An-Najah Staff

Different pollutants from industries leach every day to soil and ground waters without treatment. The product N,N-bis (3,5-Dimethylpyrazol-1-yl methyl)-3-aminopropyl Polysiloxane (Si-C3H6NPz2) was successfully prepared. The FTIR results confirmed that the dimethylpyrazole units have been immobilized onto the surface of the modified silica gel. The adsorption experiments were conducted for a wide range of solution pH, adsorbent dosage, temperature, initial concentration and contact time. It was observed that the percentage removal of methylene blue dye decreased with an increase initial concentration and temperature while it increased with increase in solution pH, contact time and adsorbent dose. Over 82% removal efficiency of methylene blue dye was achieved after 180 min at solution pH around 10, 20°C temperature, 0.25 g weight of dose and initial concentration of 15 mg/L of 50mL MB dye solution.  Negative ∆G° values (-17.17 to -17.25 KJ/mol) indicate that the adsorption is favorable and spontaneous at these temperatures. The negative value of ∆H° (-16.66 KJ/mol) reflects an exothermic adsorption and indicates that the adsorption is favored at low temperature. The value of ∆H° was higher than those corresponding to physical adsorption. This would suggest that the adsorption process is chemical in nature. The small positive value of ∆S° (+1.78 J/mol.K) suggests that some structural changes occur on the adsorbent and the randomness at the solid/liquid interface in the adsorption system increases during the adsorption process. The results of the present study show that the prepared compound has a negative biological activity against Pseudomonas aeruginosa, Staphylococcus aurous, and Escherichia coli. 

Heavy metals are persistent pollutants in the environment. Problems associated with the cleanup of sites contaminated by metals have demonstrated the need to develop remediation technologies that are feasible, quick, and effective in a wide range of physical settings. In this study we have investigated the adsorption of Cu (II), onto red soil in single and multi-element systems as a function of soil and heavy metal concentrations. Before contamination, soils were characterized to determine particle size, pH, organic matter ...

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The kinetics of oxidation of L-cysteine by 3-di-2-pyridylketone-2-thiophenylhydrazone-iron(III), [Fe(DPKTH)2]3+ complex in acidic medium was studied spectrophotometrically at 36 C temperature. The molar ratios of DPKTH to iron(III) and iron(II) individually, were found to be [2:1] [DPKTH : iron(III)/(II)]. The reaction was stroked to be first-order with respect to iron(III) and L-cysteine, second-order with respected to DPKTH ligand and reversed second-order with respected to hydrogen ion concentration. Added salts did not affect the rate and no free radical was detected when radical detector was placed in the reaction mixture. Ethanol solvent ratio was found to effect both the initial rate and the maximum absorbance (ʎmax) of [Fe(DPKTH) 2]2+ complex. The initial rate rose when the temperature was increased which empowered to calculate the activation parameters. A suitable reaction mechanism was proposed.

The kinetics of oxidation of L-cysteine by 3-di-2-pyridylketone-2-thiophenylhydrazone-iron(III), [Fe(DPKTH) 2 ] 3+ complex in acidic medium was studied spectrophotometrically at 36 o C temperature. The molar ratios of DPKTH to iron(III) and iron(II) individually, were found to be [2:1] [DPKTH : iron(III)/(II)]. The reaction was stroked to be first-order with respect to iron(III) and L-cysteine, second-order with respected to DPKTH ligand and reversed second-order with respected to hydrogen ion concentration. Added salts did not affect the rate and no free radical was detected when radical detector was placed in the reaction mixture. Ethanol solvent ratio was found to effect both the initial rate and the maximum absorbance (λ max) of [Fe(DPKTH) 2 ] 2+ complex. The initial rate rose when the temperature was increased which empowered to calculate the activation parameters. A suitable reaction mechanism was proposed.

From an environmental engineering point of view, pharmaceuticals such as antibiotics are a group of man-made chemicals of concern entering the environment in concentrations at which, the health effects are unknown. The problem that may be created by the presence of antibiotics at low concentrations in the environment is the development of antibiotic resistant microorganisms. In this study, three pharmaceutical drugs manufactured in Palestine were studied in waste water and their adsorption in agriculture soil was studied using soil columns. During the study of soil columns, it was noted that the concentration of caffeine in leachate was higher than that of ibuprofen and amoxicillin, as caffeine has higher aqueous solubility. Ibuprofen and amoxicillin were present in leachate with very small concentrations, due to their degradation and decomposition into other substances that may be harmful, and affect the natural properties of soil, groundwater and human health. The decomposition percentages of the pharmaceuticals in the soil columns were 97.82, 97.88 and 86.52% for amoxicillin, ibuprofen and caffeine for one year’s study, respectively. For the fifteen years, the decomposition percentages were 94.04, 96.60 and 93.70% for amoxicillin, ibuprofen and caffeine, respectively.

Phenolic organic compounds are extremely highly generated from many resources which disposed to sewerage system without treatments that increase the risk of contaminating water resources. This study is focused on preparing and studying the properties of activated carbon produced from cypress fruit by chemically activation using phosphoric acid (H 3 PO 4) as an activating agent. The activated carbon used to adsorb p-nitrophenol (PNP) from the aqueous solution. Result show that the activated carbon produces from cypress fruit gives good percentage yields which reach up to 51.8%. Surface area determined by iodine number showed 524.1m 2 /g. The adsorptive properties of CFAC were investigated in terms of adsorbent dose, PNP concentration, pH, and temperature and contact time in a batch system. Results indicate that the optimum percent of PNP removal 90.9 % when adsorbent dosage 0.3g and PNP concentration 80mg/L and percentage removal of PNP increase when the concentration of PNP decrease which maximum percentage removal reach 93.2% when PNP concentration 20mg/L and 0.1g CFAC. The effect of temperature on adsorption by CFAC has also been investigated in the range of 15-45 °C. The results indicate that the temperature slightly affected effectiveness of CFAC adsorption. The results showed that equilibrium time for PNP adsorption is 150min, but most the adsorption attained within the first ten minute. Results investigate that the produced cypress fruit activated carbon (CFAC) adsorption equilibrium is represented by both Frenundlich and Langmuir equilibrium model, but Langmuir model describe very well the adsorption. The main properties of Langmuir equation can be expressed in term of separation factor, R L . The R L equal 0.053 that indicate the adsorption favorable.

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In this study we examined the adsorption, kinetics and thermodynamics of heavy metals of used engine oil that come during engine operation and forsaw the possibility of polluting soil and ground water. the effect of temperature on
adsorption was investigated in the range (15 – 45o C) and results showed that maximum removal occurred at 45C. Effect of pH indicated that maximum removal of both Zn and Pb was at pH =13. Increasing adsorbent (soil) dosage from 0.5 to 3g showed that maximum adsorption of both Zn and Pb onto soil occurred with 3 g of soil. Equilibrium concentration happened at 90 minutes. Lanqmuir and Freiundlich models were used to study adsorption process at equilibrium and the
results showed that Frenundlich is better for Zn while Lanqmuir fits better with Pb. In order to investigate adsorption behavior of Zn and Pb on soil, three kinetic models applied; Pseudo-first order, Pseudo-second order and intra- particle diffusion models were applied to fit kinetics data. The rate constants and correlation coefficients were determined for the three models. Thermodynamic parameters such as Gibbs free energy, standard enthalpy and standard entropy change were calculated for both zinc and lead.

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 fluoroquinolone 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.

Phenolic organic compounds are extremely highly generated from many resources which disposed to sewerage system without treatments that increase the risk of contaminating water resources. This study is focused on preparing and studying the properties of activated carbon produced from cypress fruit by chemically activation using phosphoric acid (H 3 PO 4) as an activating agent. The activated carbon used to adsorb p-nitrophenol (PNP) from the aqueous solution. Result show that the activated carbon produces from cypress fruit gives good percentage yields which reach up to 51.8%. Surface area determined by iodine number showed 524.1m 2 /g. The adsorptive properties of CFAC were investigated in terms of adsorbent dose, PNP concentration, pH, and temperature and contact time in a batch system. Results indicate that the optimum percent of PNP removal 90.9 % when adsorbent dosage 0.3g and PNP concentration 80mg/L and percentage removal of PNP increase when the concentration of PNP decrease which maximum percentage removal reach 93.2% when PNP concentration 20mg/L and 0.1g CFAC. The effect of temperature on adsorption by CFAC has also been investigated in the range of 15-45 °C. The results indicate that the temperature slightly affected effectiveness of CFAC adsorption. The results showed that equilibrium time for PNP adsorption is 150min, but most the adsorption attained within the first ten minute. Results investigate that the produced cypress fruit activated carbon (CFAC) adsorption equilibrium is represented by both Frenundlich and Langmuir equilibrium model, but Langmuir model describe very well the adsorption. The main properties of Langmuir equation can be expressed in term of separation factor, R L . The R L equal 0.053 that indicate the adsorption favorable.

In recent years, pesticides were used heavily in Palestine, which led to the contamination of soil and water and causing many diseases. Many studies focused on the impact of pollutants such as pesticides and oil on soil, humans, animals, plants and the environment in general.
Using column study the amount of glyphosate in soil decreases with increasing depth of soil, where it is for 0-30cm(11ppm) > 30-60cm(6ppm) > 60-100cm(2ppm) due to organic content and metal oxides founded in soil that can form stable complexes with glyphosate.
When we increased the concentration of glyphosate, the amount of glyphosate (contaminant) in leachate where found to be 25x (15.96ppm) >15x (3.91) > 5x (3ppm) column.
The behavior of glyphosate leachate fits the first order reaction and the isotherm is in according with the Freundlich adsorption equation with R2 value 0.98, k value 6.4 and n value 1.07 which indicates good adsorption to soil.