Conseguences of soil crude oil pollution on some wood properties of olive trees Chemistry | 54 2016( ػاو 3انؼذد ) 29يدهت إبٍ انهيثى نهؼهىو انصرفت و انخطبيميت انًدهذ Ibn Al-Haitham Jour. for Pure & Appl. Sci. Vol. 29 (3) 2016 Removal of Chlorpyrifos (Dursban) Pesticide from Aqueous Solutions using Barley Husks Shaymaa Khalaf Ghati Intidhar Dawood Sulaiman Najwa Issac Abdulla Dept. of Chemistry/ College of Education for Pure Sciences ( Ibn Al-Haitham) University of Baghdad Receved in:27/January/2016,Accepted in:6/March/2016 Abstract The removal of chlorpyrifos pesticide from aqueous solutions was achieved by adsorption using low cost agricultural residue as adsorbent surface; barley husks. Several variables that affect the adsorption were studied including contact time, adsorbent weight, pH, ionic strength, particle size and temperature. The absorbance of the solution before and after adsorption was measured by using UV-Visible spectrophotometer. The equilibrium data was suitable with Langmuir model of adsorption and the linear regression coefficient R 2 = 0.9785 at 37.5°C was used to knowledge the best fitting isotherm model. The general shape of the adsorption isotherm of chlorpyrifos on barley husks consistent with (H3-type) on the Giles classification. Several thermodynamic functions such as (Gibb's free energy, enthalpy and entropy) of the on-going adsorption process have also been estimated. ( H°=0.0080 ) ,( The results of the pesticide adsorption process on barley husks indicated that the adsorption process is endothermic. The positive values of propose the increasing randomized. The negative values indicated the spontaneous process of adsorption. Keywords: adsorption, chlorpyrifos, Langmuir model, Freundlich model, thermodynamic, barley husks adsorbent. Chemistry | 55 2016( ػاو 3انؼذد ) 29يدهت إبٍ انهيثى نهؼهىو انصرفت و انخطبيميت انًدهذ Ibn Al-Haitham Jour. for Pure & Appl. Sci. Vol. 29 (3) 2016 Introduction Pollution caused by any (biological, physical and chemical side-effects) of people industrial or social activities. It can impact the (rivers, seas, atmosphere or soil). Water pollutants such as chlorinated hydrocarbon pesticides are toxic, non-biodegradable and harmful to people health [1, 2]. Pesticides are introduced into the environment by disposal, application, and a spill [3]. Pesticides freed into environment are present in aquatic systems. They are discovering at low plateau and usually happen in the form of complex mixtures [4]. Filter of pesticides, applied to agricultural ground, is one of the major sources for organic pollution in some water streams [5]. The pesticides can reach water- bearing aquifers below ground from applications onto crop fields of contaminated surface water. Pesticide contamination of ground water is a subject of international importance because ground water is used for drinking aim. Before the mid-1970s, it was thought that ground acted as a defensive filter that stopped the pesticides from reaching ground water [6]. The constant exposure of pesticides to non-target species may lead to induce toxicity once it crosses the threshold limit in the system [7, 8]. The different stages involved in pesticide cycle are illustrated in Figure (1). Waste water containing pesticides and toxic compounds need very careful treatment before discharge into receiving bodies of water. Several (physical, chemical, physico -chemical and biological methods) have been developed to remove contaminants from wastewater. These methods involved; coupled-column liquid chromatography/electro spray ionization [9], gas chromatography [10], solid-liquid extraction [11], HPLC [12- 14], electrochemical methods [15- 17], stripping voltammetry [18], biodegradation and adsorption treatment [19, 20]. Adsorption process has been found one of the most popular physico- chemical treatment methods for take out contaminants [21, 22]. The aim of the present study is to find a low-cost eco-friendly agricultural residue adsorbent surface for the elimination of chlorpyrifos contaminant from waste water. Experimental Apparatus 1. A double beam UV-Visible spectrophotometer, Shimadzu 1800 (Japan) with 1 cm matched quartz cells was used for the absorbance measurement. 2. Electronic balance, Radwage AS220/C/1 was used for weighing the samples. 3. Thermostated water bath shaker, LabTech LSB-045S (Korea). 4. Centrifuge, Hettich EBA20 (Germany), 6000 rpm. 5. pH- meter with combined glass electrode. Materials and Methods The adsorbate (Chlorpyrifos) Chlorpyrifos (0,0-diethyl-0-3,5,6-trichoro-2-pyridylphosphorothioate) is a substance used for killing insects, generally famous as Dursban and Lorsban [23]. Chlorpyrifos is highly toxic to all kinds of life such as birds, fresh water fishes, marine organisms and honeybees [24]. The chemical and physical properties of chlorpyrifos are listed in Table (1). The Adsorbent (Barley husks) Barley husks used as adsorbent throughout this study were obtained from Isaaqi region in Salahuddin province-Iraq. The husks were washed several times with amounts of distilled water to take out (soluble materials or dust), and were dryish in an oven at 40 °C. They were then grinded and sieved by using (75, 150 and 250) m sieves. Particles of the size (75 m) was used Chemistry | 56 2016( ػاو 3انؼذد ) 29يدهت إبٍ انهيثى نهؼهىو انصرفت و انخطبيميت انًدهذ Ibn Al-Haitham Jour. for Pure & Appl. Sci. Vol. 29 (3) 2016 as adsorbent surface in all experiments of this work. The qualitative analysis for active chemical compounds of barley husks is listed in Table (2). Chlorpyrifos Stock Solution (100 mg/L) The stock solution was prepared by dissolving 0.1000g of chlorpyrifos pesticide in 1L of distilled water. The stock solution was protected from light and stored at 25°C. The Batch Mode of Adsorption Studies The experiments were done to define the impact of contact time, weight of adsorbent , pH, ionic strength and partical size of adsorbent. Absorbance values of solutions of concentrations range (10- 80) mg/L were measured at selected λmax (265 nm) and plotted against the concentration of pesticide, Figure (2) shows the calibration curve of chlorpyrifos. Percentage removal of pesticide (R%) and (Qe) was calculated using Eq.1 and 2 respectively [28, 29]. R% = *100 ……………………….(1) Qe ……………………….(2) Where: m: The weight of barley husks (g). Co : The initial concentration of chlorpyrifos (mg/L). Ce: The equilibrium concentration of chlorpyrifos (mg/L). V: The volume of chlorpyrifos solution ( L ). Factors Affecting Adsorption Process Contact Time In a set of conical flasks 10 ml of a fixed concentration (80 mg/L) and pH (7.3) of chlorpyrifos solution was shaken with 0.2 g of barley husks at 37.5 °C. The solution was withdrawn from the shaker for regular time intervals of ( 5, 10, 20, 30, 45, 60, 90, 120 and 150 min) , and centrifuged at 3000 rpm for 20 minutes, the concentration of adsorbate solutions were measured spectrophotometrically. Adsorbent Weight In a set of conical flasks various weights of barley husks [ 0.1, 0.2, 0.3, 0.4, 0.5 , 0.6] g were mixed with 10 ml of a fixed concentration of chlorpyrifos solution 80 mg/L and pH= 7.3, the mixture was shaken at a specified temperature 37.5 °C, then centrifuged at 3000 rmp for 20 minutes to separate the adsorbent. pH Effect Adsorption experiment were carried out at different pH values (1.5, 3.1, 5.4, 7.3, 9.4 and 11.3). The pH of the solutions were adjusted by adding the required amounts of 0.1 M HCl and NaOH. All other parameters were kept constant while carrying out the experiment. Effect of Ionic Strength The effect of the addition (0.1, 0.2, 0.3, 0.4 and 0.5) M of NaCl to solutions containing fixed concentration of adsorbate 80 mg/L and pH= 7.3 equilibrated with (0.2g) of barley husks were exact under the experimental conditions substantive before. Chemistry | 57 2016( ػاو 3انؼذد ) 29يدهت إبٍ انهيثى نهؼهىو انصرفت و انخطبيميت انًدهذ Ibn Al-Haitham Jour. for Pure & Appl. Sci. Vol. 29 (3) 2016 Particle Size Effect The effect of particle size (surface area) on adsorption was studied by using four different sizes of sieves (75 ,150, 250 and 300 ). These experiments were performed by using a fixed concentration of adsorbate 80 mg/L and pH= 7.3 with different particle sizes of the same weight of adsorbent 0.2 g under the same experimental conditions described above. Temperature Effect The adsorption procedure was purified in the same way at various temperatures (10.0, 25.0 and 37.5 °C) to appreciate the basic thermodynamic parameters. Result and Discussion FTIR of the Adsorbent Surface Fourier Transform Infrared Spectroscopy (FTIR) was performed to give the chemical active groups present in the barley husks. The spectrum of the adsorbent was obtained using (KBr) technique. FTIR of assignment groups of barley husks is shown in Figure (3). The spectrum shows broad absorption peaks at (3500- 3100) cm -1 , corresponding to the overlapping of –OH and –NH peaks. The peaks in the range (1550- 800 cm -1 ) can be attributed to the stretching of the C-N and C-O, and to the bending of the N-H, C-H and O-H groups [30- 32]. Equilibrium Time The effect of contact time on the chlorpyrifos adsorbed per unit of barley husks was studied at 37.5 °C. Table (3) , Figure (4) show the values of Qe and Ce of 80 mg/L chlorpyrifos solution at 37.5 °C. An acute change in adsorption is notice at beginning and thereafter a slow increase was notice in adsorption with increasing time up to 90 minutes, after which a maximum value of adsorption is attained. The time of 90 minutes is treat as the optimum contact time. Adsorbent Weight The effect of adsorbent dosaget on the R% of chlorpyrifos adsorbed was calculated with 10ml of 80 mg/L initial concentration of chlorpyrifos the results are shown inTable (4) and Figure (5). It is obvious that R% of chlorpyrifos increased with increasing the adsorbent weight. This may be due to the increase in availability of surface active sites resulting from increased dose. Effect of PH The effect of pH on the amount of chlorpyrifos adsorbed was studied by varying the initial pH under constant process parameters at equilibrium conditions. Table (5) and Figure (6). The extent of adsorption may( increase, decrease, or remain unchanged) as a result of changing the pH [33]. The results in Table (5) indicate that the adsorption capacity in acidic medium increase with increasing pH up to 7.3, the maximum adsorption from the original solution takes place at pH value of 7.3. Beyond this value the increase in pH was accompanied by a decrease in adsorption capacity. Ionic Strength The effect of ionic strength on adsorption uptake of chlorpyrifos on barley husks has been studied by adding variable concentrations of sodium chloride (0.1, 0.2, 0.3, 0.4 and 0.5) M. In a previous study for our group at this department [34], the following empirical equation was suggested for the relationship between the ionic strength (I) and the amount of adsorption (Qe). Chemistry | 58 2016( ػاو 3انؼذد ) 29يدهت إبٍ انهيثى نهؼهىو انصرفت و انخطبيميت انًدهذ Ibn Al-Haitham Jour. for Pure & Appl. Sci. Vol. 29 (3) 2016 Qe = Qe° - AI -------------------(3) Where: Qe°: the amount of adsorption at (I=zero] A: Empirical constant for the system. I: Ionic strength. It was found that the effect of the ionic strength (I) on the adsorption quantity (Qe) at equilibrium is a linear relationship as indicated in Table (6) and Figure (7). Generally, the rise in the salt concentration resulted in a lowering of chlorpyrifos removal by barley husks. This result show that the adsorption activity decreases when NaCl concentration increases in the chlorpyrifos solution, which could be assign to the competitive effect between pesticide ions and the salt ions for the locations ready for the adsorption process [35]. Particle Size The effect of particle size on adsorption process was studied by using a fixed concentration (80 mg/L) of chlorpyrifos solution as an adsorbate and four samples of a same weight of barley husks (0.2 g) of different particle sizes (75, 150, 250 and 300 m). Table (7) and Figure (8) illustrate the influence of particle size of the adsorbent on the amount of chlorpyrifos adsorbed by barley husks at (37.5 °C). The results indicate that the maximum quantity of chlorpyrifos which was adsorbed on the barley husks followed the order: 75 m > 150 m > 250 m > 300 m. Hence the increase of the surface area (decrease in the particle size) leads to an increase in the adsorption uptake of chlorpyrifos on the barley husks, such an increase can be attributed to the increase in the active sites exposed to the adsorbate [37, 38]. Adsorption Isotherms Adsorption isotherm can be realized as the relation between Qe and Ce at fixed temperature. The study of the adsorption isotherm give great and advantageous information to depict the nature of adsorption process and its condition and knowing about the amount of pesticides adsorbed with its concentration in the adsorption process. Adsorption of chlorpyrifos from aqueous solution on barley husks was studied at three temperatures (10.0, 25.0, and 37.5 °C) keeping the other parameters of adsorption unchanged. The resulst of this study represented by the initial concentration of adsorbate (Co), the equilibrium concentration (Ce) and the quantity adsorbed (Qe) are indicated in Table (8) .The values of (Qe) were plotted versus (Ce) to take out the adsorption isotherms as shown in Figure (9). The results showed an increase in adsorptive capacities of barley husks as the concentration of pesticide increases until reaching a limited value. The general shape of the adsorption isotherm of chlorpyrifos on barley husks consistent with (H3-type) on the Giles classification which indicates high affinity between the adsorbate and adsorbent even in very dilute solution [38]. The experimental adsorption data were applied to the empirical Langmuir isotherm (Eq. 4) [39]. and Freundlich isotherm (Eq. 5) [40] equations = + ( ----------------(4) logQe = log Kf + log Ce ----------------(5) Chemistry | 59 2016( ػاو 3انؼذد ) 29يدهت إبٍ انهيثى نهؼهىو انصرفت و انخطبيميت انًدهذ Ibn Al-Haitham Jour. for Pure & Appl. Sci. Vol. 29 (3) 2016 These results indicated the applicability of Langmuir and Freundlich isotherms according to the values of linearity (R 2 ) as shown by the linear relationship of (Ce/Qe) versus (Ce) and (log Qe) versus (log Ce) at different temperatures in Tables (9), (10) and Figures (10), (11). The Langmuir and Freundlich constant empirical values were obtained from the linear equation at different temperatures. The values are summarized in Tables (11), (12). Thermodynamic of Adsorption Process The Thermodynamic functions related to the adsorption of pesticide, like, Gibbs free energy change , enthalpy change and entropy change . The change in free energy could be determined from the following equations [41]. G = -RT ln Kads ---------------- (6) ln Kads = (- H / RT) + ( S / R) ---------------- (7) G = H -T S ---------------- (8) Where R is the gas constant (8.314 J/mol.deg), Kads is adsorption equilibrium constant which was calculated at each temperature (T) from the following equation [42]. Kads --------------(9) Where Qe is the amount adsorbed (mg/g), Ce is the equilibrium concentration of the adsorbate expressed in mg/L. The values of and were determined from the slope and intercept of the linear plot of (ln Kads) vs. (1000/T). The results obtained are given in Table (13) and Figure (12). , and values were listed in Table (14). 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Table (1): Physical and chemical characteristics of chlorpyrifos [25, 26] IUPAC name 0,0-diethyl-0-3,5,6-trichoro-2-pyridyl phosphorothioate Trade name Dursban or Lorsban Chemical structure N Cl Cl Cl O P OC2H5 OC2H5 S Chemical formula C9H11Cl3NO3PS Molecular weight 350.59 g/mol Solubility In water 2 mg/ L (25°) Poling point 100 °C Colour White Chemistry | 62 2016( ػاو 3انؼذد ) 29يدهت إبٍ انهيثى نهؼهىو انصرفت و انخطبيميت انًدهذ Ibn Al-Haitham Jour. for Pure & Appl. Sci. Vol. 29 (3) 2016 Table (2) The active chemical compounds of barley husks [27] Active organic compound Barley husks Saponins + Alkaloids + Resins + Coumarins - Flavones + Tannins + Terpenes - Table (3): The variation of Qe and Ce values with time in the adsorption process Time (min) Ce (mg/L) Qe (mg/g) 5 7.2439 3.6378 20 7.7317 3.6134 30 7.8537 3.6073 60 8.0976 3.5951 90 8.2195 3.5890 120 8.2195 3.5890 150 8.2195 3.5890 Table (4): The quantity of adsorbent and R% values for (80 mg/L) chlorpyrifos pesticide Weight of adsorbent (g) Ce R% 0.1 31.6341 60.4573 0.2 26.7561 66.5549 0.3 20.7805 74.0244 0.4 18.0976 77.3780 0.5 15.1707 81.0366 0.6 11.8780 85.1524 Table (5): The values of R% and Ce for (80 mg/L) chlorpyrifos pesticide at different pH pH Ce R% 1.5 30.6585 61.6768 3.1 21.7561 72.8049 5.4 14.1951 82.2561 7.3 9.4390 88.2012 9.4 32.0000 60.0000 11.3 47.9756 40.0305 Table (6): The effect of addition of different concentrations of NaCl on the adsorption quantity of (80 mg/L) chlorpyrifos pesticide at 37.5 C°. Conc. Of NaCl (M) Ce Qe 0.1 13.0976 3.3451 0.2 16.1463 3.1927 0.3 18.9512 3.0524 0.4 21.0244 2.9488 0.5 22.8537 2.8573 Chemistry | 63 2016( ػاو 3انؼذد ) 29يدهت إبٍ انهيثى نهؼهىو انصرفت و انخطبيميت انًدهذ Ibn Al-Haitham Jour. for Pure & Appl. Sci. Vol. 29 (3) 2016 Table (7): Adsorption quatities for (80 mg/L), chlorpyrifos pesticide adsorbed by different particle sizes of barley husks at 37.5 C° Particle size ( Ce Qe 75 8.9512 3.5524 150 11.7561 3.4122 250 14.5610 3.2720 300 17.8537 3.1073 Table (8): Data of pesticide uptake by barley husks at different temperature and pH 7.3 Co (mg/L) 10.0 °C 25.0 °C 37.5 °C Ce Qe Ce Qe Ce Qe 10 0 0.5 0 0.5 0 0.5 20 0 1 0 1 0 1 30 0 1.5 0 1.5 0 1.5 40 0 2 0 2 0 2 50 6.8780 2.1561 6.0244 2.1988 0 2.5 60 9.5610 2.5220 8.8293 2.5585 6.7561 2.6622 70 10.6585 2.9671 9.5610 3.0220 7.8537 3.1073 80 11.3902 3.4305 10.2927 3.4854 8.9512 3.5524 Table (9): Adsorption quantities of chlorpyrifos on barley husks at various temperatures and pH 7.3 according to the application of Langmuir equation Co (mg/L) 10.0 °C 25.0 °C 37.5 °C Ce (mg/L) Qe (mg/g) Ce/Qe (g/L) Ce (mg/L) Qe (mg/g) Ce/Qe (g/L) Ce (mg/L) Qe (mg/g) Ce/Qe (g/L) 10 0 0.5 0 0 0.5 0 0 0.5 0 20 0 1 0 0 1 0 0 1 0 30 0 1.5 0 0 1.5 0 0 1.5 0 40 0 2 0 0 2 0 0 2 0 50 6.8780 2.1561 3.1900 6.0244 2.1988 2.7399 0 2.5 0 60 9.5610 2.5220 3.7910 8.8293 2.5585 3.4510 6.7561 2.6622 2.5378 70 10.6585 2.9671 3.5922 9.5610 3.0220 3.1638 7.8537 3.1073 2.5275 80 11.3902 3.4305 3.3203 10.2927 3.4854 2.9531 8.9512 3.5524 2.5198 Chemistry | 64 2016( ػاو 3انؼذد ) 29يدهت إبٍ انهيثى نهؼهىو انصرفت و انخطبيميت انًدهذ Ibn Al-Haitham Jour. for Pure & Appl. Sci. Vol. 29 (3) 2016 Table (10): Adsorption quantities of chlorpyrifos on barley husks at various temperatures according to the application of Freundlich equation Co (mg/L) 10.0 °C 25.0 °C 37.5 °C logCe logQe logCe logQe logCe logQe 10 …….. -0.3010 …….. -0.3010 …….. -0.3010 20 …….. 0 …….. 0 …….. 0 30 …….. 0.1761 …….. 0.1761 …….. 0.1761 40 …….. 0.3010 …….. 0.3010 …….. 0.3010 50 0.8375 0.3337 0.7799 0.3422 …….. 0.3979 60 0.9805 0.4017 0.9459 0.4080 0.8297 0.4252 70 1.0277 0.4723 0.9804 0.4803 0.8951 0.4924 80 1.0565 0.5354 1.0125 0.5423 0.9519 0.5505 Table (11): The Langmuir constants empirical values and the correlation coefficients for the removal of chlorpyrifos by barley husks at various temperatures Temperature (°C) a (mg/g) b (L/g) R 2 10.0 2.9189 3.8670 0.9491 25.0 2.9700 4.3384 0.9504 37.5 3.1726 15.9236 0.9785 Table (12): The Freundlich constants empirical values and the correlation coefficients for the removal of chlorpyrifos by barley husks at various temperatures Temperature (°C) n Kf R 2 10.0 2.4510 1.0988 0.6020 25.0 2.2962 1.0995 0.6120 37.5 2.3652 1.2996 0.4660 Table (13): The effect of temperature on the thermodynamic equilibrium constant (k) for the removal of chlorpyrifos by barley husks Temperature (°C) Temperature 1000/T Ce Qe k ln k 10.0 283 3.5335 2.20 5.50 1.7047 25.0 298 3.3557 8.0 2.40 6.00 1.7918 37.5 310.5 3.2206 3.00 7.50 2.0149 Chemistry | 65 2016( ػاو 3انؼذد ) 29يدهت إبٍ انهيثى نهؼهىو انصرفت و انخطبيميت انًدهذ Ibn Al-Haitham Jour. for Pure & Appl. Sci. Vol. 29 (3) 2016 Table (14): Values of thermodynamic functions for the adsorption of chlorpyrifos on barley husks at different temperatures Temperature (K) (kJ/mol) (kJ/mol) (J/mol.k) 283 -4.0110 +14.2014 298 -4.4392 +0.0080 +14.9235 310.5 -5.2015 +16.7778 Figure (1): The different stages involved in pesticide cycle Figure (2): Calibration curve of chlorpyrifos Figure (3): FTIR spectrum of barley husks Figure (4): Effect of contact time on the adsorption of chlorpyrifos by the adsorbent 0 1 2 3 4 5 0 20 40 60 80 100 120 140 160 Tim e (m in) Q e ( m g /g ) y = 0.0082x - 0.0354 R 2 = 0.99 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0 20 40 60 80 100 Co (mg/L) A Chemistry | 66 2016( ػاو 3انؼذد ) 29يدهت إبٍ انهيثى نهؼهىو انصرفت و انخطبيميت انًدهذ Ibn Al-Haitham Jour. for Pure & Appl. Sci. Vol. 29 (3) 2016 Figure (5): Effect of adsorbent weight on adsorption of chlorpyrifos by the adsorbent Figure (6): Effect of pH on adsorption of chlorpyrifos by the adsorbent Figure (7): Effect of ionic strength on the adsorption of chlorpyrifos on the adsorbent Figure (8): Effect of adsorbent particle size on the adsorption Figure (9): Adsorption isotherm of chlorpyrifos on the adsorbent at different temperatures Figure (10): Linear form of Langmuir isotherm of chlorpyrifos on the adsorbent at different temperatures 30 40 50 60 70 80 90 100 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 Weight (g) R % 20 30 40 50 60 70 80 90 100 0 2 4 6 8 10 12 PH R % y = -1.2195x + 3.4451 R 2 = 0.9879 2.8 2.9 3 3.1 3.2 3.3 3.4 0 0.1 0.2 0.3 0.4 0.5 0.6 I Q e ( m g /g ) 3 3.1 3.2 3.3 3.4 3.5 3.6 0 50 100 150 200 250 300 350 particle size Q e ( m g /g ) 0 0.5 1 1.5 2 2.5 3 3.5 4 0 2 4 6 8 10 12 Ce (m g/L) Q e ( m g /g ) 283 K 298 K 310.5 K 0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 0 2 4 6 8 10 12 Ce (mg/L) C e /Q e ( g /L ) 283 K 298 K 310.5 K Linear (283 K) Linear (298 K) Linear (310.5 K) Chemistry | 67 2016( ػاو 3انؼذد ) 29يدهت إبٍ انهيثى نهؼهىو انصرفت و انخطبيميت انًدهذ Ibn Al-Haitham Jour. for Pure & Appl. Sci. Vol. 29 (3) 2016 Figure (11): Linear form of Freundlich isotherm of chlorpyrifos on the adsorbent at different temperatures Figure (12): Plot of lnk against reciprocal absolute temperature for adsorption of chlorpyrifos on the adsorbent -0.4 -0.3 -0.2 -0.1 0 0.1 0.2 0.3 0.4 0.5 0.6 0 0.2 0.4 0.6 0.8 1 1.2 log Ce lo g Q e 283 K 298 K 310.5 K Linear (283 K) Linear (298 K) Linear (310.5 K) y = -1.1283x + 5.6286 R 2 = 0.8274 0 0.5 1 1.5 2 2.5 3.2 3.25 3.3 3.35 3.4 3.45 3.5 3.55 1000/T ln K Chemistry | 68 2016( ػاو 3انؼذد ) 29يدهت إبٍ انهيثى نهؼهىو انصرفت و انخطبيميت انًدهذ Ibn Al-Haitham Jour. for Pure & Appl. Sci. Vol. 29 (3) 2016 ازانة مبيذ انكهوربايريفوس )انذورسبان( مه انمحانيم انمائية باستعمال قشور انشعير شيماء خهف غاطي اوتظار داود سهمان وجوى اسحق عبذ هللا خايؼت بغذاد /كهيت انخربيت نهؼهىو انصرفت )ابٍ انهيثى( /لطى انكيًياء 2012/ارار/2قبم في: ،2012/كاوون انثاوي/22استهم في: انخالصة حى ازانت يبيذ انكهىربايريفىش )انذورضباٌ( يٍ انًحانيم انًائيت باضخخذاو لشىر انشؼير ضطح ياز يٍ بمايا َباحيت واطئ انكهفت. درضج انؼذيذ يٍ انًخغيراث انًؤثرة في ػًهيت االيخساز وانًخضًُت زيٍ االحساٌ, وزٌ انًادة انًازة, انذانت انحايضيت, انشذة ًطاحت انططحيت نهًادة انًازة, وحأثير درخت انحرارة في ػًهيت االيخساز. حى لياش ليى االيخصاص نهًحهىل لبم وبؼذ االيىَيت, ان فىق انبُفطديت. اٌ ايسوثيرياث االيخساز حخضغ انى يؼادنت الَكًاير واٌ انشكم انؼاو -االيخساز باضخخذاو يطيافيت االشؼت انًرئيت . حى حطاب انذوال انثريىدايُاييكيت االضاضيت نؼًهيت االيخساز وانًخضًُت Giles( يٍ حصُيف (H3ناليسوثيرو يخىافك يغ انصُف االَثانبي , االَخروبي , وطالت خيبص انحرة. اظهرث انُخائح اٌ ػًهيت ايخساز يبيذ انذورضباٌ ػهى ضطح لشىر انشؼير يٍ انُىع ظى.انًاص نهحرارة واٌ انؼًهيت يٍ انُىع انؼشىائي غير انًُخ االيخساز, يبيذ انذورضباٌ, ًَىرج الَكًاير, ًَىرج فريُذنش, انذوال انثريىديُاييكيت, لشىر انشؼير.: انكهمات انمفتاحية