Vapor-liquid equilibrium data for C02 + ethanol mixtures at 314.5, 325.2, and 337.2 K and for C02 + 1-butanol mixtures at 314.8, 325.3, and 337.2 K have been measured by using a high pressure flow apparatus. The pressure In the experiments ranged from 4.633 to 11.776 MPa. Our results for the C02 + ethanol system are In good agreement with the recent results of Suzuki et al. and with the results of Panaglotopoulos. However, the results for the C02 + 1-butanol system are significantly different from those reported by King et al.

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As a complement to the bulk analyses presented in part 1 (Jennings, D. W.; Shaikh, A. Energy Fuels 2007, 21, 176-184), we report detailed compositional analysis of the organic acids from heat-exchanger deposits and produced water from an inverted steam-assisted gravity drainage (SAGD) bitumen production process. The current analyses were performed by ultrahigh-resolution negative-ion electrospray ionization Fourier transform ion cyclotron resonance mass spectrometry [(-) ESI FT-ICR MS] and reveal distributions of molecular weight, heteroatom content, aromaticity, and carbon number for several thousand organic acids in each sample. High mass accuracy combined with Kendrick mass defect analysis allows for assignment of a unique elemental composition, C c H h N n O o S s , to each mass spectral peak. Three-dimensional mass spectral images generated from the molecular formulas reveal compositional differences that may be rationalized on the basis of sample processing. In particular, we report lower overall heteroatom content, higher average carbon number, and lower aromaticity for early stage deposits and the produced bitumen compared to later stage samples that show increased water solubility. Little was previously known about those species other than the presence of organic acid/acid salt functionality. Moreover, we report the first in Vacuo isolation and tandem mass spectrometry of individual components of petroleum mixtures. Tandem mass spectrometry by infrared multiphoton dissociation of trapped ions indicates dicarboxylic acid structures for predominant C c H h O 4 and dicarboxylic acid structures with thiophenic sulfur for predominant C c H h SO 4 species. In this manner, we provide a highly detailed landscape for the organic acid content of inverted SAGD heat-exchanger deposits, to further illuminate the nature of fouling in those systems.

Heat-exchanger fouling is a severe operational problem in steam-assisted gravity drainage (SAGD) processes. In an effort to better understand which species are prone to deposit and gain insights into means for mitigating SAGD heat-exchanger deposition, analyses were performed on a series of heat-exchanger deposit samples from an inverted SAGD operation in Canada. Deposit samples were obtained from each of five heat-exchanger banks used in the operation of the facility: exchangers heating the produced raw bitumen reverse emulsion coming from the wells (two exchanger banks in series) and exchangers cooling separated produced water leaving the high-temperature separator (HTS) (three exchanger banks in series). The separated produced water leaving the facility HTS was also analyzed. The analyses focused on determining the overall inorganic and organic elemental compositions, as well as providing general information on the type of chemical species predominately present. The analyses performed on the deposits and solids from the produced water included (1) carbon, hydrogen, and nitrogen analyses, (2) X-ray fluoresence, (3) X-ray diffraction, (4) thermogravimetric analyses, (5) chloroform/methanol/toluene solubilities, and (6) Fourier transform infrared spectroscopy. Ion chromatography and inductively coupled plasma analyses were also run on the water sample. Analyses indicated preferential deposition of particular species and potential causes of deposition in certain exchangers. For the SAGD operation, at that time, a periodic slop-tank recycle containing warm lime softener sludge was indicated as a source of a significant amount of fouling in the heat exchangers handling the produced bitumen reverse emulsion and the initial exchanger cooling separated produced water leaving the HTS. High Mg +2 and Si +4 compositions were detected in these deposits. Magnesium silicates were indicated in Fourier transform infrared spectroscopy analyses. Deposition of additional other sand/silicates was also indicated. For the organic portion of these deposits, significant concentrations of organic acids and organic acid salts were indicated within the deposit hydrocarbons. Although all deposits contained both inorganic and organic components, the deposits in the last two exchangers cooling the produced water were found to be predominately organic. Significant concentrations of organic acids and organic acid salts were also indicated in these deposits. The indications of a significant organic acid/acid salt content led to collaboration work with the National High Magnetic Field Laboratory to study these components in detail. Electrospray ionization Fourier transform ion cyclotron resonance mass spectroscopy work performed at the National High Magnetic Field Laboratory is discussed in the part 2 companion paper (