Laser microraman study of reduced synthesized spinel powders

The Raman effect is the excitation or de-excitation of vibrational modes resulting from the inelastic scattering of light from a gas, liquid, or solid with a shift in energy from that of the usually incident radiation. Raman microscopy was performed on synthesized spinel powders of solid solution FexCr3-xO4 to determine the dependence of the vibrational modes upon the metal cations. The powders were synthesized in a combustion reaction using metal nitrates and urea. The oxide powders were reduced in a hydrogen/argon gas flow at high temperature

Chemistry and resources of heavy oil and natural bitumen deposits

Supplies of conventional crude oil are diminishing; therefore, it is important to understand the reservoir characteristics of unconventional oil deposits. Reservoirs of unconventional deposits contain oils heavier than 20° gravity API and natural bitumens (tar sands and oil sands) are more viscous than 10,000 cp. The resources of these hydrocarbons are very large in the heavy oil of the Orinoco Oil Belt of Venezuela as well as in the natural bitumen of the Western Canada Sedimentary Basin of Alberta, Canada. In addition many small deposits of heavy oil and bitumen occur in the United States. Although the total resources of unconventional oil deposits are impressive, many environmental, economic, and technological factors affect their producibility. A thorough knowledge of the characteristics of reservoir rock includes the mineralogy of the host rock, the amount and type of clay minerals present, and the physical and chemical composition of the hydrocarbons. The presence of trace elements is also important to the utilization of these unconventional oil deposits. The attributes of each individual deposit must be studied and defined before recovery techniques can be modelled and before subsequent steps for upgrading refineries and transportation are taken

Annotated record of the detailed examination of Mn deposits from U.S.N.S. Kane 1968 expedition in the Northern Atlantic ocean

Five of 34 dredge hauls taken in the Atlantic Ocean recovered a material tentatively described on shipboard as a salmon-colored clay. X-ray diffraction analysis showed the clay material to consist principally of palygorskite. Occurring with the palygorskite are quartz, calcite, and dolomite. It is suggested that the palygorskite (and sepiolite) is the result of chemical precipitation brought about by the reaction of hydrothermal solutions with sea water

Experimental Study on the Impact of Thermal Maturity on Shale Microstructures Using Hydrous Pyrolysis

Hydrous pyrolysis was applied to four low-maturity aliquots from the Utica, Excello, Monterey, and Niobrara Shale Formations in North America to create artificial maturation sequences, which could be used to study the impact of maturation on geochemical and microstructural properties. Modified Rock-Eval pyrolysis, reflectance, organic petrology, and Fourier transform infrared spectroscopy (FTIR) were employed to analyze their geochemical properties, while gas adsorption (CO2 and N2) was used to characterize their pore structures (pores < 200 nm). Organic petrography using white and blue light (fluorescence) before and after hydrous pyrolysis showed that amorphous organic matter cracked into solid bitumen, oil, and gas during hydrous pyrolysis. A reduction of the CH2/CH3 ratio in hydrous pyrolysis residues was observed from FTIR analysis. Rock-Eval pyrolysis showed that kerogens in the four samples were dissimilar, and hydrous pyrolysis residues showed smaller hydrogen index and Sh2 values than starting materials. Results from CO2 and N2 gas adsorption analysis showed that pore structures (micropore volume, micropore surface area, meso-macropore volume, and meso-macropore surface area) changed significantly during hydrous pyrolysis. However, changes in pore structure were dissimilar among the four samples, which was attributed to different activation energies of organic matter. A thermodynamic fractal model showed a decrease in fractal dimensions of Utica, Monterey, and Excello after hydrous pyrolysis, indicating a decrease in surface roughness. The pore size heterogeneity in the Utica sample increased as hydrous pyrolysis temperature increased, whereas the pore size heterogeneity distributions in the Monterey and Excello decreased based on the N2 adsorption data