Egyptian Oil Research Articles

Statistical analysis of Egyptian oil shale column flotation

ABSTRACT Evaluation possibility of a low-quality Egyptian oil shale from Wadii El-Nakhil, Red sea region as an alternative clean fuel by advanced flotation technique via column flotation was investigated. XRD analysis showed that the non-clay minerals associated with the oil shale sample include; quartz, siderite, apatite, anhydrite, and calcite. Column flotation experiments were carried out and results were analyzed according to screening designs which are used when numerous parameters would affect a particular process. Reduced three-factor interactions (3 FI) two-level factorial experimental design were employed to evaluate the effects of the seven independent parameters. Besides, the contour plots were used to summarize the optimum reaction factors leading to a predicted maximum kerogen grade of 52.35% and kerogen recovery of 78.41%. The calculated optimum parameters were 15% solid concentration, 0 cm/s superficial wash water velocity, 0.49 cm/s feed superficial velocity, 40 ppm frother concentration, 40 cm froth depth, 0.67 cm/s superficial air velocity and 0.5 kg/ton kerosene collector dosage. The confirmation tests, at optimum conditions as predicted from the contour plots, gave approximately the same grade and recovery of about 54% and 80%, respectively.

A laboratory investigation of carbon dioxide-enhanced oil recovery by focusing on CO2-oil physical properties

Carbon dioxide (CO2) miscible flooding has become an important method in enhanced oil recovery (EOR) for recovering residual oil. In addition it may help in protection of the environment as (CO2) is widely viewed as an important agent in global warming. Knowledge of the interactions between (CO2) and reservoir crude oil is very critical for any (CO2)-enhanced oil recovery (EOR) projects. This paper shows the effect of (CO2) miscible flooding application for Egyptian oil fields by swelling studies. The swelling test is a laboratory simulation of the process of injecting gradually different percentage of (CO2) gas into a reservoir containing under-saturated oil. The gas (injection solvent) can dissolve, causing the reservoir fluid to swell. This paper presents a summary of a wide range of laboratory tests conducted on ten different crude oils varying from 26.4 to 40.5 API. These were used to invested the use of (CO2) and its effect on parameters such as viscosity, density, gas solubility and swelling factor as a function of pressure at temperature from 620.3 to 706.0 °R.

Effects of Garlic Oils on the Fecundity and Hatchability of Callosobruchus maculatus L. (Coleoptera: Bruchidae)

Laboratory experiments were conducted to evaluate the efficacy of the three types of garlic oils; Sudanese, Chinese and Egyptian on the eggs of cowpea beetle Callosobruchus maculatus. Volatile oils from Sudanese and Chinese garlic were obtained by steam distillation and Soxhlet extraction using ethanol correspondingly, whereas Egyptian garlic oil was bought as a ready-made product. The oils were tested at concentrations of 0.01%, 0.1%, 1%, 5% and 10%, at exposure periods ranging from 24-72 hrs. Respective average number of eggs laid after exposure to the lowest concentration of Sudanese, Chinese and Egyptian oils were; 5.4, 4.0, 4.1 after 24 hrs; 0.7, 0.1, 0.1 after 48 hrs 0.2, 0.5, 0.5 after 72 hrs. The oils from the three garlic cultivars significantly reduced number of eggs laid with the highest dose (10%) caused complete inhibition of egg laying. Average number of eggs hatched when exposed to the lowest concentration (0.01%) were; 0.25 after one day and 1.00 after 7 days of exposure to Sudanese oil vapours, 0.00 after one day and 0.75 after 7 days of exposure to Chinese oil vapour and 0.00 after one day and 0.75 after 7 days of exposure to Egyptian oil vapour.

Comparative study for the volatile constituents and the antioxidant activity of the essential oils of dried Achillea fragrantissima cultivated in Madinah Monawara, Saudi Arabia and Egypt

ABSTRACT Hydrodistilled essential oils (HD) of dried aerial parts of Achillea fragrantissima cultivated in Egypt and Madinah Monawara, Saudi Arabia, and their volatiles extracted by solid phase microextraction (SPME) were analyzed using Gas Chromatography – Mass Spectrometry. Thirty – four constituents of the essential oil of Egyptian A. fragrantissima were identified, representing 90.15% of the total oil constituents, while SPME revealed 15 components constituting 94.72% of the volatile material. Santolina alcohol, artemisia ketone, α-thujone, 4(10)-thujen-3-ol, β-thujone, yomogi alcohol and trans-sabinyl acetate were the predominant components in both extracts, with quantities varying with extraction method. Many terpenes e.g. β-pinene, sabinene, α-terpinene, p-cymene, linalool, p-menth-2-en-1-ol, 4(10)-thujen-3-ol, borneol, carvone, p-menth-1-en-3-one, bornyl acetate and germacrene D, were identified for the first time. α-Thujone, 4-terpineol, trans-pinocarveol, and spathulenol were the major components among 42 identified components accounting for 93.65% of the total identified volatiles of Madinah hydrodistillate. Monoterpenes concentration was higher in Madinah SPME volatile extract than in HD essential oil. A. fragrantissima essential oil of Madinah exhibited higher antioxidant activity (IC50 1.09 mg/ml) than did Egyptian oil (IC50 1.72 mg/ml), consistent with the differences in phenolic content and volatile constituents identified in both oils.

Strength and ductility level earthquake design for Gulf of Suez oil platforms

Gulf of Suez area which characterized by a moderate seismic activity is consider as a very important area in Egypt. Nearly 75% of the national oil production is covered from this area. Seismic hazard (both probabilistic and deterministic) was carried out to study the possibility of earthquake damage in the area; a new seismic model was used taking into account the seismo-tectonic framework of the region. The hazard calculations utilized at strength and ductility level periods at the whole area of the Gulf of Suez. Fundamentally, the hazard calculations were performed at bedrock conditions, and the spectrum was estimated over the period range of 0.001–12 s. At Abou Zeniama area, where many oil platforms exist, the hazard was calculated at the sea floor, at depth 4.7 m and at depth 26.0 m. The maximum spectral accelerations at strength level earthquakes (SLEs) are found to be 0.260 (g), 0.203 (g), and 0.156 (g) for 90.48% chance, of non-exceedance in 50 years (return period 500 year) at sea floor, at depth 4.7 m and at depth 26 m, respectively. While the ductility level earthquake (DLE) are found to be 0.30 (g), 0.23 (g), and 0.18 (g) for 95.12% chance of non-exceedance in 50 years (return period 1000 year) at sea floor, at depth 4.7 m, and at depth 26 m, respectively. The deterministic hazard calculation was estimated at 50th and 84th percentile levels for the median peak ground acceleration. The study target initiated from the importance of studying the seismic hazard, SLE, and DLE in the area which contain most of the Egyptian oil industry with many off shore platforms.

The Effects of Transformational Leadership onthe Employees Change Readiness: the Moderating Role of the Incentive Schemes

Abstract: Nowadays, the dynamic and turbulent environment creates new business strategies and consequently thousands – if not millions – of change projects have been launched all over the world which aim to reform and catch the new modern world. The main corner stone for a successful change is the human being. Actually, human nature always tends for stability and resists change. But the question is; is it an option? The answer is quite clear, “It is not”. Change is inevitable and key factors that affect human readiness for change are important to be investigated and studied. Transformational leadership is one of these factors that may cause change in individuals and social systems, helping in growing and shaping the future success of the company. Also, incentive schemes which describe a system of rewarding success and effort in the workplace may influence the relationship between the transformational leadership and the employees' readiness for change. Therefore, the objective of this research work is to study the effect of transformational leadership on employees’ readiness for change and how the incentive scheme within organizations impacts the employees’ readiness for change. The Egyptian Oil & Gas sector was selected to be the case study for this research due to the fact that there are massive change projects covering such sector in Egypt. Mixed methods research - quantitative and qualitative methods- is the applied methodology for conducting this research as it provides a better understanding of the research problem than either of each alone. The hypotheses test showed that transformational leadership and all of its components; individualized consideration, intellectual simulation, inspirational motivation and idealized influence have a positive linear relationship with employee readiness for change. However, financial schemes only act as a moderator between transformational leadership and employee readiness for change but in a negative way, while the moral ones have no moderating effect on such relationship. The interviews explained this matter by clarifying that the financial incentives in the Oil and Gas sector follow a strict quota system due to budget limitations and in turn, influence negatively the employees' perceptions of unfairness concerning financial incentives distribution policy. Such perceptions impact significantly on their confidence in their managers and consequently affect negatively their readiness for change. Along with the unfair financial incentive schemes, there is no clear scheme of moral incentives in their organizations and that is why it has no impact on the employees' readiness for change. Finally, a well-structured and more efficient financial and moral incentives scheme is recommended to be applied in order to strengthen the impact of the transformational leadership on the employees' readiness for change.

Biodiesel production from castor oil in Egypt: Process optimisation, kinetic study, diesel engine performance and exhaust emissions analysis

In this study, biodiesel production from castor oil has been investigated. Five independent variables including; methanol to oil (M:O) molar ratio, catalyst concentration, reaction temperature, time and stirring rate have been chosen to investigate their effect on biodiesel yield. Response Surface Methodology (RSM) via Rotatable Central Composite Design (RCCD) has been used to evaluate the influence of the independent variables on the reaction response. Analysis of variance (ANOVA) has been used to investigate the adequacy of the predicted model. The optimum conditions for 97.82% biodiesel yield have been achieved at M:O molar ratio of 5.4:1, potassium hydroxide (KOH) catalyst concentration of 0.73%, temperature of 64 °C, time of 2.5 h and stirring rate of 320 rpm. The predicted optimum conditions have been validated with 0.59% relative error from experimental results. The kinetic calculations concluded that reaction is pseudo second order with reaction rate constant, activation energy and frequency factor of 0.16 M−1 min−1, 21.95 kJ/mol and 6.02 M−1 min−1, respectively. Finally, a case study investigating the performance and emissions on a direct injection (DI) diesel engine fuelled by biodiesel/petro-diesel blends (5, 10, 15 and 20% v:v) has been performed concluding significant reduction of greenhouse and toxic gases.

THE NEGATIVE IMPACTS FOR SUPPORTING ENERGY ON EGYPTIAN BALANCE OF PAYMENT IN THE TIME DURATION (FROM 2004-2014) AND SUGGESTING A RATIONALIZATION FRAMEWORK

This study drives at analyzing the negative impacts of supporting energy on Egyptian economy during the period from 2004-2014, suggesting a framework for rationalizing this energy. The energy problem is affecting all aspects in Egypt, the economic, social, and environmental aspects, in addition to risks the general budget and the balance of payment may be exposed to because of the increased governmental expenditure on supporting petroleum products and the natural gas which affects in turn other several fields such as education and health. The study sets a proposed framework for rationalizing and reforming support in Egypt. The study analyzes the negative aspects concerning the problem of supporting energy and the increase of the deficit of the state’s general budget, as it has moved from 43.3 milliard pounds in 2006/2007 to 71.2 milliard pounds in 2007/2008 at a 64% increase of the total deficit, turning from 54.7 milliard pounds in 2006/2007 to 61.1 milliard pounds at a 11.7% increase in the general budget and a 6.8% in total deficit of the budget (which is the highest globally). The researchers come to several results; that there is a significant correlation between increasing of importation and the exacerbation of the problem of supporting energy; as the deficit in the balance of payments has increased from 5.7 milliard dollars in 2004/2005 to 12.4 milliard dollars in 2007/2008 at 118% increase rate. The study recommends collecting Zakat money by the government (about 75 milliard pounds/per year) of the total value of Islamic deposits in banks (2.9 billion pounds) that equals 75 milliard pounds per year. The study counts on two integrated methods, the inductive method and the descriptive-analytical method. The (energy support) data is collected from the information available from annual reports of the Egyptian Oil Public Organization; while the (total economy) indicator data is obtained from the Central Authority for Public Mobilization and Statistics, and the (international data) is collected from the International Financial Statistics (IFS). THE NEGATIVE IMPACTS FOR SUPPORTING ENERGY ON EGYPTIAN BALANCE OF PAYMENT IN THE TIME DURATION (FROM 2004-2014) AND SUGGESTING A RATIONALIZATION FRAMEWORK This study drives at analyzing the negative impacts of supporting energy on Egyptian economy during the period from 2004-2014, suggesting a framework for rationalizing this energy. The energy problem is affecting all aspects in Egypt, the economic, social, and environmental aspects, in addition to risks the general budget and the balance of payment may be exposed to because of the increased governmental expenditure on supporting petroleum products and the natural gas which affects in turn other several fields such as education and health. The study sets a proposed framework for rationalizing and reforming support in Egypt. The study analyzes the negative aspects concerning the problem of supporting energy and the increase of the deficit of the state’s general budget, as it has moved from 43.3 milliard pounds in 2006/2007 to 71.2 milliard pounds in 2007/2008 at a 64% increase of the total deficit, turning from 54.7 milliard pounds in 2006/2007 to 61.1 milliard pounds at a 11.7% increase in the general budget and a 6.8% in total deficit of the budget (which is the highest globally). The researchers come to several results; that there is a significant correlation between increasing of importation and the exacerbation of the problem of supporting energy; as the deficit in the balance of payments has increased from 5.7 milliard dollars in 2004/2005 to 12.4 milliard dollars in 2007/2008 at 118% increase rate. The study recommends collecting Zakat money by the government (about 75 milliard pounds/per year) of the total value of Islamic deposits in banks (2.9 billion pounds) that equals 75 milliard pounds per year. The study counts on two integrated methods, the inductive method and the descriptive-analytical method. The (energy support) data is collected from the information available from annual reports of the Egyptian Oil Public Organization; while the (total economy) indicator data is obtained from the Central Authority for Public Mobilization and Statistics, and the (international data) is collected from the International Financial Statistics (IFS).

Integrated palynological, organic geochemical, and sequence stratigraphic analyses of the middle to upper Cenomanian hydrocarbon reservoir/source Abu Roash “G” Member: A depositional model in northwestern Egypt

Abstract The current investigation provides further insight into the petroliferous characteristics of the Abu Roash “G” Member, which is regarded as an important rock unit for the Egyptian oil industry. Forty-seven samples covering the “G” Member were selected from the BED 14-1 and BED 2-4 wells in the Abu Gharadig Basin and from the Abu Tunis 1X well in the Matruh Basin, both of which are located in the north Western Desert. An independent dating of the “G” rocks of BED 2-4 by benthic foraminifera and ostracods, in addition to palynological dating, suggests a middle-late Cenomanian age and provides the biochronostratigraphic framework for the sequence stratigraphic analysis. Analysis of the vertical distribution of particulate organic matter defines three palynofacies types (PF). PF-1 represents the basal “G”, where shales of the BED wells and calcareous shale of Abu Tunis 1X were deposited during a relative sea level rise in an outer middle shelf environment that experienced a notable high primary productivity. Prevailing reducing (suboxic-anoxic) conditions supported preservation of very high amounts of amorphous organic matter (AOM) in PF-1. PF-2 is equated to shales of the middle “G” of BED 14-1 and BED 2-4 and to calcareous shales and limestone of the upper “G” in Abu Tunis 1X. PF-2 was deposited during a relative sea level fall in an inner middle shelf setting under better-developed suboxic-anoxic conditions. PF-3 corresponds to the upper “G” of BED 14-1 and BED 2-4 and represents the shallowest setting, where sandy and silty shales were deposited during a pronounced sea level fall in an inner shelf environment. The same suboxic-anoxic conditions were prevailing during deposition of PF-3. Three bioevents were recorded, which could be of palaeoecological and/or biostratigraphic significance. These are Senegalinium aenigmaticum-Dinopterygium cladoides peak, Dinopterygium cladoides-Dinopterygium alatum peak, and an acme of Classopollis brasiliensis. Sequence stratigraphy of a transect of the four studied sections was carried out to understand the response of the particulate organic matter distribution and depositional system to the sea level changes. Three third-order, depositional genetic sequences were recognized and correlated with the global sea level curve (KCe 2, KCe 3, and KCe 4). The early highstand systems tract (eHST) of the genetically related KCe 3 in all wells is characterized by relatively rich organic matter, where combined remarkably low water circulation and insignificant dilution of organic matter with coarse terrigenous material probably supported good preservation of organic matter. Spatial distribution of the “G” rocks shows lateral facies changes. This was inferred from sedimentation of an organic-poor (avg. 0.8 TOC wt %), coarse clastic (sandy shales) facies in the studied area in Abu Gharadig Basin. Sedimentation changes laterally into a northeast and northwest organic-rich, finer clastic (shale, calcareous shales, and argillaceous limestone) facies in the western Matruh Basin. The robust anoxic conditions and very low dilution of organic matter by terrigenous influx enhanced the organic richness (avg. 2.4 TOC wt %) of these rocks, which resulted in the formation of promising hydrocarbon source rocks. Thus, for a successful hydrocarbon exploration in the north Western Desert, the promising source section of the “G” Member would be associated with shales, calcareous shales, and argillaceous limestone lithologies. Its depositional environment is mainly confined to outer middle and inner middle shelf settings that have widespread suboxic-anoxic conditions and show eHST pattern. In contrast, the regressive intervals that are denoted by the lowstand systems tract (LST) and/or the late HST (lHST) typify the relatively coarse clastics as good quality reservoir rocks that are characterized by poor organic richness due to dilution with terrigenous influx.

The effect of asphaltene content on predicting heavy dead oils viscosity: Experimental and modeling study

The viscosity of heavy dead oil is one of the most important governing parameters of the fluid flow, either in the porous media or pipelines, so it is of great importance to use accurate empirical correlation to estimate the heavy oil viscosity at various operating temperature. Published heavy oil viscosity correlations resulted in huge errors. The resulted deviations are attributed to the differences in the Asphaltenic content of crude oils and their dependence on operating temperature and density only. Therefore, we need to develop an accurate empirical correlation model that represents the heavy dead crude oil viscosity by adding different effective parameters as Asphaltenic content, oil density at operating temperature and oil molecular weight. In this paper, heavy dead oil empirical correlation has been developed using laboratory data (710 set point) of heavy oil samples that collected from different locations in Egypt. Heavy dead oil viscosity measurements operated at API gravity (22.79 > API > 12.36). Efforts are made to build a best-fit correlation by multiple least-square nonlinear regression analysis to find viscosity as a function of (Asphalten, TOper., API gravity, MWT and ρOper.temp.). Both statistical and graphical techniques were applied on hundred data point to evaluate this developed empirical correlation with literature ones and experimental data of Egyptian oil samples. The results show that the developed empirical correlation presents better accuracy and performance for predicting the heavy dead oil viscosity than those correlations in literature.

Upgrading of Egyptian Oil Shale Using Enhanced Gravity Separation

Egyptian oil shale from Wadii El-Nakhil, Red sea region was upgraded using enhanced gravity separation. The oil shale sample was characterized physically and chemically to determine its mineral content and characteristics. The sample includes quartz, siderite, apatite, anhydrite and calcite. The clay mineral is mainly represented by kaolinite while the organic matter is 30%. The ground sample (less than 50 microns) was classified into two fractions. The coarser was higher than 25 µm while the finer was less than 25 µm. The lower and upper levels of both the centrifugal force and water pressure have been suggested to construct the design for Falcon Concentrator type SB-40. The coarse concentrate of 42% kerogen with 94.35% recovery was achieved at 60 Hz (equivalent to G-force 176) and water pressure of 4 Psi from feed of 29% kerogen. The fine concentrate of 38.46% kerogen with 85.4% recovery was achieved at 70 Hz (equivalent to G-force 243) and water pressure of 2 Psi from feed of 33% kerogen.

Fingerprinting of biomarker characteristics of some Egyptian crude oils in Northern Western Desert as evidence for organic matter input and maturity level assessment

This study describes the fingerprinting of crude oils from different Egyptian oil formations using gas chromatography (GC) and gas chromatography mass spectrometry (GC–MS). The samples were obtained from Gindi, Abu El gharadig, south deep Abu El gharadig, Dahab- Merier and Faghur basins from Western Desert. Diagnostic biomarkers parameters applied in this study provide evidences about the source of organic matter, the depositional environment and maturity of the studied oils. The results showed that the crude oils of Faghur basin are believed to be originated from mixed source predominately terrestrial with chief contribution of clastic rocks deposited under oxic conditions. However, the crude oils from Gindi, Abu El gharadig, South deep Abu El gharadig and Dahab- Merier basins were generated from marine carbonate source rock deposited under anoxic depositional environment.

Influence of biodiesel from Egyptian used cooking oil on performance and emissions of small diesel engine

Influence of biodiesel from Egyptian used cooking oil on performance and emissions of small diesel engine

Study of Jojoba (Simmondsia chinensis) Oil by Gas Chromatography

The oil of Simmondsia chinensis (Link) CK Schneid (Simmondsiaceae) has been traditionally used in ethnomedicine because of its unique chemical constituents. This study aims to analyze the components of Egyptian Jojoba Oil (JO) and assess the differences between the Egyptian JO and that found in other parts of the world. The fatty acids and sterols profiles will also be determined by Gas Chromatography (GC). Jojoba seeds were subjected to hot extraction by solvent (hexane) followed by cold pressing extraction. Our results showed that the fatty acid Behenic acid methyl ester (C22:0) and Cis-13, 16 Docosadienoic acid methyl ester (C22:2) were in higher percentages within the Egyptian oil compared to JO found in other parts of the world. On the other hand, Egyptian oil was found to have lower percentage of the fatty acids; Eliadic acid, YLinolenic acid, Cis-8,11,14 Eieosatrienoic acid, and Lingocernic acid. Heneicosaoic acid was in much higher percentages within the Egyptian oil and the Egyptian JO does not contain Arachidic, Arachidonic Caprylic, Capric, lauric, Tridecanoic, Myristicor Palmitoleic acid. This study reports novel results clarifying the components of JO cultivated in Egypt under different environmental conditions to our knowledge such results have not been report befor

Crude oils geochemistry depended specific properties, metalloporphyrins, bulk compositions, and n-alkanes of some Egyptian oils in the Gulf of Suez, Egypt

ABSTRACTThe geochemical analyses of Specific gravity (API), sulfur content, nickel and vanadium, porphyrins, bulk compositions, and saturated fraction obtained from gas chromatography have been studied with the aim of throwing more light on the geochemical aspects of the crude oil formation, migration, and maturation. Seven samples were collected from Sudr, October, GS-283, Belayim land, Belayim marine, Kareem, and July oilfields in the Gulf of Suez. These samples are representative for the producing horizon zones of Rudeis and Nuhkul formations of Middle-Lower Miocene age ranging in depths from 1344 to 3558 m. The studied crude oils are classified into heavy and/or intermediate oils. The crude oils have high concentrations of nickel and vanadium contents. Vanadyl porphyrins indicate mature to moderately mature oils. A gross composition reveals marine organic sources. The n-alkanes and isoprenoids in crude oils are derived from marine organic matter, deposited under anoxic/hypersaline to oxic or carbonate environments associated with evaporate and carbonate depositional environment.

Environmentally weathered residues source diagnostic by high-molecular-weight polycyclic aromatic sulphur heterocycles

ABSTRACTHigh-molecular-weight polycyclic aromatic sulphur heterocycles (HMPASH) were applied in a forensic chemical analysis to identify the source(s) of environmentally weathered residues polluting the beaches of the Mediterranean city of Alexandria, Egypt, and to assess their weathering trends. The HMPASH were investigated by Fourier transform ion cyclotron resonance mass spectrometry in residues and an Egyptian crude as a possible source oil. The dibenzothiophenes/naphthenodibenzothiophenes (DBE 9/DBE 10) parameter indicated that two studied residues were likely to have originated from Egyptian crude oils, whereas the third residue could have had a foreign source. The residues displayed different stages of weathering. HMPASH having double bond equivalent (DBE) 1–5 were more influenced by weathering processes than those having DBE 6–17, probably because they are aliphatic sulphides and not aromatic compounds.

Some biosurfactants used as pour point depressant for waxy egyptian crude oil

ABSTRACTTwo bacteria (B1 and B2) were isolated from soil-contaminated sites. The surface properties of biosurfactants produced by these bacteria were determined. These bacteria were given a good resistance to NaCl concentration up to 20%. The surface activity was detected with maximum value at pH7 with B1, whereas B2 was not affected by the change pH (3–12). The biosurfactants of these bacteria were added as a mixture or individual to crude oil given the good result in reducing the pour point. The infrared spectrum of wax or asphaltene fractions of Egyptian crude oil untreated and treated with biosurfactants was detected.

Natural radioactivity and radiological hazard assessment of Egyptian oil ashes.

Oil fly and boiler ash samples were collected from the four major Egyptian power plants in order to determine their natural radioactivity. Secular equilibrium between (238)U and (232)Th and their decay products is significantly disturbed in oil ash samples. The (226)Ra/(238)U ratios were between 440 and 1993 with an average value of 801, indicating that the concentrations of daughters (226)Ra were very high compared to the parent (238)U in the oil ash samples. While, the average ratios for (210)Pb/(226)Ra in most samples were 1.19 ± 0.05, indicating a secular equilibrium in the (226)Ra-(210)Pb sub series. The natural radioactivity due to (238)U and (232)Th was found to be negligible. While the activity concentrations of (226)Ra ranged from 3205 to 12,320Bqkg(-1) with an average value of 9284Bqkg(-1), (210)Pb ranged from 5960 to 13,930Bqkg(-1) with an average value of 11,513Bqkg(-1). The results are compared with the reported data from other countries. The average value of radium equivalent activity was 9308 ± 2729Bqkg(-1), while the external and internal hazard indexes were found to be 25 ± 7 and 50 ± 15, respectively. All the studied radiological parameters were higher than the recommended limit by the IAEA in all ash samples.

Comparison of AAS, EDXRF, ICP-MS and INAA performance for determination of selected heavy metals in HFO ashes

A large amount of oil ash is generated in Egypt and Saudi Arabia each year as industrial waste. Most of these ashes are landfill and often lead to a dispersion of heavy metals in the surrounding groundwater and soil. In many countries, such as Egypt, little attention has been paid to the environmental effect of fly ash. In this study, the concentration of vanadium, nickel, iron, lead and zinc in oil fly and boiler ashes collected from six thermal power plants has been assessed with inductively coupled plasma mass spectrometry (ICP-MS), atomic absorption spectrometry, instrumental neutron activation analysis and energy dispersive X-ray fluorescence (EDXRF). Samples were digested using different acid and alkali fusion methods. EDXRF and ICP-MS were confirmed to be the analytical technique of choice for the precise and accurate determination of the major metals in oil ashes. Three internal reference materials from oil ashes were prepared and used to examine the capabilities and validations of the method. Vanadium (2.8–7.7wt.%), nickel (1.9–5.9wt.%) and iron (5.3–7.3wt.%) content were found to be within the average worldwide value, while lead (0.1–0.9wt.%) and zinc (0.6–4.2wt.%) were significantly high in Egyptian oil ash. Therefore, it was the first study which confirms the presence of high levels of lead and zinc in Egyptian oil fly and boiler ash. Saudi Arabian electrostatic precipitators (ESP) fly ash had lower V, Ni and Fe content (0.3–2.5wt.%). In addition, the concentration of Zn and Pb in ESP fly ash was significantly low (0.001–0.03wt.%) compared to Egyptian oil ashes.

Preliminary study of metalloporphyrins in some oil shales, red sea, Egypt

Occurence and distribution of metalloporphyrins were studied in asphaltene and maltene fractions of some Egyptian oil shales from the main producing mines (Abu-Shegeili, El-Beida, El-Nakheil and Abu-Tundub I, II) in red sea area (Fig. 1).Metalloporphyrins were extracted using adsorption column chromatography. The presence of Ni, Fe and Vo-porphyrins was monitored in each fraction by means of UV–Visible spectrometry, the result indicated that metalloporphyrins could be a mixture of Etio and DPEP types. Each fraction using UV–Visible spectrometry cannot differentiate between Ni and Fe porphyrins, so the extracted metalloporphyrins were subjected to purification and separation from each other by using thin layer chromatography (TLC).HPLC was used for fingerprinting Vo, Ni and Fe-porphyrins, it was found that the different porphyrins exhibited wide different chromatograms. HPLC technique could be used as a successful tool to characterize Fe and Ni-porphyrins.