فهرست مطالب

Chemical Methodologies
Volume:5 Issue: 5, Set-Oct 2021

  • تاریخ انتشار: 1400/06/14
  • تعداد عناوین: 9
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  • Zaydoon Kh. Kuraimid * Pages 367-372
    De-emulsifiers are one of the important industrial additives used commonly in petroleum industry in order to separate the salt water from crude oil essential the wet crude oil fields in south oil company (B.O.C) in Iraqi fields. De-emulsifiers activities due to the ability of these additives for breaking the thin film between dispersed phase and continuous phase globules in order to obtain two immiscible phase via the adsorption mechanism of the surfactants. In the present study has prepared local demulsifies by synthesis Gemini surfactants bis (Quaternary ammonium salt). The local de-emulsifier was assess in the laboratories of South Oil Company (B.O.C) Comparison with the results of commercial de-emulsifier (A), where the local material efficiency was higher than the important commercial (A) adopted in the B.O.C by bottle Test and later was produced (26) barrels of material prepared and evaluated in AL-SHAMIA Degassing station in Iraqi South Rumaila in (B.O.C). Where, evaluated the local de-emulsifier in the fields and show the positive results, this describes the evaluation of field emulsifying the local material in this study with lost cost of preparation of a one barrel about 500$ in the time that the cost of one barrel of commercial de-emulsifier is 1000$. The assessment was in the conditions of commercial de-emulsifier, depending on the natural of Dehydrator and Desalter in addition of the effective Dose is 25ppm and by 100% separation efficiency in same fresh oil source. The efficiency of local de-emulsifier studied Varity of parameters like: Temperature and the time required to separation function of the Dose. The field evaluation conditions of local de-emulsifier were under control outside of the oils (fresh) of D2 (Desalter) of isolation units to examine all of the water and salt content of crude oil. This was prepared for export according to the approved evaluation criteria compared with the commercial de-emulsifier imported and used in the oil sector.
    Keywords: Demulsifiers, water-in-oil emulsions, demulsification
  • Ali Moghaddam, HassanAli Zamani *, Hasan Karimi Maleh Pages 373-380

    Monitoring tamoxifen as an anticancer drug with high side effects is so important in the chemotropic process. In this regard, a fast and simple electrochemical sensor was fabricated using a carbon paste electrode (CPE) modified with 1-octyl-3-methylimidazolium chloride (OMIC) and Fe3O4/graphene nanocomposite and utilized for tamoxifen monitoring. Fe3O4/graphene nanocomposite (Fe3O4-GR) was synthesized by a one-pot synthesis approach, following by then characterized by FESEM and EDS methods. The Fe3O4-GR/OMIC/CPE offered catalytic activity on the redox reaction of tamoxifen and enhanced its oxidation current about 4.59 times. Moreover, the high electrical conductivity of mediators aided the reducing the oxidation potential of tamoxifen (about 80 mV) compared with the unmodified electrode. In addition, Fe3O4-GR/OMIC/CPE showed a linear dynamic range of 0.01 µM – 150 µM with a detection limit of 7.0 nM for sensing of tamoxifen using the square wave voltammetric method. Furthermore, Fe3O4-GR/OMIC/CPE displayed a superior ability for sensing tamoxifen in real samples with an acceptable recovery range. In brief, Fe3O4-GR/OMIC/CPE provided good selectivity for sensing f tamoxifen in an aqueous solution in the presence of organic and inorganic interferences.

    Keywords: Tamoxifen, 1-octyl-3-methylimidazolium chloride, Fe3O4, graphene nanocomposite, Sensor
  • MohammadSaleh Samie Adel, Elham Ameri * Pages 381-396

    This study investigated the influences of n-pentanol, n-butanol, and isobutanol on the calculated cetane index (CCI), density, boiling point of mid-boiling point (T50), flash point and pour point followed by studying individual effects of isobutanol, isobutanol + nitromethane, and 2-ethylhexyl nitrate (EHN). The simultaneous effects of isobutanol + nitromethane + EHN addition on the properties of the diesel fuel were studied, too. The results showed that the addition of isobutanol would tend to better properties of blended diesel fuel (BDF). Increasing nitromethane concentration in the fuel could enhance CCI, flash point, and viscosity for 3.29 %, 11.29 %, 2.56 % whereas no significant effects on the density and pour point were observed. Low EHN’s concentration firstly increased the CCI and volatility whereas further increase would lead to a reduction in a manner that the BDF with 0.02 vol. % of EHN exhibited 2.57 % and 3.59 % increases for CCI and boiling points, respectively. The addition of EHN to the diesel would tend to a decrement in pour point and viscosity as well as an increase in the flash point and density. Accordingly, the BDF comprised of 2 vol. % of isobutanol (80 vol. %) + nitromethane (20 vol. %) and 0.02 vol. % of EHN was found to be the optimum composition of final BDF. The addition of isobutanol + nitromethane + EHN (INE) led to increase CCI and significant decline volatility, flash and pour points, density, and viscosity of the diesel fuel, significantly.

    Keywords: Cetane improver, Flash point, Boiling point
  • Maryam Ebrahimi, Hadi Beitollahi * Pages 397-406
    Isoproterenol is an important catecholamine-based drug that is widely used in the treatment of heart disease. The present paper introduced one of the new modifications for the surfaces of glassy carbon electrodes (GCEs) using the CuO nanoflowers (CuO NFs) for determination of isoproterenol. Electrochemical properties of the CuO NFs/GCE for detecting isoproterenol were tested using the cyclic voltammetry (CV), chronoamperometry (CHA) as well as differential pulse voltammetry (DPV). Electrochemical studies demonstrated an efficient isoproterenol oxidation, with enhanced peak current from 2.9 µA to about 10.0 µA (3.4% increase) and decreased peak potential from 500 mV to about 300 mV. The linear response for the determination of isoproterenol was obtained in ranges for concentrations between 0.3 and 450.0 μM under the most proper conditions and the limit of detection (LOD) equaled 0.09 μM. Also, the modified electrode is utilized for simultaneously determining isoproterenol and theophylline using DPV. The proposed CuO NFs/GCE sensor was effectively employed for the isoproterenol and theophylline detection in the isoproterenol ampoule and urine samples.
    Keywords: glassy carbon electrode, CuO nanoflowers, Isoproterenol, Theophylline
  • Sajedeh Salaria, Hadi Beitollahi * Pages 407-415
    We applied GCE modified with Ce3+-NiO hexagonal nanoparticles (Ce3+-NiO HNPs) for preparing methyldopa electrochemical sensor. Electrochemical study of the modified electrode showed that within the optimal conditions of phosphate buffer solution (PBS) at a pH of 7.0 in CV, oxidation potency of methyldopa decline to ~100 mV at the modified electrode in comparison with an unmodified GCE. The sensor exhibits a sensitive response to methyldopa in range between 0.1 and 80.0 μM with a limit of detection (LOD) equal to 0.03 μM. In addition, as sensing materials for simultaneously determine hydro-chlorothiazide and methyldopa, Ce3+-NiO HNPs/GCE, exhibited high sensitivity. The defined and separated oxidation peaks of a mixture of methyldopa and hydrochlorothiazide were obtained with significant peak potential differences of 390 V. The proposed electrochemical sensor was employed in analysis of both drugs in the real specimens.
    Keywords: glassy carbon electrode, Ce3+-NiO hexagonal nanoparticles, Methyldopa, Hydrochlorothiazide, Electrochemical sensor
  • Raed M. Muhiebes *, Entesar O.Al Tamimi Pages 416-421

    In this research new creatinine Schiff bases (1a, 1b, and 1c) were synthesized from the reaction of aromatic aldehydes (4-nitrobenzaldehyde,4-amino benzaldehyde, and cinnamaldehyde) with creatinine, in few drops of glacial CH3COOH as a catalyst in C2H5OH. Then, seven-member rings were prepared (oxazepine) (2a-4c) on creatinine form treatment of imines with (phthalic, maleic, and succinic anhydrides. Synthesized compounds were identified by IR, melting point, and 1H-NMR of some of them. Some of the prepared compounds were studded with antioxidant activity.

    Keywords: Schiff base, oxazapane derivatives, Antioxidant activity
  • Arash Vojood, Mohammad Khodadadi Moghaddam *, Gholamreza Ebrahimzadeh Rajaei, Sahar Mohajeri, Ali Shamel Pages 422-432

    In the present paper, the Formose reaction is investigated to produce polyols in the presence of two different catalysts at different pHs. The Formose reaction mechanism is the same as aldol condensation, which occurs in alkaline media and is accelerated by the presence of a heterogeneous catalysis. The products observed in the reaction medium are ethylene glycol, and glyceraldehyde. The present study shows that in the presence of fumed silica catalyst, increasing the pH from 7.6 to 9.3 reduces the production of ethylene glycol; however, it increases the conversion of ethylene glycol to glyceraldehyde. As a result, the amount of ethylene glycol in the reaction mixture decreases compared with neutral pHs. Nevertheless, the selectivity of the reaction to the production of glyceraldehyde increases. The same result can be observed when using montmorillonite as another heterogeneous catalyst. The difference is that the montmorillonite catalyst has less ability to accelerate the reaction than fumed silica. Also, at pH around 9 and above, practically no product is observed in the reaction medium.

    Keywords: Formose reaction, Glyceraldehyde, Fumed silica, Montmorillonite, Catalyst
  • K. Karatayeva *, G.Myrzagereikyzy, B. Suleimenova, Z. K.Salykbayeva, V. Мakhatova, A.Yerekeshova, G. K. Nauryzbayeva, A. S. Khairullina Pages 433-445

    Maintaining pump operation in the best efficiency zone (BEZ) is one of the most important tasks of the control system. The main management tasks include detecting work outside the BEZ, preventing actions that may move the work point to undesirable areas, and regulating pumping parameters to keep work within the recommended limits. Thanks to the process control architecture of pump systems that use PLCs and programmable frequency converters, new algorithms can be implemented on these devices. This study provides suggestions for using sensor data, internal frequency converter parameters, or pump performance data from performance graphs for new control algorithms. For this purpose, the methodology of predictive control and performance monitoring were described. Pump operation outside BEZ and related phenomena were considered. The proposed algorithm for high-efficiency pump control in certain speed ranges were elaborated. Simulation of test runs of a pumping system relied on computer simulation tools modeling and software for VSD selection. Experimental tests were also introduced on a laboratory installation that simulates a pumping system.

    Keywords: Pumping system, efficiency zone, pumping parameters
  • Hossein Peyman *, Hamideh Roshanfekr, Arash Babakhanian, Hadi Jafari Pages 446-453
    In this study, a PVC membrane electrode was modified by a derivative of lawason that is a neutral ionophore for Cd (II) determination in alloy and wastewater as real samples. The modified electrode showed a linear electrochemical response to Cd (II) concentration between 5.0×10−8 to 1.5×10−1 molL-1 (LOD = 2.51×10−8 molL-1). In selecting and determining the level of an effective composite of the membrane, the highest results were achieved in the membrane composition 33% PVC, 64.0% TEHP, 1.5% NaTPB, and 1.5% ionophore. The time it takes for the response to reach its maximum and remain stable at this electrode is very favorable (response time < 12 s). The responses of the electrode in consecutive uses for two months did not deviate significantly. In investigating the disturbance of other ions and compounds in the measurement of cadmium, the designed electrode had a very good selectivity for cadmium. The best conditions for measuring cadmium with this electrode are in an acidic environment (pH range of 2.8–6.5). In this research, potentiometric titration with the use of chromate as titrant was used in water and alloy samples.
    Keywords: Cd (II) determination, Ion-selective electrode, PVC modified electrode, Lawson