An-Najah Staff

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.

Batch and isotherm studies were carried out to compare the effectiveness of decaying leaves of cypress (Cupressus sempervirens), cinchona (Eucalyptus longifolia) and pine (Pinus halepensis) to adsorb lead from its aqueous solution and to study the leaf interaction effects. Lead removal increased with increasing concentrations of both lead ions and the plant leaves employed. Removal efficiency of leaves followed the decreasing order: pine>cypress>cinchona. While cinchona leaves showed an antagonistic effect on the removal efficiencies of cypress, pine, and a combination of cypress and pine leaves, the effect of cypress on the removal efficiency of pine leaves was additive. The adsorption of lead by cypress and cinchona leaves was well defined by both the Freundlich and Langmuir isotherms, but only the Freundlich isotherm was adopted for pine leaves. Desorption of lead from leaves upon standing in deionized water was minimal.

The inhibition of ethyl 2-(4-(2-ethoxy-2-oxoethyl)-2-p-tolylquinoxalin-1(4H)-yl) acetate (Q3) on the corrosion of carbon steel in 1.0 M HCl at 308-343 K was studied by gravimetric method. Results obtained show that Q3 acts as inhibitor for carbon steel in hydrochloric solution. The inhibition efficiency was found to increase with increase in Q3 but decreased with temperature, which is suggestive of physical adsorption mechanism although chemisorption may play a part. The adsorption of Q3 onto the carbon steel surface was found to follow the Langmuir adsorption isotherm. Both kinetic parameters (activation energy, pre-exponential factor, enthalpy of activation and entropy of activation) and thermodynamics of adsorption (enthalpy of adsorption, entropy of adsorption and Gibbs free energy) were calculated and discussed.

The detailed study of corrosion behaviour of copper in 2M nitric acid solution in the presence and absence of 2-(4-(2-ethoxy-2-oxoethyl)-2-p-tolylquinoxalin-1(4H)-yl)acetate (Q1) was investigated using weight loss method at various temperatures from 303 to 343 K. The inhibitor showed 97% inhibition efficiency at its optimum concentration 10-3M at 303K and decreased at higher temperatures. The thermodynamic parameters such as, equilibrium constant, adsorption heat and adsorption entropy were obtained. The various parameters of activation determining the kinetic data such as energy, enthalpy and entropy at different concentrations of the inhibitor were evaluated and discussed. The adsorptive behaviour of Q1 followed Langmuir-type isotherm. The standard free energies of adsorption were negative at different temperatures tested, reûecting better inhibition performance.

N-1-Naphthylethylenediamine dihydrochloride monomethanolate (N-NEDHME) was tested as a corrosion inhibitor for copper in 2 M HNO3 solution using the standard gravimetric technique at 303–343 K. N-NEDHME acts as an inhibitor for copper in an acidic medium. Inhibition efficiency increases with increase in concentration of N-NEDHME but decreases with a rise in temperature. Thermodynamic parameters such as adsorption heat ( \UpdeltaH∘ads ), adsorption entropy ( \UpdeltaS∘ads ) and adsorption free energy (\UpdeltaG∘ads) were obtained from experimental data of the temperature studies of the inhibition process at five temperatures ranging from 303 to 343 K. Kinetic parameters activation such as Ea , \UpdeltaH∘a , \UpdeltaS∘a and pre-exponential factors have been calculated and are discussed. Adsorption of N-NEDHME on the copper surface in 2 M HNO3 follows the Langmuir isotherm model.

The purpose of this study was to investigate the impact of biological oxygen demand (BOD) on soil and drinking water in West Bank. This study will give us a conclusion about ground water contamination from solid waste and sewage water.

The study was performed on two soil samples brought from Jericho and Talkarem. The physical and chemical properties of the two soil samples were analyzed. The experiment was studied using physical simulation by using different soil column techniques and making some estimation using the amount of rainfall each year and the dimensions of those columns. The study was conducted between April and May, 2009. The concentration of BOD in the leachate was found to increase with time in both types of soil, in April the BOD concentration was higher in the leachate from Jericho soil than Talkarem soil, but in May the BOD concentration was higher in Talkarem soil than Jericho soil. The concentration of BOD in the leachate collected from blank column was decreasing with time, the dissolved oxygen (DO) was decreasing with increasing BOD concentration in both soils.

The total dissolved solids (TDS) concentration in the leachate was decreasing in both soils with time. The BOD concentration was increasing in the soil layers from top to the bottom in both soils (Talkarem and Jericho), but BOD was higher in Talkarem soil in each layer compared with that in Jericho soil layers. The TDS level in Talkarem soil layers was higher than in Jericho soil layers. The total nitrogen (TN) concentration in soil layers increases with depth and with time during water addition in the blank column but decreases in the soil layers in the columns where BOD was added.

The effect of temperature on the corrosion behavior of copper in 2M nitric acid solution in the presence and absence of 5-(2,6-dichlorobenzyl)-6-methylpyridazin-3(2H)-one (P3) has been investigated by weight loss method. The inhibitory effect increases with increasing inhibitors concentration and decreases with rise of temperature from 303 to 343K. Adsorption follows the Langmuir isotherm with negative values of free enthalpy suggesting a spontaneous adsorption process. Other thermodynamic parameters such as, equilibrium constant, adsorption heat and adsorption entropy were obtained. The various parameters of activation determining the kinetic data such as energy, enthalpy and entropy at different concentrations of the inhibitor were evaluated and discussed.

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.