الفهرس 
IntroductionOnly 14 pages are availabe for public view
 |  | from | 172 |  |  |
| | | from | 172 | | |
Abstract
The thesis is consisting of four Chapters, concerned with the fabrication of new agar-CMC-silver (AG-CMC-Ag NP) nanocomposite by surface modification of cellulose (extracted from Egyptian macroalga Ulva fasciata) to carboxymethylcellulose (CMC) anchored on silver nanoparticles (Ag NP), followed by agar (AG; extracted from Gelidium crinale). Batch studies were applied to evaluate the efficacy of these biomaterials to remove methylene blue (MB) cationic dye as well as crude and waste diesel oil from wastewaters. The characteristics of fabricated biomaterials (CMC, CMC-Ag NP and AG-CMC-Ag NP) were enlightened by using Fourier transform infrared (FTIR), UV-vis, X-Ray powder diffraction (XRD), transmission and electron microscopy-energy dispersive X-Ray (SEM-EDX) spectroscopy, thermogravimetric (TGA), and the zero-point charge of pH (pHZPC) measurements. The adsorptive performance of methylene blue (MB) and diesel oil from aquatic medium onto AG-CMC-Ag NP was studied with the multifarious parameters of pH, contact time, temperature, amount of sorbent and initial MB dye or oil concentration. The studies associated with adsorption isotherms, kinetics, and thermodynamics were carried out. The dye concentration in supernatant solution was determined spectrophotometrically at ʎmax 665 nm. In addition, the adsorption capacity of crude or waste diesel oil onto aerogel AG-CMC-Ag NP nanocomposite was determined by calculating the weight of sorbent before and after oil absorption. This Thesis consists of four main chapters are; Chapter I: Introduction This part is dealing with dyes and diesel oils as pollutants, which have received a great attention as a main source of water contamination, causes serious ecology damage and health problems. Moreover, large number and types of dyes in industrial wastewater cannot be degraded easily through conventional wastewater treatment based on their complicated molecular structures. Thus, dye removal from industrial wastewater is a fundamental issue and appropriate wastewater treatments should be done to decrease the environmental impact. For removal of dyes from wastewater, large number of wastewater treatment strategies have been applied, such as chemical and biological methods, including coagulation/ flocculation, electro-chemical degradation, photocatalytic degradation, advanced oxidation, ozonation, membrane filtration, and liquid–liquid extraction. To purify wastewater from colored impurities, one of the most promising wastewater treatment strategies is adsorption, which is convenient technique due to the high removal efficiencies, low cost, and the flexibility in the design, ease of operation and insensitive to toxic substances. For the removal of dyes from aqueous media by adsorption processes, various sorbents of organic and inorganic sources with sizes ranging from nano to micro have been reported. In addition, numerous kinds of sorbents, including functionalized membranes, carbon-based materials, nanocomposites, porous polymers, natural clay, fibers, gels, bio-sorbents deriving from renewable and biodegradable cellulose, and surface modification cellulose with functional polymers (with carboxylic, amide and/or amino groups) have been developed to remove dyes. This chapter is also concerned with a literature survey on methylene blue (MB) as one of the cationic dyes which has wide range of applications (colouring agent in chemistry, biology, medical fields, and dyeing industries, such as chemical indicators, ink production, textile, paint and paper). The biobased solid consists of sodium carboxymethyl cellulose and their derivatives as sorbents to remove MB dye from wastewater. In addition, oils, which cause ecology damages in aquatic flora and fauna microorganisms, plant, animal, as well as mutagenic and carcinogenic for human. They discharge from different sources to form a layer on the water surface, decreasing the dissolved oxygen. Oil layer leads to reduce the dissolved oxygen levels in water, which are difficult to be oxidative for microbial on hydrocarbon molecules and cause environmental deteriorations to water bodies. The effective methods for rapid and selective collection and removal of oils from wastewater, such as oil skimmers, booms, bioremediation, controlled burning, physical diffusion, solidifiers, dispersants, and adsorption have been reported. Adsorption as the most effective for oil/water removal due to the low cost, easy recyclability, and environmental friendliness. They are classified as inorganic (zeolite, activated carbon, clay), natural organic (corn straw, milkweed, cotton), and synthetic organic sorbents (polyurethane sponge, polypropylene fiber(. Chapter II: Experimental This chapter is concerned with the fabrication and characterization of new agar-CMC-silver (AG-CMC-Ag NP) nanocomposite by surface modification of cellulose (extracted from Egyptian macroalga Ulva fasciata) to carboxymethylcellulose (CMC) anchored on silver nanoparticles (Ag NP), followed by agar (AG; extracted from Gelidium crinale). The biomaterials (CMC, CMC-Ag NP and AG-CMC-Ag NP) were characterized based on Fourier transform infrared (FTIR), UV-vis, X-Ray powder diffraction (XRD), transmission and electron microscopy-energy dispersive X-Ray (SEM-EDX) spectroscopy and thermogravimetric (TGA) analysis. The adsorptive performance of methylene blue (MB) as well as crude and waste diesel oil from aquatic media onto AG-CMC-Ag NP was studied by Batch experiments with the multifarious parameters of pH, contact time, temperature, amount of sorbent and initial MB dye or diesel oil concentration. The studies associated with adsorption isotherms, kinetics, and thermodynamics were carried out. Also, this chapter is containing the materials and methods applied in this study Chapter III: Results In this chapter is concerned with the obtained results as follow; -Preparation of nanocomposite, AG-CMC-Ag NP -Approximate chemical composition of Ulva fasciata and Gelidium crinale -Extracted Cellulose (A), Extracted Agar (B), synthesized CMC (C), CMC- Ag NP -Approximate chemical composition (dry biomass %) of Ulva fasciata and Gelidium crinale in addition to sulfate content of agar (D) and AG-CMC-Ag NP composite (E). -Characterization of AG-CMC-Ag NP biosorbent: 1)) UV-vis spectra of CMC-Ag NP and AG-CMC-Ag NP composite. 2)) FTIR spectra of CMC, CMC-Ag NP and AG-CMC-Ag NP composite. 3)) TEM micrographs of CMC, CMC-Ag NP and AG-CMC-Ag NP composite before and after adsorption of MB dye. 4)) EDX of CMC-Ag NP and AG-CMC-Ag NP composite before and after adsorption of MB dye. 5)) XRD spectra of CMC, CMC-Ag NP and AG-CMC-Ag NP composite before and after adsorption of MB dye. 6)) TGA and DSC thermograms of AG-CMC-Ag NP composite. -Batch adsorption process for removal of MB: 1)) The adsorption capacities of the reported biomaterials (Cellulose, CMC, AG, Ag NP and AG-CMC-Ag NP) for removal of MB dye in aqueous media (2) pHzpc (a), effect of pH (b), temperature (c), contact time (d), sorbent weight (e) and MB dye (f) on adsorption of MB onto AG-CMC-Ag NP composite (3) Adsorption kinetics of MB dye onto AG-CMC-Ag NP; Pseudo first-order (a), Pseudo second-order (b) and intraparticle diffusion(c). 4)) Kinetic parameters for adsorption of MB onto AG-CMC-Ag NP Nanocomposite. 5)) Langmuir (a), Freundlich (b), Temkin (c) and Dubinin-Radushkevich. (d) isotherm models for the adsorption of MB dye onto AG-CMC-Ag NP. 6)) Isotherm parameters for adsorption of MB onto AG-CMC-Ag NP Nanocomposite. 7)) Thermodynamic parameters for adsorption of MB onto AG-CMC-Ag NP Nanocomposite. 8)) Desorption and reusability of AG-CMC-Ag np composite for the adsorption of MB dye. 9)) Adsorption of MB dye from Real and synthetic water matrix. -Interaction between MB dye and AG-CMC-Ag NP sorbent: - FTIR spectra of AG-CMC-Ag NP composite before and after adsorption of MB dye. - Waste diesel oil absorption onto AG-CMC-Ag NP composite. - Preparation of aerogel (i) and dispersion of AG-CMC-Ag NP/aerogel in crude (ii) and waste diesel oil (iii). - The chemical compositions of the applied biomaterials (cellulose, CMC, AG, Ag np and AG-CMC-Agnp; Fig. 16) have a significant effect on the adsorption of diesel oil. - Adsorption of crude diesel oil onto the reported aerogel sorbents (g g-1). - Adsorption of crude diesel and waste oil onto AG-CMC-Ag NP Composite. 1)) Effect of temperature (i), time (ii), oil concentration (iii) and sorbent dose (iv) on adsorption of diesel oil onto AG-CMC-Ag NP/aerogel. (2) Adsorption kinetics of Crude and waste diesel oil onto aerogel AG-CMC-Ag NP; Pseudo first-order (i), Pseudo second-order (ii) and intraparticle diffusion (iii).
3)) Kinetic parameters for adsorption of diesel oil onto AG-CMC-Ag NP/aerogel.