Chemistry

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POLYMER WITH A DUAL ADSORPTION SITES: DESIGN, SYNTHESIS AND PURIFICATION OF POLLUTED WTAER FROM HEAVY METALS AND TOXIC ANIONS
(0202-04-03) Raneem Ahmad Abu Aysheh
Demand for clean is increasing due to the increase in population. Recycling of contaminated wastewater could be an answer for this issue. Wastewater is contaminated with a variety of toxic materials depending on the contamination source. The pollutants mainly include metal ions and organic matters that are released from various sources such as medical, plumbing, agricultural, body care products, household chemicals, and industries. Among the toxic heavy metals that raise a serious concern are Cr²⁺, Pb²⁺, Hg²⁺, Cd²⁺, and others that are harmful to creatures. To remove hazardous heavy metals' pollutants and enhance water quality, researchers used various adsorbent that are polymer based. Modifying existing polymers could be the simplest and most effective way to generate a low-cost adsorbent with high efficiency against metals and hazardous organic compounds. Among all developed techniques, the adsorption removing approach has attracted the most attention. It has been particularly interesting to develop a superior adsorbent demonstrating a high adsorption capacity and low cost for removing various pollutants from contaminated waters. This study aims to develop cellulose with multi coordination site and zwitterionic functionality. This study was planned to generate cellulose with multi coordination site and zwitterionic functionality. These criteria make it superior adsorbent for application in purification of polluted wastewater. The target cellulose was designed to have coordination sites for toxic heavy metals and toxic anions such as nitrate. The method of making the polymer comprises three steps: the first step involves adding an aldehyde functionality to cellulose powder by oxidation (Cell-Ald). In the second step Cell-Ald was crosslinked with a polyamine such 1,4-pheneylendiamine (PPD) to produce a 3D structure with multi coordination site, which then will be reacted with 1,4-butane sultone to form the target polymer cellulose with zwitterionic functionality (Cell-3D-ZWI). The polymer structure was confirmed by FT-IR. The polymer was evaluated for their ability to adsorb Pb²⁺ ions. The percentage of metal adsorption was investigated as a function of Temperature, pH, adsorbent dosage, contact time, and initial concentration of metal ions. The high efficiency in adsorbing heavy metals from wastewater, with the maximum adsorption result for Pb²⁺ being 97.43% at pH ≈7.21, adsorbent dosage =20 mg, initial concertation of metal ion =10 ppm, contact time =20 min and temperature =20°C. In addition, the adsorption isotherm, kinetics, and thermodynamics were measured. The thermodynamic parameters of Pb²⁺ adsorption is spontaneous (ΔG°<0), exothermic process (ΔH°<0) and the reaction occurs spontaneously at low temperatures (ΔS°<0). All adsorption processes follow the pseudo- second order adsorption kinetics model (R²= 0.99), which was established by the adsorption parameters, and these adsorptions were matched with the Freundlich isotherm of adsorption (R²=0.89). The target compound was prepared and identified by IR spectroscopy, it has good thermal stability, it adsorbed metals from wastewater at high efficiency. Keywords: Cellulose, Water pollution, Wastewater treatment, Heavy metal, Lead, p-Phenylenediamine, 1,4-butane sultone, Zwitterions.
Spectrophotometric and Electroanalytical Determination of Prilocaine
(2000) Ismail Mohammed Badran; Prof. Ali Z. Abu Zuhri; Dr. Raqi Shubietah
Sensitive and selective spectrophotometric and voltammetric methods for the determination of Prilocaine have been developed. The spectrophotometric method was based on the formation of colored ion-pair complexes between Prilocaine and each of Bromothymol Blue (BTB) and Bromocresol. Green (BCG), the complexes formed have been extracted with chloroform and exhibit maximum absorbance at 416 and 420 nm for BTB and BCG, respectively. Beer’s law was obeyed over a wide range (2.0 - 24.5 ppm) for BTB, and (2.0 - 26.5) ppm using BCG, with molar absorptivities (s) equals 1.68 >< 104 L mol" cm" and 1.83 x 104 L mol" cm" using BTB and BCG respectively. RSD were found to be 0.61% and 0.53% for BTB and BCG respectively. All factors affecting the color formation, extraction, sensitivity and reproducibility of the method were studied, among which are; effect of pH, type of solvent, shaking time, amount of buffer, concentration of dye, temperature, stability of complex formed, and stoichiometry. The voltammetric method was based on direct determination of Prilocaine using differential-pulse adsorptive cathodic stripping voltammetry (DP-AdCSV) in basic medium using Britton-Robinson (BR) buffer. The factors affecting the sensitivity of the method has been investigated to optimize the determination method, among these factors are: pH, accumulation potential, accumulation time, scan rate, drop size, and pulse amplitude. Calibration graph was found to be linear over the range (0.16-21.6 ppm) (6.2 >< 10⁷-8.4 x 10⁵ M) with detection limit equals 0.16 ppm, and RSD of 0.68%. The suggested methods were compared with other existing spectrophotometric, chromatographic and electroanalytical methods. It was found that, the suggested methods were relatively sensitive, accurate, precise, and could be applied successfully for the determination of Prilocaine without any interference from the drug ingredients.
Extractional Spectrophotometric Determination of New Substituted Tricyclic Pyridopyrimidines
(2000) Ghassan Mahmoud Ismail; Prof. Ali Z. Abu Zuhri
A simple and sensitive method was developed for the extractional spectrophotometric determination of new substituted tricyclic pyridopyrimidine compounds (I) (7-chloro-2,3-trimcthylene-pyrido [1.2-a] pyrimidine-4-one), (II) (7-bromo-2,3-tetramethylene-pyrido [1,2-a] pyrimidine-4-one) and (III) (7- methyl-2,3-tetramethylene-pyrido [1,2-a] pyrimidine-4-one). The method was based on the formation of ion-pair complexes between compounds I, II and III with bromothymol blue (BTB). The absorbance of the produced ion-pair complexes were measured at 414, 418, and 418 nm for I-BTB, II-BTB and III- BTB respectively. Beer’s law was obeyed over the concentration ranges 0.04 -5.10, 0.12- 5.58 and 0.76-6.82 ug/ml for compounds I, II and III, respectively. Molar absorptivities for compounds I, II and III, were found to be 8.0 x 10ᶟ, 8.0 x 10ᶟ and 1.2 x 10⁴ L mol⁻¹ cm⁻¹, respectively. All factors affecting the sensitivity and reproducibility of the method were studied such as pH, shaking time, concentrations of BTB, amount of buffer, type of solvcnt, number of extraction times and stoichiometry. The method was applied for spectrophotometric determination for compounds I, II and III.
Kinetics, Mechanism and Analytical Application of Cyanide Abstraction From Hexacy Anoferrate [II] by Mercury [II] in The Presence of Ferenes
(2000) Imad Abdel Mun'em Mahmoud Harb; Prof. Bassem F. Shraydeh
The kinetics of cyanide abstraction from potassium hexacyanoferrate (II) by mercuric chloride in the presence of the ligand Ferene S in aqueous solutions have been investigated spectrophotometrically by measuring the change in the absorbance of the blue Ferene-ferrous complex at 593 nm. The reaction rate between potassium hexacyanoferrate (II) and Ferene is dramatically a slow process, while in presence of a trace amount of mercury (II) the reaction tends to completion within few minutes. Effect of pH, temperature, hexacyanoferrate (ll), Ferene S, and mercury(II) concentrations on the rate of the reaction have been investigated. The order ofthe reaction has been found to- be first order with respect to potassium hexacyanoferrate (ll), Ferene S, and mercury (II) chloride. Activation parameters for both the catalysed and the uncatalysed reactions have been calculated. A proposed mechanism that could explain the results has been suggested. A kinetic method for mercury determination in medicinal samples has been proposed.
Kinetics and Mechanisms of Aquation Reactions of Tris (Ferene) Iron (II) Complex : Analytical Applications in Kinetic Determinations
(2001) Daoud Mahfouz Daoud; Prof. Bassem F. Shraydeh
In the present work the tris (Ferene) iror (II) complex has been applied for kinetic determinations of N-acetylcystcine ,phenol, 1,4-phenylendiamine , 2,4-diaminotoluene and 8-aminochinolin . Kinetic determinations of NAC , phenol and these amines were undertaken using fixed time method whereby absorbance of the his (Ferene) iron(II) complex was measured after 5 minutes of addition of Fe(III). The stability of the tris (Ferene) iron(II) complex in mixed aqueous organic cosolvent was studied and the kinetics determined. The order with respect to the complex is found to be unity and zero order with respect to acid. A suitable mechanism was postulated for the aquation of the above complex. The activation parameters were also determined.
Synthesis of A New Series of Heterocyclic Scaffolds for Medicinal Purposes
(2001) Randa Yaser Arafat; Dr. Taleb H. Al-Tel; Prof. Hikmat S. Hilal
A new series of substituted 8-fluoro-4H-pyrimido[2, l-b][l,3] benzo- thiazole-4-ones (24) and (25), substituted 7-methyl-4H-isoxazolo[2, 3-a] pyrimidin-4-ones (26-28), and substituted 2-methyl-5,6,7,8-tetrahydro-9H- isoxazolo[2, 3-a] pyridopyrimidin-9-ones (29) and (30), have been prepared via condensation of β- keto esters with 2-aminopyridine derivatives. Furthermore diazipine Compounds (31-33) have been prepared via condensation of a γ-keto ester with 2-aminopyridine derivatives. The reactions were conducted in the presence of poly phosphoric acid (PPA). The details of the synthesis procedures are described. The new compounds have been characterized using elemental analysis, GC MS, FT IR and NMR spectrometry. Compounds 24, 27 and 28 were tested against Staphylococcus aureus, proteus vulgaris, and candida albicans bacteria. None of the three compounds showed antibacterial activity. The same compounds were tested against Microsporum canis, jusiarium tricincutum, pythium ultimum, pythium aphanidermatum, and pythium midlletonii fungi types. All of them showed antifungal activity. Compounds 27, 32 and 33 were tested for anticancer activity by the MTT assay. They all showed significant anticancer activity.
Surface Modification of N-Gaas Semiconductor With Metalloporphyrin / Polysiloxane Matrices Effect of Modification On : Band-Edge Positions, Short Circuit Current and Surface Stability in Aqueous Photoelectrochemistry
(2001) Muayad Masoud Mahmoud Masoud; Prof. Hikmat S. Hilal; Dr. Samar Al-Shakshir
Semiconductor (SC) surfaces are currently being investigated as catalysts for solar energy utilization. In one of the most important applications of photoelectrochemical (PEC) cells, SCS are used as photocatslysts for water splitting. Unfortunately, there is no available SC that satisfies all the features of a good SC catalyst for PEC water splitting. Therefore, it is desired that the band edges of SC be shifted, mainly positively, to improve the charge transfer processes at the surface and to enhance the SC surface resistance against deterioration. We have developed a new technique to tailor the positions of SC band edges. Tetra (-4-pyridyl)porphyrinatomanganese(III)sulfate (MnP), existing in the form of Mnm and Mnu ion mixture, was embedded into a polysiloxane polymer matrix and was attached to the surfaces of n-GaAs wafers. The n- GaAs/polymer/MnP system was annealed under nitrogen and used for photoelectrochemical study in water/LiClO4 and Fe(CN)63'/Fe(CN)64` as a redox couple. The results indicated a positive shift in the value of the flat—band potential of the SC due to the presence of the MnP. Mott-Schotky plots indicated positive shift in the value of the flat-band potential. This was also manifested by shifting the values of the dark-current onset potential and the photocurrent open-circuit potential towards more positive values. Unlike earlier reports, the values of the short-circuit currents, measured with time of exposure, were significantly enhanced by modification. The modified surfaces were more stable, to photodegradation, than the unmodified surfaces while using high intensity illumination. The n-GaAs/polymer/MnP electrode showed higher cell efficiency than the unmodified.
Voltammetric and HPLC Determination of Some Textile Dyes
(2003) Amani L.N. Zu'bi; Prof. Ali Z. Abu Zuhri; Dr.Nidal Za'tar
Simple and sensitive voltammetric and HPLC methods were developed for the determination of the three azo dyes (Acid Orange 7, Acid Orange 10 and Acid Orange 12). Optimization of various experimental conditions for quantitative determination of dyes is described. The voltammetric method for determination of trace amounts of dyes is carried out by differential pulse-adsorptive cathodic stripping voltammetry (DP-AdCSV) technique at a hanging mercury drop electrode (HMDE). The effects of different parameters that influence the (DP-AdCSV) response are described. These parameters include pH, accumulation potential, accumulation time, pulse amplitude, scan rate, drop size and interference by other ions. The calibration graphs for the determination of the studied dyes were linear in the range 0.004-0.105 ppm, 0.009-0.180 ppm and 0.007-0.140 ppm with detection limit of 0.002 ppm, 0.005 ppm and 0.004 ppm and relative standard deviation of 1.96%, 2.10% and 2.15% for Acid Orange 7, Acid Orange 10 and Acid Orange 12 respectively. The HPLC method for the determination of dyes using optimum conditions is carried out. The wavelengths of maximum absorbance were 477nm for Acid Orange 10, 485nm for Acid Orange 7 and Acid Orange 12. Retention times were found to be 2.8 min, 4.8 min, and 3.1min for Acid Orange 7, Acid Orange 10 and Acid Orange 12 respectively. Calibration graphs for the determination of the studied dyes were linear in the range 0.05-4.0 ppm, 0.10-4.0 ppm and 0.10-4.0 ppm with relative standard deviation of 3.8%, 4.1% and 4.2% and detection limit of 0.03, 0.05 and 0.05 ppm for Acid Orange 7, Acid Orange 10 and Acid Orange 12 respectively. The Reducing degradation kinetics of the studied dyes by zero-valent iron in aqueous-solutions were studied. Effective degradation was achieved with rate constants of 0.004, 0.002 and 0.003 mmol/L.min, and half-lives of 10 min 22 min and 17min for Acid Orange 7, Acid Orange 10 and Acid Orange 12 respectively.
I-Determination of Lead and Cadmium in Food by Anodic- Stripping Voltammetry II- Oxidation of Galactose
(2004) Shadi Abdel-Qader Suleman Mousa; Prof. Dr. Mohammed Al-Subu; Prof.Dr. Radi Dauod
In part (І) trace metal concentrations in food, cigarettes and water was determined. Reprehensive samples were taken during May- August 2003.Food samples were digested and then analyzed for their contents of lead and cadmium. Samples were analyzed using anodic stripping voltammetry, which considered being sensitive compared to other methods used in determination of heavy metals. The results showed very low concentrations that were below the safe limits of lead and cadmium set by the WHO. In part (ІІ) reaction of galactose with potassium hexacyanoferrate (ΙΙΙ) in alkaline medium was studied at constant temperature and ionic strength.Stoichiometric studies showed that for each mole of galactose oxidized, two mole of potassium hexacyanoferrate (ΙΙΙ) were reduced to produce galactonic acid. The dependence of rate on the concentration of each of galactose, heacyanoferrate (ΙΙΙ) and hydroxide ion was determined. The reaction followed first order rate dependence on both; galactose and hydroxide ion and the rate was independent of
Kinetic Studies of the Hydrolysis of Furfurylidenefuroyl Hydrazone Derivatives, Solvatochromism and Fluorimetric Determination of Iron (III)
(2005) Mahmoud Mohammed Issa Gabaga; Prof. Bassem Shraydeh
Preferential solvation of di-2-pyridylketonebenzoyl hydrazone was investigated in aqueous-ethanol binary mixtures. The kinetics and mechanism of the hydrolysis of a series of substituted furfurylidenefuroyl hydrazones (X-FFH)  in  25% (v/v) ethanol-buffer mixtures have been studied by ultraviolet visible spectrophotometry at different temperatures in the range 22-500C. The hydrolysis reactions were found to follow first-order kinetics. The effect of pH, molecular structure and temperature on the rate of hydrolysis have been discussed. A mechanism for the hydrolysis is postulated in which the attack of water on the protonated substrate is subject to general acid-base catalysis using HCl-sodium acetate buffer solution. The hydrolysis of 5-Chlorothiophenylidene salicoyl hydrazone (CTSH) was found to obey specific acid catalysis using HCl-KCl buffer solutions. The observed rate constants and the catalytic rate constants with respect to H+, HC2O4- and H2C2O4 were calculated. Activation energy and thermodynamic parametres for the hydrolysis are evaluated and discussed. A sensitive method for the determination of iron (III) in trace levels using fluorescence spectroscopy was devised. The method is based on the oxidation of di-2-pyridylketonebenzoyl hydrazone by hydrogen peroxide whereby Fe (III) shows an inhibition effect on the emission signal. The detection limit of Fe (III) was found to be 3.0x10-6M. Interference studies and order of addition were also investigated.  The method was successfully applied to milk and other medicinal samples.
HPLC Determination of Four Textile Dyes and Studying their Degradation Using Spectrophotometric Technique
(2005) Safwat Mohammad Abdul Azeez Saleh; Dr. Nidal A. Za'tar; Prof. Maher A. Abu-Eid
In the present work, a simple and a sensitive HPLC method was developed for quantitative determination of four Direct textile dyes (Direct Red 81, Direct Blue 15, Direct Black 22 and Direct Orange 34). The maximum absorbance value for the above mentioned dyes were found to be at 510 nm, 607 nm, 484 nm and 411 nm, with retention times of 15.4, 8.8, 5.8 and 12.7 min, respectively. The mobile phase used was consisting of acetonitrile: water (60:40, v/v) containing 0.45 M N-cetyl-N,N,N-trimehyl ammonium bromide (CTAB). RP C18 column was used with a flow rate of 0.5ml/min. Calibration graphs were found to be linear over the ranges of 0.3–10ppm, 10–30ppm, 0.5–10ppm and 1–12ppm for Direct Red 81, Direct Blue 15, Direct Black 22 and Direct Orange 34, respectively, with limit of detection 0.3ppm, 10ppm, 0.5ppm and 1ppm. The relative standard deviations (RSD%) were found to be 0.92 %, 0.83 %, 1.13 % and 0.34 %, respectively (n=3) with concentrations of 10ppm of each dye. The effect of pH, CTAB concentration and acetonitrile: water ratios (v/v) in the mobile phase on the determination of the four Direct azo dyes were investigated. The reducing degradation kinetics of the four Direct dyes; Direct Red 81, Direct Blue 15, Direct Black 22 and Direct Orange 34 by zero– valent iron and aluminum metals in aqueous solutions were studied. Effective degradation was achieved when using Al compared to Fe. The results show that the rate of degradation is affected by acidity, amount of iron and aluminum, temperature and speed of solution agitation. The effect of metals nature on degradation of the four Direct azo dyes was studied. The following metals were used in this study (Mn, Ni, Co, Zn, Mg and Cu). The obtained results showed that using Cu do not effects on degradation rate, where using Al, Mg give a higher degradation rate compared to iron.
Determination of Some Fluoroquinolone Antibacterials with DNA-Modified Electrodes and their Oxidation by Potassium Hexacyanoferrate(III)
(2006) Ibrahim Diab Najeeb Abu-Shqair; Prof. Radi Daoud; Prof. Mohammad Al-Subu
UV-visible spectroscopic and electrochemical methods were used to study the interaction of some fluoroquinolones with calf-thymus DNA. UV-visible spectroscopy was used to evaluate the binding constants of drug-DNA complexes and to elucidate the nature of binding of of these drugs with DNA. The interaction of the studied fluoroquinolones with DNA was investigated by cyclic voltammetry at a glassy carbon electrode with an irreversible electrochemical equation. The diffusion coefficients of both free and bound fluoroquinolones (Df, Db), the binding constant (K), and the binding site size (s) of fluoroquinolone-DNA complexes were obtained simultaneously by non-linear fit analysis of the experimental data. The results suggested that fluoroquinolones bind to DNA through an electrostatic mode of interaction with partial intercalation. DNA-modified glassy carbon electrodes were used for the first time as a biosensor for the determination of the studied compounds. Differential-pulse anodic stripping voltammetry was used for investigating different factors that affect the oxidation of the studied fluoroquinolones at the DNA-biosensor. A method was proposed for the determination of ciprofloxacin concentration both in tablets and in a biological fluid (urine). The method was found to be sensitive, accurate, and inexpensive. Kinetics of osmium tetroxide catalyzed-oxidation of the studied fluoroquinolones by potassium hexacyanoferrate (III) in alkaline medium were studied. The rate was found to be independent on the concentration of hexacyanoferrate (III), and first order with respect to both fluroquinolone and OsO4. An empirical rate law was derived for the reaction, and the effect of various variables on the rate of reaction was studied. Thermodynamic parameters (Ea, ΔH*, ΔS*, ΔG*) were also calculated.
Methods of Extracting Cellulosic Material from Olive Pulp
(2009) Yusra Foad Abedel Hafith Salameh; Dr.Othman Hamid
Jefft is an important solid waste generated in large quantities every year from olive oil extraction process.Jefft is considered a lignocellulosic material, so it consists of components similar to that of wood such as cellulose, lignin, and hemicellulose. Jefft is produced from  natural product, so it is considered a renewable source of cellulose. In this study about 30% of pure cellulose was extracted from Jefft.The separation of cellulose from Jefft was performed in four stage : extraction, pre-hydrolysis, pulping, and bleaching. Our study showed that two steps of pulping and bleaching could be as good as the four steps one.In the extraction step, the extractable materials such as residual olive oil were removed.In the second step the Jefft was subjected to treatment with diluted solution of sulfuric acid (5%) or sodium hydroxide (5%) under a pressure of about 5 psi. This step was useful in opening the Jefft structure and make it more accessible to pulping and bleaching chemicals.Then Jefft was subjected to pulping by either acid or Kraft pulping process.Results indicate that Kraft pulping is considered to be more suitable to used in this study, since with the Kraft process higher yield of cellulose was obtained, in addition chemicals used in this study was recyclable.Recycling of chemicals is a very important factor in this study, since we are planning in scaling up the process to a multi-ton process.In the Kraft process, Jefft was treated with a solution of sodium hydroxide and sodium sulfide under a pressure (5 psi).Resulting cellulose was then subjected to treatment with various oxidizing agents in a process called bleaching process. Various sequences of oxidizing agents each consisting of at least four oxidizing agents were studied. The best results were achieved when using the sequence of CEHP which consists of the four oxidizing agents: chlorine, sodium hydroxide, hypochlorite, and hydrogen peroxide. Cellulose produced, using this sequence, showed the lowest contents of lignin as was determined by Kappa No. procedure. Viscosity was determined to cellulose produced from CEHP bleaching sequence, from the viscosity, the DP was determined to be about 315. These results indicate that, cellulose extracted from Jefft has a structure that could be similar to that of microcrystalline cellulose (MCC).Results summarized in this thesis indicate that we have succeeded in converting waste solid Jefft into valued added product MCC.MCC is a valuable natural polymer that is very useful in unlimited numbers of commercial applications such as food, medicine, construction, absorbents, and many others.
Curcumin Based Diazoles and Oxazoles with Potential Antibacterial Activities
(2009) Nuha Abdel-Rahman Mehdawi; Dr. Othman Hamed; Dr. Ayman Hussein
A new series of curcumin based heterocyclic compounds pyrazoles, isoxazoles and others have been prepared via reactions of curcumin with hydrazine derivatives. The reactions were conducted in the presence of acetic acid as catalyst and solvent. In addition to these heterocyles, curcumin based β-iminoalcohol (7) was also prepared. the details of the synthetic procedures are described in the experimental part. The prepared heterocyclic compounds have been characterized by various spectroscopic techniques such as , FT-IR, 13C and 1H NMR spectroscopy.Some of the compounds were analyzed by elemental analysis and others by LC/MS. The curcumin based heterocyclic compounds were then evaluated for potential antibacterial activities against four different types of bacteria: Staphylococcus aureus, Escherichia coli, Proteus mirabilis and Pseudomonas aeruginosa. Bioactivities against Proteus mirabilis and Pseudomonas aeruginosa, were negative with all compounds.However some of them showed some activities against Escherichia coli.All compounds were active against S. aureus, mainly in the case of 4-((1E,1’E)-(3,6-dihydro-2H-1,4-diazepine-5,7- diyl)bis(ethene-2,1-diyl))bis(2-methoxyphenol), compound no. 4, was the best.
Adsorption and Desorption Characteristics of Endosulfan Pesticide in Three Soils in Palestine
(2009) Karbola' Mohammed Aref Jaradat; Dr.Shehdeh Jodeh; Dr.Nidal Za'tar
In this thesis adsorption and desorption features were studied in details in three samples from the soil of Palestine. Soil samples were red soil, chalk soil, and sandy soil according to American Society for Testing and Materials (ASTM) scale for the classification of the soil. Adsorption and desorption rates on soil samples were calculated from kinetic studies. The values varied based on the type of soil. Maximum specific adsorption capacities (qmax) for soil samples using Langmuir model, were as follows: 0,387 (red soil), and 0,281(chalk soil), and (0.075) sandy soil mg / g of endosulfan. Maximum adsorption was measured in red soil followed by chalk soil, but it was the least for the sandy soil. Also, the proportion of organic matter play a major role in both processes adsorption and desorptio on soil samples. here was a significant reduction in the process of Adsorption in soil samples compared with the decline in pH. Desorption was higher at both acidic and alkaline pH ranges compared to neutral pH. Both the increase in temperature and concentration increase the adsorption and desorption in all soil samples. Finally, the results showed that the mobility of endosulfan, is more possible in the sandy soil followed by red, followed by chalk soil This may be attributed to the crystal lattice of red soil that play an important role in both processes adsorption and desorption, as it could be a major role for chemical and biological processes that play a role in the other soil samples.
Recyclable Pd (II) Catalysis on Polymer and Natural Products Supports
(2009) Hisham Awad Abed Shehadeh; Dr.Othman Hamed; Dr. Waheed Jondi
Three palladium-complexed compounds were prepared and applied successfully in catalyzing many reactions such as Heck and Wacker reactions and also used in carbonylation of olefin. Polymeric polyimine palladium catalyst 12 was prepared from palladium metal immobilized on a polyimine polymer11. This polymer was prepared by condensation of a dialdehyde (1,4benzenedicarboxaldehyde 10) and diamine (ethylene-diamin). Then Palladium metal was introduced on the polymer to give the catalyst. The prepared polymer catalyst was used in synthesis of 2-hydroxy cycloketones and 2-methoxycycloketones as follows: 2-hydroxy cyclohexanone 15 from cyclohexanone, 2-methoxycyclohexanone 31 from cyclohexanone, and α-hydroxy acetophenone 16 from acetophenone. The products were characterized spectroscopicaly using GC, NMR, IR as well as elemental analysis. The used complex catalyst was reused in the second and third catalytic cycle after washing it with toluene. The reactivity of the catalyst was not diminished in the second and third cycle. However we failed to estimate the percent of Pd remained in the complex after the third usage. In the second part of this work we prepared two complexes from the cheap starting material Curcumin 6. Curcumin, a natural product, along with two other curcuminoids 7 and 8 were extracted from turmeric. The mixture obtained was 3.57g (11.3% yield). The majority of this yield (88%curcumin ) was reduced in the presence of Pd/H2, to THC 24 which then reacted with 2 equivalents of benzylamine to give THCDBI 25 and then palladium was introduced on it. Pd+2 was prepared from oxidation of palladium sponge Pd0 in the presence of acetonitrile, nitrosonium tetrafluoroborate salt and freshly distilled acetonitrile. The reacture mixture was carried out with stirring under N2 to give a yellow golden solid. The yellow solid was filtered, washed with hexane, and dried under vacuum. The produced complex Pd (II)-THCDBI 26, was used to convert cyclopentanone to α-hydroxycyclopentanone 30,cyclohexanone to 2-hydroxycyclohexanone 15, 2-methylcyclohexanone to 2-hydroxy-6-methylcyclohexanone 33 and Propiophenone to 2-hydroxypropiophemone 35. All of the prepared products were characterized spectroscopically using GC, NMR, IR as well as elemental analysis. In the third part, we prepared the last complex which is THCDI-Pd complex 28. THC 24 was reacted with excess ammonia gas to produce light brown solid in 87% yield which turned out to be Tetrahydrocurcuminoids imine (THCDI) 27. Compound 27 was analyzed by 1H and 13C NMR. In the last step of the synthesis, palladium ion Pd+2 was introduced into the curcumin-imine compound (THCDI) to form the complex THCDI-Pd 28. The IR spectral data indicate the presence of Pd in the new complex since the band for C=N dropped by 35 cm-1. This drop is due to the formation of Pd-N bond and as a result of back bonding from 4d orbitals of the metal to the empty *π of the C=N bond, and so the bond order of C=N decreased causing the IR frequency to shift down. The prepared complex Pd (II)- THCDI 28 was used in the synthesis of 2-hydroxycyclohexanone 15, 2-hydroxy,6-methyl-cyclohexanone 33, and 2-hydroxypropiophemone 35. All of the spectroscopic analysis were in agreement with the results; however, we failed to calculate exactly the amount of Pd metal left in the residue for the polymeric complex. On the other hand we prepared and applied successfully the polymeric complex and hence a recyclable and environmentally friendly complex became possible.
Production of Bio-Ethanol from Olive Pulp
(2009) Amal Omar Husni Shalabi; Dr. Othman Hamed; Dr. Shehdeh Jodeh
Jeft is a side product of oil industry.It consists of wood components: cellulose, hemicelluloses, lignin, and extracts.We succeeded in extracting about 40-45% cellulose from Jeft.The extracted cellulose was subjected to analysis by IR, Sugar contents, Intrinsic Viscosity, and Scanning Electronic Microscope.Results of these analyses indicate that cellulose present in Jeft has a microcrystalline structure with low IV (Intrinsic Viscosity).This property makes it ideal for drug and food applications. In this study, Jeft and extracted cellulose were subjected to hydrolysis to sugar by acids such as HCl and H2SO4.The purpose of the hydrolysis was to convert produced sugar to ethanol which could be used as auto fuel.Highest yield of 64% sugar was obtained using acid alone (concentrated HCl).The yield of sugar was enhanced to about 49.89% using diluted HCl (10%) with Lewis acid ZnCl2(20%) . These results indicate that cellulose obtained from Jeft has a microcrystalline structure.These results are consistent with the results obtained fromIntrinsic Viscosity (IV), Scanning Electron Microscope (SEM), and Infrared spectroscopy (IR) studies which all showed that cellulose has a microcrystalline structure.Medium rate of hydrolysis could be attributed to the high crystallinity of cellulose which reduces the accessibility of hydrolyzing agent to cellulose structure.
Kinetics Of Groundwater Nitrate (NO3 -1) In Soil Leachate In Tulkarem City Using Soil Columns
(2009) Osama Zaki Mohammed Naser; Dr. Shehdeh Jodeh; Prof. Marwan Haddad
As we know nitrate ions are considered to be global pollutant that pollute water sources which include surface and ground water. This pollution results mainly from nitrogen fertilizers in agricultural areas, wastewaters and animals manure. World Health Organization (WHO) standards of the nitrate ions concentration is put at 45 mg/l, hence any source of water exceeding this value consider as contaminant and put in focus for treatment. The method of vertical columns that are filled with different types of soil taken from TulkaremCity is to study the effects of soil on the groundwater if contaminated water with nitrate leaches through the soil and its relationship with elevation of nitrate in these areas.Three soil samples of different concentrations of nitrate will be collected from near TulkarmMunicipality wells no (1, 3 and 5). These samples will be put in nine vertical plastic tubes (PVC), then these tubes will be divided into three parts designated as zero-short-long-term of concentrations (0 year, 1 years, 25 years) for each soil sample. Three different concentrations of nitrate-contaminated water will be added as time-term of concentrations to nine columns daily. For the columns, blank and short-term of time concentration (1 year), the high concentrations of nitrate ions concentrated in the bottom of the columns while the lower concentration concentrated in the upper of the column. For the columns long-term of time of concentration (25 year) high concentrations of nitrate ions concentrated in the upper of the columns while the lower concentration concentrated in the bottom of the columns. The results indicate that the texture of the soil is sandy to sandy loam and contain high percentage of organic matter ranging from 3.71 % to 4.25 %. It is found that the average concentration of nitrate ions in the content of the soil samples (1, 3 and 5) is equal to 263.3 mg/L, 216.7 mg/L and 799 mg/L respectively. Kinetic studies (Freundlich adsorption isotherm) is applied to study the adsorption of nitrate ions to the soil particles in the wells no. (1, 3 and 5). The results of adsorption study of wells 1, 3, and 5 are found to be 0.611, 0.779 and 0.821 respectively. These results are satisfactory where the optimum time for adsorption of nitrate ions was after 24 hours.
Sorption Characteristics of Nonionic Surfactant Triton X-100 in Soil Contaminated with Diesel
(2009) Mahmoud Ali Mohammed Al Haitali; Dr.Shehdeh Jodeh
Surfactant with its amphiphilic nature toward polar and nonpolar substances may be used in mass transfer improvement of hydrophobic pollutants from solid or non-aqueous liquid phase into aqueous phase by decreasing interfacial tension and formation of micelles which surround these pollutants and solubilize them into aqueous phase. Micelles are often characterized according to their size and shape. The geometric properties of these micelles depend on the chemical structure of the surfactant and on the concentration and the nature of the aqueous environment. The adsorption of the surfactant on solid surfaces can lower the concentration of free surfactant in aqueous solution. If the degree of adsorption is high, surfactant concentration could drop below the Critical Micelle Concentration (CMC), rendering the surfactant solution with no ability to solubilize. Therefore, the amount of surfactant mass that will sorb should be accounted for when selecting injection concentration. In this study, diesel was used as an organic contaminant to study sorption characteristics of non ionic surfactant, Triton X-100 onto soil below and above CMC. The surface tension measurement was used for calculating this kind of sorption. Nonionic surfactant Triton X-100 was used to study remediation enhancement of diesel contaminated soil. UV-Visible Spectrophotometer was used to determine the amount of diesel removed from contaminated soil by surfactant via solubilization and mobilization mechanisms at 254 nm.The results indicated that when the concentration of surfactant was lower than the CMC, the amount of surfactant sorbed on soil increased with increasing the surfactant concentration; the amount of desorbed diesel was relatively low compared with the original amount added to soil, but amount of diesel desorbed from soil at surfactant concentration above CMC was relatively high. Other factors such as temperature, pH, and ionic strength were also studied to examine whether they improve or inhibit diesel desorption from soil. The study has shown that high pH, low pH, high temperature, and ionic strength decreases the capacity of surfactant in desorption of diesel from soil.
Fate of Oxytetracycline and Doxycycline in Soil and Underground Water
(2010) Lama Smeeh Mohammad Awartani; Dr. Shehdeh Jodeh
Pharmaceutical pollution is one of the most serious types of environmental pollution, that attracts increasing attention & lead research studies in recent years. Because of their great impact on aquatic life, soil & under ground water as emerging aquatic micro pollutants that have possibly been affecting the ecological system. It could have major implications on plants, wildlife and humans who may be directly & indirectly be responsible of this type of pollution. In this study two antibacterials were selected, oxytetracycline & doxycycline as examples of pharmaceuticals that are released into the environment, both are marketed in the Palestinian market either for human pharmaceutical industry or the veterinary one. In this research the adsorption behavior of both pharmaceuticals on soil, the effect of organic matter, the effect of magnesium chloride hepta hydrate addition on polluted soil, in addition their effect on characteristics of under ground water, all were studied using the UV-Vis spectrophotometry. The results showed that increasing organic matter increases the adsorption of oxytetracycline more than doxycycline, also showed that the composition of oxytetracycline complex with magnesium ion was more stable than doxycycline complex with magnesium. The study also revealed a higher concentration of doxycycline in leachate water from the soil than those of oxytetracycline, because doxycycline has higher solubility in water. It also showed a decrease of the concentrations for both substances over time in leachate water due to degradation. The degradation of both pharmaceuticals in soil & water would be produced by other substances may be harmful, as the threat of their presence in the soil and groundwater would increase the resistance of bacteria in the soil, in another words that would affect the natural properties of soil and groundwater as well.

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