الفهرس | Only 14 pages are availabe for public view |
Abstract The Quseir area became one of the most required and interesting places for further studies, because it represents the southern extension of the futuristic projects of Egypt (Golden Triangle), which will aid in the development of southern Egypt. There, the Late Cretaceous – Early Paleogene sedimentary sequence is represented by siliciclastics, phosphorites and carbonates. Areal distribution of these sediments may be related to the impact of tectonics and/or climatic effects. NW Pre-Cambrian strike slip movements, the so called Najd and later reactivation movements led to the formation of pull – apart subbasins. These sites represent the suitable places for the accumulation and/or local variation of the Late Cretaceous – Early Paleogene siliciclastics (sandstones and claystones), phosphorites and carbonates, which belong to the Nubia Sandstone, Quseir, Duwi, Dakhla, Esna and Thebes formations. At the Quseir area, the studied sediments were deposited under varied conditions comprising the fluviatile (F1-F2), tidal flat sediments (F3-F8) and open marine ones (F9-F16). The studied claystone samples have revealed their composition of smectite and kaolinite with variable proportions, in addition to quartz, calcite and/or dolomite. The higher percentage of kaolinite recorded in the Nubia Sandstone in addition to some samples of the Dakhla Formation. Its higher frequency in the former is quite normal because the Nubia Sandstone was suggested to accumulate under fluviatile conditions. In contrast, the unusual higher frequency of kaolinite, in the open marine Dakhla Formation may be attributed to the effect of intense weathering of the hinterland promoted by the impact of tectonics under warm conditions. The siliciclatics – bearing sequence included bentonitic horizons which recorded here - for the first time - intercalating the Quseir and Esna formations. The relative abundance of montmorillonite (smectite) was recorded in the mentioned formations to be more than 85%. Moreover, valuable (mineable) phosphorite beds occur intercalating the Quseir, Duwi and Dakhla formations. Also, thin phosphorite beds (< 20cm thick) have been recorded as interbeds within the above-mentioned rock units. Each high-grade phosphorite bed has experienced two successive stages of phosphogenesis, before its present state: the initial stage of phosphogenesis scenario started with sporadic phosphate peloids accumulated below fair-weather wave base under calm conditions, subsequently, the frequency and quantities of these peloids increased. The closing session of the scenario is characterized by fragmentation, reworking and redeposition of the peloids by high-energy events (i.e. storms). Prolonged action of the high-energy events promoted the mixing of peloids with other phosphatic components in crudely fining upward sequences. Both one event storm beds and amalgamated beds are common. SEM investigations indicate that algal bloom plays a relevant role in the origin of the Red Sea phosphorites, where they represent important sites for P – fixation and consequently a release of phosphorous. SUMMARY & CONCLUSIONS M.Sc. Thesis: Fatma Dardir Page 182 The noticeable variations in phosphorite thickness, P2O5 content and the hosting sediments (siliciclastics and/or carbonates) from one locality to another, within the Quseir area may be caused by syn-sedimentary local tectonics effects. The claystones collected from the fluviatile, tidal flat and open marine ones are used successfully in the synthesis of zeolite minerals. Faujasite, Sodalite and lithosite are the resultant obtained minerals from the hydrothermal treatment of the raw materials with either NaOH or KOH at 80 and 160 o C. The synthesized minerals were verified by XRD, FT – IR, SEM and Nitrogen sorption. Lithosite was synthesized here, for the first time by using KOH. The synthesized minerals have revealed an enormous removal capacity of organic matter (methylene blue dye) and heavy metals (Co, Pb, Cd, Zn and Cu) from the polluted water. Generally, their potentiality and efficiencies for the removal of heavy metals are higher than the organic matter. Spongy nano-porous Ni/Fe carbonate - fluorapatite was synthesized, for the first time using carbonate – fluorapatite of Zug El- Bohar locality. The product was verified by using XRD, FT-IR, SEM and EDX. It exhibits a spongy highly porous structure of nano and micro-pores and the average crystallite size is estimated by 8.27 nm. The suitability of the product for the removal of Cobalt (II), Copper (II) and Zinc (II) ions from water was considered as a function of contact time, adsorbent dose and initial concentration. The equilibrium time was obtained after 240 min for the uptake of Zinc (II) and Cobalt (II) ions while the adsorption of Copper (II) reaches the equilibrium after 120 min. The adsorption of the studied metal ions is represented well by a pseudo-second-order kinetic model, which reflects the chemical nature of the uptake process. The equilibrium studies were evaluated by using traditional models (Langmuir, Freundlich and Temkin model) and advanced models (monolayer model of one energy site and monolayer model of two energy sites) based on the statistical physics theory. The adsorption results fitted well with that of Langmuir isotherm model followed by Freundlich and Temkin models, which indicate the monolayer adsorption by nickel/iron carbonate - fluorapatite. The estimated qmax is 149.25 mg/g, 106.4 mg/g and 147.5 mg/g for the uptake of Zinc (II), Cobalt (II) and Copper (II), respectively. Based on monolayer model of one energy and monolayer model of two energies, the number of receptor adsorption sites, number of adsorbed ions per site, average number of occupation sites, monolayer adsorption quantity and the total saturation adsorption quantity were calculated for the first time for such materials. Spongy carbonate-fluorapatite loaded by nickel and iron was synthesized, here, for efficient conversion of waste cooking oil into biodiesel. The catalyst was synthesized through the dissolution of phosphorite in nitric acid, and then nickel chloride was dissolved in the separated filtrate solution. Then the catalyst was precipitated utilizing ammonia solution and heated at 150oC for 12h. The product exhibits a pronounced spongy porous structure and contain about 8% iron and 3% nickel metals. The suitability of the product as a catalyst in the conversion of waste cooking oil into biodiesel was studied and the biodiesel yield was obtained |