فهرست مطالب

Progress in Chemical and Biochemical Research
Volume:3 Issue: 1, Feb 2022

  • تاریخ انتشار: 1398/11/12
  • تعداد عناوین: 9
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  • Nabil Bader *, Aya Elmajbry, Zainab Al Borki, Aziza Ahmida, Abdalla Geath Pages 1-6
    Potentiometric titrations have been used to calculate the dissociation constants of Hippuric acid and its stability constants with Cu(II), Ni(II), Zn(II), and Pb(II) ions in ethanol-water mixed solvent system at different temperatures, and constant ionic strength of 0.1M solution sodium nitrate. The order of the stability constants of metal complexes at 298 K with respect to ligand was found to be Cu(II) > Pb(II) > Zn(II) > Ni(II). Effect of temperature on stability of hippuric acid complexes with Cu(II) and Pb(II) has been studied in order to calculate the Gibb`s free energy and enthalpy of the complex formation reaction, the results showed that coordination process is spontanous and exothermic. Effect of solvent ratio has been studied only for Cu(II) complex and the dissociation of hippuric acid at given added different ratios decreases on the following order 75% > 50%.
    Keywords: Hippuric acid, Metal complexes, stability constant, mixed solvent system
  • Amir Samimi *, Kasra Kavousi, Soroush Zarinabadi, Alireza Bozorgian Pages 7-19
    Increasing the capacity of Gasoline Production Plant (G.P.P) will cause problems such as the increase of pressure downfall, reduction of output pressure of circulating gas compressor, increasing the thermal load of the re-boiler furnaces of unit towers, increase of the eventuality of formation green oil in vessels, increase of the eventuality of coke formation on the catalyst and eventually reducing the catalyst life span. In this research, operating conditions have been investigated that indicates the increase of the petrochemical feed with the design capacity of 71,000 barrels per day, to the 75,000 barrels per day. The results indicate that with increasing feed, the entrance temperature and pressure to the unit reactor should be increased. According to the obtained results the best temperature (in Feed) is 525 °C, output pressure of circulating gas compressor is more than 22 ton/hr and the circulation of catalysis range is 750-950 kg/hr, the Octane Number will be a Constant Rate 95 and the amount of Coke Formation in all Conditions 3.5-4.3%. The outcomes also show how this approach can be used to gain insight into some refineries and how to deliver results in a comprehensible and user-friendly way.
    Keywords: Catalyst, circulating gas, Coke, green oil, stabilizer
  • Nguamo Surma *, Godwin Ijuo, Blessing Ogoh-Orch Pages 20-30
    ABSTRACTThis study was carried out in order to obtain useful gases from waste polyethylene of high density polyethylene (HDPE) at low temperature pyrolysis. This was carried out by adapting a cylindrical pressure cooking pot of height 30.00 cm with an internal diameter 31.50 cm. The pyrolysis reaction was carried out with the influence of Fluid Catalytic Cracking (FCC) catalyst. The gases evolved during the pyrolysis reaction were collected using Tedlar bags and analysed using a BUCK 530 Gas Chromatograph. The pyrolysis reaction with fresh FCC catalyst at 150 °C and 250 °C using catalyst/sample ratio of 1:8 showed aliphatic hydrocarbons in the range of C1-C9 with total concentrations of 84.3969 and 526.4070 ppm respectively. The corresponding values obtained at 150 °C and 250 °C for HDPE using catalyst/sample ratio of 1:16 were obtained as 495.4315 and 385.5101 ppm respectively. The reaction with spent FCC catalyst at 150 °C and 250 °C using catalyst/sample ratio of 1:8 gave the total concentrations of 112.7276 ppm and 87.3531 ppm respectively. The corresponding values obtained at 150 °C and 250 °C using catalyst/sample ratio of 1:16 were 116.9178 and 109.4314 ppm respectively. Production of useful gases from waste polyethylene gave reasonable amounts of gaseous products which can serve as feed stock and as fuel gas.
    Keywords: Pyrolysis, HDPE, FCC catalyst, Fuel gases
  • Alireza Bozorgian, Zahra Arab Aboosadi *, Abolfazl Mohammadi, Bizhan Honarvar, Alireza Azimi Pages 31-38
    Natural gas and crude oil in natural underground reservoirs are in contact with water. Stability of these compounds at the presence of both components and complete dependence on the host molecules by forming holes in their guest molecules are replaced. There are many gases such as methane, ethane, propane, carbon dioxide, hydrogen sulphides that can play the role of guest molecules. The natural gas hydrate formation in different sectors of the oil and gas industry in downstream processes causes the production to stop or decrease. Therefore, the need to know the causes and conditions of hydrate formation is strongly felt. In this study, Van der Waals and Platteeuw model was used to predict hydrate formation conditions. The prediction of hydrate formation conditions needs equilibrium fugacity of gaseous components, and for the equilibrium molar component of water.
    Keywords: Naturl Gas, hydrogen, molar component of water, Crude Oil
  • Akunna Stella-Marris Ogbuagu, Chinedu Innocent Okoye * Pages 39-45
    The physicochemical characterization of n-hexane extracted oil of avocado (Persea americana) seed was carried out according to American Organization of Analytical Chemists (AOAC)/IUPAC standard methods. The result of the analysis showed that the oil sample contains an acid value of 1.542 mg/g, iodine value 127.40 g/100g, saponification value 196.35 mg/g and peroxide value 4.80mg/g, as well as specific gravity (0.8627), flashpoint (288oC) and relative viscosity (24.69 Cst.). This indicates that the oil can be used industrially for various purposes, including food processing, cosmetics etc
    Keywords: Persea Americana, Oil yield, Physicochemical properties
  • Amir Samimi *, Soroush Zarinabadi, Alireza Bozorgian, Ahmadreza Amosoltani, MohammadSadegh Tarkesh Esfahani, Kasra Kavousi Pages 46-54

    The presence of H2S and CO2 is unfavorable in many processes and flows, particularly in natural gas flows. Therefore, removing this gas is one of the important issues in many systems. One of the most widely used techniques is the use of membrane. Therefore, the gas that passes through the membrane has low pressure. Membrane system is used to absorb a high volume of CO2. The factors needed for this kind of separation include gas composition, pressure, and temperature difference. An enhanced electrochemical membrane can also be used with coal gas to separate acid gases. Hydrogen is so rich in this process in which cathode and sulphur steam are produced and then exited. Granular activated carbon (GAC) can be used as supporting material to absorb H2S. The advantages of this method are including high capacity for H2S absorption and gas emission. Removing the H2S from waste gases or natural gas with high densities is done via bio-filter in this system. Granular activated carbon can be used as a supporting material to stabilize the microorganisms. Principal properties of the supporting material are including the mass density, the area of special surface, and the amount of its pH. This research discusses the membrane technology in removing the acid gases in the oil technology.   © 2020 by SPC (Sami Publishing Company), Reproduction is permitted for noncommercial purposes.

    Keywords: Membrane, Nano-filtration, acid gas, pressure, Oil Industry
  • Haniyeh Shamsin Beyranvand, Masoomeh Mirzaei Ghaleh Ghobadi *, Hamid Sarlak Pages 55-63
    Fossil fuels are the main source of CO2 emissions into the atmosphere, which are sources of air pollutants. Environmental research has confirmed that atmospheric CO2 concentration has risen from 280 ppm in 1800 to 358 ppm in 1994 (an increase of 27.86%). Russia, the United States, China, the rest of the Asian countries, Latin American countries, and African countries accounted for 27, 22, 11, 13, 4, and 3% of the total global CO2 production, respectively. Various processes based on hydrogen sulfide and other acidic gases such as carbon dioxide, carbon disulfide, mercaptans, and carbonyl sulfide have been introduced for natural gas sweetening. One of these processes involves the use of solvents. In the present research, a device that measures solubility of gases in liquids was employed to measure solubility of CO2 in solvent DEEA in the presence of TiO2 at different solvent concentrations (10, 15, 20% w/w), various pressures (5, 10, and 15bar) and different TiO2 concentrations (0.05 and 0.1% w/w) at ambient temperature. Results showed that solubility increased from 25.8 to 42.4% v/v at constant pressure and without the presence of a nanoparticle in the absence of TiO2 at solvent concentrations ranging from 10 to 15% w/w. At a constant concentration of the solvent (15% w/w), solubility increased from 31.8 to 36.7% when the pressure was raised from 10 to 15 bar. Moreover, solubility increased from 32.7 to 36.7% v/v at constant solvent concentration (15% w/w) and pressure (15bar) when TiO2 concentration was raised.
    Keywords: Solubility, Titanium dioxide nanoparticle, Carbon dioxide, Diethyl Ethanolamine
  • Larisa Birichevskaya, Margarita Vinter, Natalia Litvinko, Anatoli Zinchenko * Pages 64-73
    A series of conjugates of pharmacologically promising modified nucleosides with phospholipid was synthesized. Some liponucleotides were originally produced. Soybean lecithin served as the donor of phosphatidyl residue. Phospholipase D from strain Streptomyces netropsis BIM B-428D was engaged as biocatalyst in transphosphatidylation reaction. The yield of liponucleotide synthesis reaction varied in the range 44–95 mol% depending on the acceptor of phosphatidyl residue. 65 mg (about 68 µmoles) of pure phosphatidylclofarabine was recovered by chromatography on silica gel column, resulting in 68 mol% yield calculated from the amount of modified nucleoside supplied into the reaction mixture.
    Keywords: Phospholipid prodrugs, Streptomyces netropsis, Enzymatic transphosphatidylation, Modified nucleosides, Phosphatidylclofarabine
  • Kaana Asemave *, D. O. ABAKPA, T.T. LIGOM Pages 74-80
    The ability of bacteria to develop resistance to many antibiotics cannot be undermined given the multifaceted health challenges in the present times. For this reason a lot attention is on botanicals and their products in search of new antibacterial agents. On the other hand, mango kernel oils (MKO) can be heavily valorized by taking advantage of the myriads bioactive phytochemicals it contains. Herein, we buttressed the use of MKO as bioactive agent against bacteria. The MKOs for the study were extracted by soxhlet means with ethanol and hexane for 4 h from 3 different mango kernels, namely; “local” (sample A), “julie” (sample B) and “john” (sample C). Prior to the extraction, ground fine particles of the kernels were obtained from the seed kernels dried in oven at 100 OC for 8 h. Hexane gave higher yield of the oils than ethanol. It was also qualitatively confirmed that the mango kernel oils contain some phytochemicals such as phenol, quinone, saponin and terpernoid. The results of the antibacterial activities of the MKO against both gram positive (staphylococcus aureus) and gram negative (pseudomonas aeruginosa) at different concentrations showed that the oils extracted with ethanol gave better antibacterial properties than those of the hexane. More so, the bioactivities were best with the local mango kernel oil. Indeed this work has completely validated the previous claim that MKOs are effective antibacterial agent. Thus, these oils (especially the ethanol-derived ones) can be used as bacteriostatic and antibacterial agent in say food, cosmetics and allied industries.
    Keywords: Bacteria, Mango, kernel, Oils, phytochemicals