in Athabasca Bitumen and Maya Crude Oil. Energy Fuels. Vol.21, pp. 2795-2804 Zeng, H. Song, Y.Q. Johnson, D.L. Mullins, O.C. (2009). Critical Nanoaggregate Concentration of Asphaltenes by Low Frequency Conductivity. Energy Fuels, Vol.23, pp. 1201-1208... 

For residue treatment, an important economic factor is the lifetime of the catalyst. Even with a guard chamber to protect the main reactors, the catalyst can rarely process more than 5000 tons of feed per ton. Of course, the lifetime of the catalyst is directly related to the type of feed processed and inversely proportional to its metal content. For a feedstock containing more than 400 ppm of metals (Maya crude, for example), if a demetallization level of 60% is achieved, the deposit of metals on the catalyst will be 240kg (counted as metal) per ton of catalyst after an onstream time corresponding to lOOOm /ton. 

Diaz-Ramirez, I., Ramirez-Saad, H., Gutierrez-Rojas, M. Favela-Torres, E. 2003. Biodegradation of Maya crude oil fractions by bacterial strains and a deimed mixed culture isolated from Cyperus laxus rhizosphere soil in a contaminated site. Can J Microbiol, 49, 755-761. 

Rudzinski, W. E. Oehlers, L. Zhang, Y. (2002). Tandem Mass Spectrometric Characterization of Commercial Naphthenic Adds and a Maya Crude Oil. Energy Fuels, 16,1178-1185, ISSN 0887-0624. 

Sanchez, S., Ancheyta, J. 2007. Effect of pressure on the kinetics of moderate hydrocracking of Maya crude oil. Energy Fuels 21 653-661. 

Rana, M.S., Ancheyta, J., Rayo, P, Maity, S.K. 2004. Effect of alumina preparation on hydrodemetallization and hydrodesulfurization of Maya crude. Cafo/.rodlay98 151-160. 

Q Modeling of Bench-Scale Reactor for HDM and HDS of Maya Crude Oil... 

This chapter is devoted to illustrate the modeling and simulation of a heavy oil hydrotreating experimental bench-scale reactor. Hydrodesulfurization and hydrodemetallization of Maya crude oil was carried out at moderate reaction conditions. The parameters of the kinetic model were derived from experimental data at different reaction conditions of liquid hourly space velocity (LHSV) (0.33-1.5) and temperature (380°C-420°C) keeping constant the pressure and hydrogen-to-oil ratio (6.9 MPa and 5000 std fP/bbl oil, respectively). The bench-scale reactor is modeled as one-dimensional heterogeneous. The chapter gives details about the experiments, the development of the model, and its application to simulate the HDS and HDM of Maya crude oil. 

The feedstock used in our experiments was Maya crude oil whose main properties are reported in Table 9.1. Sulfur content in feedstock and products was determined with an HORIBA eqnipment (SLFA-2100), by using the standard ASTM D-4294 method. Boiling point curve was obtained by simnlated distillation by using the ASTM D-5307 method. 

The same Maya crude oil was used as feedstock. More details of Maya crude oil properties and its classification respect to other crudes according to the content of metals, sulfur, and API gravity were reported by Rana et al. (2007). The same NiMo/ AI2O3 commercial catalyst, loading and sulfiding procedures, as well as characterization techniques were also used. Other experimental details were reported previously (Ancheyta et al., 2001). Experiments were conducted at the following conditions pressure of 6.9, 8.3, and 9.8 MPa, temperature of 380°C-420°C, 5000 standard cubic feet per barrel of H2/oil ratio, and 1.5,0.5, and 0.33 h EHSV in the same isothermal bench-scale unit mentioned in the previous section. 

After the application of the procedure described in Figure 11.2 and recommendations given earlier, a set of model parameters of the continuous kinetic model for the case of study of Maya crude oil hydrocracking was obtained. The values were a = 0.245, flo = 1-396, = 22.0, 8 = 4.46 x lO , and = 0.537h->. 

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