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    Calculation of higher heating values of hydrocarbon compounds and fatty acids
    (TAYLOR & FRANCIS INC, 2018) Demirbas, Ayhan; Ak, Namik; Aslan, Avni; Sen, Nejdet
    Hydrocarbon compounds are formed by carbon and hydrogen elements. The higher heating values (HHVs) of the hydrocarbon compounds can be calculated based on the carbon (C) and hydrogen (H) contents of the chemical structures. HHVs (MJ / kg) as a function of the carbon (C) and hydrogen (H) fractions of N-saturated hydrocarbons can be calculated by the following equation: According to this Equation, the HHV is a function of the percentages of the carbon (C) and hydrogen (H) of pure n-saturated hydrocarbon compounds. This Equation represents the correlation obtained by means of regression analysis. It is found that the calculated values shows mean difference of 0.18%. The correlation coefficient is 0.9955.HHVs as a function of the iodine value (IV) and the saponification value (SV) of fatty acids can be calculated by the following equation: HHV(MJ/kg) = 49.43 - 0.015(IV)-0.041(SV)
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    Gasoline- and diesel-like products from heavy oils via catalytic pyrolysis
    (TAYLOR & FRANCIS INC, 2017) Demirbas, Ayhan; Al-Ghamdi, Khalid; Sen, Nejdet; Aslan, Avni; Alalayah, Walid M.
    Heavy oil is less expensive than light crude oil, but heavy oil is more expensive to obtain light oil products. Conventional light crude oil resources are decreasing, therefore heavy oil resources will be needed more in the future. There are huge differences from field to field for heavy oil deposits. In terms of final productive use, heavy oil is considered as an unconventional resource. Heavy oil upgrading depends on four important factors: catalyst selection, heavy oil classification, process design, and production economics. Heavy and extra-heavy oils are unconventional reservoirs of oil. Globally, 21.3% of total oil reserves are heavy oil. Heavy oil is composed of long chain organic molecules called heavy hydrocarbons. The thermal degradation of the heavy hydrocarbons in heavy oil generates liquid and gaseous products. All kinds of heavy oils contain asphaltenes, and therefore are considered to be very dense material. The most similar technologies for upgrading of heavy oils are pyrolysis and catalytic pyrolysis, thermal and catalytic cracking, and hydrocracking. The amount of liquid products obtained from pyrolysis of heavy oil was dependent on the temperature and the catalyst. Pyrolytic oil contains highly valuable light hydrocarbons as gasoline and diesel components range. The constant increase in the use of crude oils has raised prices of the most common commercial conventional products and consequently seeking for new alternative petroleum resources, like some unconventional oil resources, becomes an interesting issue. The mass contents of gasoline, diesel, and heavy oil in the crude oil are 44.6%, 38.3%, and 17.1%, respectively. The gasoline yield from the heavy oil catalytic (Na2CO3) pyrolysis is higher than the diesel efficiency for all conditions. The yield of gasoline products increases with increasing pyrolysis temperature (from 230 degrees C to 350 degrees C) and percentage of catalyst (from 5% to 10%). The yields of gasoline-like product are from 21.5% to 39.1% in 5% catalytic run and from 32.5% to 42.5% in 10% catalytic run. The yields of diesel-like product are from 9.3% to 29.8% in 5% catalytic run and from 15.5% to 33.7% in 10% catalytic run.