Chemistry
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- ItemCELLULOSE BASED FOAM WITH IONIC FUNCTIONALITY: SYNTHESIS AND APPLICATION IN WASTEWATER PURIFICATION FROM TOXIC METALS(جامعة النجاح الوطنية, 2022-08-28) AbuAlrob, HaneenAbstract Background: The excessive applications of chemicals increased the load of contaminants in water. Organic, heavy metals ion, and inorganic contaminants pose a serious risk to creatures' life. heavy metal ions are one of the most harmful common contaminants. Scientists devoted their effort to finding an efficient, economic, commercially available, and environmentally friendly way to remove contaminants from water. Objectives: In this study, we benefit from Polyurethane foam (PUF) characteristics. PUF is easy to prepare and use in water purification. Elastic porous structure, controllable pore structure, adjustable shape, simple preparation process, high stability, and high adsorption/desorption rate. These properties make it very suitable for use as an adsorbent material for toxic metal ions. The lack of metal-binding groups in PUF limited its use in wastewater purification. PUF modified with an ionic functional group that is covalently attached to it will be synthesized and used as a metal adsorbent. Methodology: PUF preparation was carried out by polymerizing the diisocyanate compound with oxidized cellulose. The first step involved reacting cellulose with sodium periodate to produce dialdehyde cellulose. Produced dialdehyde cellulose was reacted with para-aminobenzoic acid to form a Schiff base. Schiff base was reduced by sodium borohydride to form cellulose amino benzoic acid. At the last step, a diisocyanate compound was added to form a foam with a 3D structure with carboxyl functionality. The presence of the carboxylate and amino benzoic acid groups in addition to the other PUF properties mentioned above makes the target foam novel for wastewater purification. The prepared polymers were characterized by using TGA, and FT-IR. The produced foam was used in extracting metal ions form wastewater. Optimum adsorption conditions for wastewater purification process using the prepared cellulose PUF polymers was detected. The adsorption conditions that lead to the highest efficacy were determined by running the extraction at various parameters such as: pH, contact time, temperature ℃, dosage, and initial metal ion concentration. Results: The effect of each parameter was evaluated by varying the parameter values while keeping others constant. The targeted parameters that lead to the highest efficacy were determined to be pH 7.0 and 9.0, contact time 30 and 25 min, temperature 15 and 20, dosage 250 mg, and initial metal ion concentration 15.0 and 20.0 ppm for PPUF and HMPUF respectively. An atomic absorption spectroscopy instrument was used to determine the concentration of lead after applying the polymer under certain conditions. After detecting the ideal parameters, the prepared polymers were applied to a real-life sample of wastewater. Under the optimum conditions, the efficiency of the polymers in lead removal was tested. Inductively Coupled Plasma Mass Spectrometer ICP-MS was used to determine the concentration of contaminants in the real-life sample (sewage water) after and before applying the polymer. the Langmuir model was fitted to the equilibrium adsorption data. Van't Hoff plot was used to determine ΔH°(KJ/mol), ΔS° (J/mol.K), and ΔG°( KJ/mol) values they were -7.693, and -31.44, and 9.53, -28.725, -107.2 and 32.44 for PPUF & HMPUF- NCC respectively. The results indicate that the adsorption process is spontaneous at room temperature. Kinetic study showed that the process obeys pseudo second-order the R2 value for the two polymers are very close to1. Conclusion: After detecting the optimum conditions polymers were applied to a real sample and the two polymers show excellent efficiency in the removal of heavy metals. Keywords: heavy metals, water pollution, cellulose, polyurethane foam, adsorption.
- ItemSynthesize and Characterization of Cellulose Derivataized with an Aromatic Amine and Application in Waste Water Purification(An-Najah National University, 2019-07-14) Abu Leil, BahiaA cellulose derivative with several coordination sites for metal ions composed of cellulose powder extracted from olive industry waste and 1,2-pheneylnediamine was synthesized and evaluated as an adsorbent for metal ions from sewage. The adsorption efficiency of the cellulose amine polymer toward Fe(III) and Cd (II) was investigated as a function of adsorbent dose, concentration temperature, pH, and time .The adsorption parameters that gives the highest adsorption efficiency were determined. In addition, the cellulose amine polymer showed an excellent efficiency toward approximately twenty metal ions present in the sewage sample. The highest adsorption efficiency was at pH of about 8.3, room temperature and with 2mg/ml of polymer dose. The cellulose amine polymer has various coordination sites amine, hydroxyl, and aromatic groups. The diversity and frequency of the coordination was the reason for the high efficiency of the cellulose amine polymer toward the metal ions. The thermodynamic analysis results (The Gibbs energy (ΔG0), enthalpy (ΔH0), and entropy (ΔS0) were calculated) supported the spontaneous adsorption efficiency of the polymer at room temperature. The kinetic study revealed that the metal ion adsorption by cellulose amine polymer was pseudo-second-order and followed the Langmuir isotherm model.
- ItemCellulose Functionalized with Amine Bidentate Ligand: Synthesis and Use as A Polymeric Support for Palladium Catalysts(An Najah National University, 2021-02-09) Nazem Ghaleb Ali, OraibTwo novel polymeric palladium supported catalysts were prepared and evaluated in the oxidation of alkene and ketone. The obtained results showed that, the catalysts could be used in a lab scale or commercial scale to produce α-hydroxy ketones form ketones and ketones form terminal alkenes. The polymeric material was prepared by condensation reaction of an oxidized cellulose (cellulose di-aldehyde) and 2-(2-pyridyl)ethylamine to produce cell-imine-pyridyl. Oxidized cellulose was prepared by oxidation of cellulose using sodium periodate. The polymer was characterized by FT-IR spectroscopy. The polymers then reacted with a solution of Li2PdCl4 in acetonitrile to prepare the target polymeric palladium supported catalyst (cell-pyridyl-Pd(II)). A second polymeric palladium supported (cell-picolyl-Pd(II)) catalyst was prepared in the same manner except that 2-picolylamine was used in the place of 2-(2-pyridyl)ethylamine. Hydroxylation of ketone catalyzed with cell-pyridyl-Pd(II) and cell-picolyl-Pd(II) produced α-hydroxy ketone in moderate to excellent yield, while the oxidation of terminal alkene produced methyl ketone in moderate yield. So, both polymeric supported catalysts showed good to excellent efficiency. To enhance the solubility of the reactant, a polar aprotic solvent was chosen for the oxidation reactions in the presence of CuCl2 as a Pd(0) re-oxidant and in the presence of an acid to enhance the tautomerization of ketone to enol since the oxidation occurs on enol functional group, and the tautomerization of enol back to ketone which occurs during the oxidation of alkenes. The oxidation reactions were performed at room temperature.
- ItemZeolite/Cellulose Acetate (ZCA) in Blend Fiber for Removal of Erythromycin from Aqueous Solution Experimental and Theoretical Study(جامعة النجاح الوطنية, 2021-08-24) Erman, IsraaThe highly use of pharmaceutical products in various areas has led to the worldwide pollution in the environment. However, effective purification of water contaminated by erythromycin antibiotics remains a great challenge. The more since, wastewater treatment plants are not capable of removing effectively the antibiotics. The aim of this study is to improve the performance of zeolite-A as an adsorbent material using cellulose acetate (CA) addition as a support membrane, for erythromycin antibiotics adsorption. The membrane is called as Cellulose Acetate/Zeolite-A (CA/ZA) membrane. The number of interchangeable sites in the adsorbent structures and the ratio of erythromycin to the three adsorbents were identified as the main reasons for the reduction in adsorption as the initial ERY concentrations increased. Additionally, to pseudo-first-order modelling for all adsorbents, the pseudo second-order modeling showed better fitting for the adsorption. However, the findings obtained in pseudo-first-order model were still enough for explaining the sorption kinetics of ERY, showing that the surface displayed all chemi-sorption and physi-sorption adsorption processes by both adsorbents. Also, the Langmuir and Freundlich isotherm model were discussed to find that this adsorption isotherm was fitted better by Langmuir. The three adsorbents showed negative values of ΔH and these values were -6200, -8500 and -9600 KJ/mol for zeolite, CA and ZCA respectively and this shows that the adsorption is exothermic. In addition, the chemical attitude and possible donor-acceptor interactions of the ERY were assesed by the quantum chemical parameters (QCPs) and NBO analysis performed, at the HF/6-311G** calculations.The desorption analysis shows no substantial loss of adsorption site after three runs, indicating the higher stability and resilience of the three adsorbents, indicating a strong repeatability of their possible use in adsorption processes without contaminating the environment.
- ItemPHOTOCATALYTIC DEGRADATION OF ORGANIC CONTAMINANTS BY CLAY- SUPPORTED NITROGEN-DOPED TIO2 NANOPARTICLES(An Najah National University, 2022-02-07) Jihad Mohammed Kharouf, MohammedResponding to the strong demands on new optimum photocatalyst, to decompose organic pollutants from the contaminated waste water. Titania is very effective as a photocatalyst. To achieve maximum absorption of sun light, doping was used to lowering the band gap energy. supporting on the clay successfully enhance the catalytic properties in addition to minimizing the effort of catalyst recovery. The photocatalytic activity of variety of catalysts has been studied utilizing with varying synthesis circumstances (annealing temperature, cover gas, etc.) and compositions (rutile, anatase) supported and unsupported on the clay surface. Two doping methods were made for comparison. The X-ray diffraction methods and scanning electron microscope and another elemental analysis were used to identify the catalyst states. There are no inter-layer intercalation titanium dioxide inside the clay, according to solid state studies. Another thing to note is that when the annealing temperature rises, the anatase begins to change to rutile form. Solid catalysts were used in order to photo-depredate the phenazopyridine contaminated water. Rutile and anatase titanium dioxide (naked and clay supported) types were invested as photocatalysts. Nitrogen doping using urea as a source of nitrogen effectively lowers the band gap energy, which inhibits the photocatalytic activity. On rutile, doping increases the catalytic properties and has no observed effect on band gap energy. The TiO2 (Rutile)/Clay supported catalyst outperforms the other catalysts and was successful in phenazopyridine photodegradation under simulated solar light. In addition, the ideal conditions were stated (pH, Temperature, quantities effect). Studying catalyst recovery where made for TiO2(Rutile)/Clay after four times, the efficiency of the recovered solid catalyst has not any noticeable loss. The full degradation was confirmed using TOC and HPLC which can be achieved under simulated sun light after 3 hours under the reaction conditions. As a result, supporting titania on the clay surface enhances the catalytic properties, recovery of the catalyst by simple decantation. And the doping affect differently according to the catalyst type and doping method.