Ground Water in Certain Sites in Egypt and Its Treatments Using a New Modified Ion Exchange Resin — Characterization of Water and Modified Ion Exchange

The present work is a comprehensive of drinking water quality. Eleven groundwater samples were taken from various rural regions of Egypt, the groundwater samples were investigated for chemical, radiometric and heavy metals analyses, the major cations including; sodium ( Na ), potassium ( K ), calcium ( 2 Ca  ) and magnesium ( ) ions species, the major anions of chloride ( 2 Mg  Cl ), sulphate ( 4 SO  ), nitrite ( 2 NO  ), phosphate ( 4 PO  ). Radiometric analyses in water expressed as the gross alpha and beta activity concentrations, heavy metals analyses including arsenic ( 3 As  ), lead ( ), cobalt ( ), manganese ( ), iron ( 2 Pb  2 Co  2 Mn  3 Fe  ) and cadmium ( 2 Cd  ) ions. The groundwater samples were found to contain high concentrations of heavy metals than the limited values of the world health organization (WHO). Heavy metals speciation were performed using MinteqA2 geochemical code. A modified exchange resin was prepared by polymerization of the condensed dioxalayl p-sulphanilamide with phenol, this ion exchange resin was examined by the different techniques such as; x-ray diffraction, infra red spectra (IR), and electronic microscopic, it was found a good adsorbent material that used for the reduction of heavy metals from contaminated groundwater samples.


Introduction
Heavy metals and radionuclides can enter into surface and groundwater from a variety sources, Water pollution is thus a consumpolitan problem that need urgent attention [1][2][3][4].large amount of heavy metals and radionuclides can introduced into water body through untreated and treated liquid wastes.The origin of heavy metals contamination in drinking water lies in the illegal disposal of industrial effluents, which eventually find their way into underground aquifers.It is expected that concentration of heavy metals in drinking water will increase and their removal will be needed a great effort in future.Various treatment have been employed to reduce heavy metals from aqueous solutions.Conventional techniques usually involve application of various process such as precipitation, filtration solvent extraction and ion exchange [5].Cation exchange resin is to be useful for the removal small concentrations of heavy metals from aqueous solutions.A number of investigators have been used ion exchange materials for the removal of inorganic metal ions such as Pb, Cu, Zn, Cd and Ni from aqueous solutions [5][6][7][8].The purpose of the present study is to give characterization of groundwater samples at certain region in Egypt, and to clean up these contaminated groundwater samples that may be used for human consumer by using a synthetic ion exchange resin.

Chemicals and Apparatus
All chemical reagents are used in the experimental work are analytical grade.Inductive couple plasma, atomic emission spectrometry (ICP-AES) apparatus (France) is installed at the chemical laboratory, Second Research Reactor, Atomic Energy Authority, Egypt.Low back-ground alpha and beta detector (Sophine) apparatus is obtained from Germany, it was used for the measurements of gross alpha and beta activity concentrations in the groundwater samples.The infra-red measurements were carried out using Schimatzu FTIR-430 Jasco spectrometer (Japan) with KBr disk technique.

Radiometric Analyses
The groundwater samples were analyzed for the gross alpha (), and gross beta () activity concentrations (Bq/l), these analyses are determined using low background alpha and beta spectroscopy.

The Modified Ion Exchange Resin Preparation
The modified ion exchange resin is prepared in the current study by polymerization of the condensed dioxalayl p-sulphanilamide with phenol, excess of formaldehyde aqueous solution was inserted drop by drop to complete the chemical reaction.The former complex compound is prepared by the reaction of oxalic acid with sulphanilic acid using Dean and Stark apparatus (Figure 2).The following procedures (a & b) are used to prepare this cation exchange resin.

A-Preparation of Dioxaloyl Para
Sulphanilamide Dioxaloyl para sulphanilamide is prepared using Dean and Stark apparatus, oxalic acid (2 mole) and sulphanilic acid (1 mole) are introduced in the dean and stark apparatus using xylene as a reaction medium.Water produced from condensation reaction of carboxylic group (from oxalic acid) and amino group (from sulphanilic acid) are collected in side tube in the dean and stark apparatus.After the collection of the physical quantity of water, the reaction was stopped and the solid material was formed.This reacting product was separated, filtrated from xylene, dried in an oven at 140˚C to remove traces of xylene then, it washed with warm distilled water at 40˚C to remove the unreacted oxalic acid.Finally, this product is dried in an oven at 70˚C till a constant weight was given 0.1 M NaOH and HCl aqueous solutions, the exchangeable ions (meq/g) are plotted as a function of the different pH values [9].
The dry solid material was recrystallized from distilled water and dried (c.f.Scheme 1).

B-Preparation of the Modified Phenolic Resin
2.6.2.IR, XRD and SEM 13.6 g of the produced crystalline solid was added to 300 ml of acetic acid, this mixture was stirred well by a glass rod. 25 g of phenol was added to the mixture then 30 ml of concentrated H 2 SO 4 aqueous solution was followed by addition 67.5 g formaldehyde to the previouse mixture drop wisely.the mixture (exothermic reaction) was left to gain the room temperature.The produced solid was filtered and washed repeatedly to attain pH 7. The solid phase was separated, dried at 110˚C, grinded and sieved, the desired grain size distribution was given as adsorbent for the sorption experiments.
Approximately 1.0 mg of the modified ion exchange resin sample was used for pellet preparation with 60 mg KBr, then thermal treatment of the pellets was heated in an oven at 80˚C for 24 hours to reduce the humidity content in the sample are carried out to prevent the overlapping between water and carboxyl group bands in the spectrum.X-ray diffraction pattern of the prepared ion exchange resin as well as electronic microscopic were also examined

Sorption Experiments 2.6. Identification of the Modified Ion Exchange Resin
A known weight (0.01 to 0.2 g) of the dry synthetic ion exchange sample was shaken at 180 rpm with a constant volume (50 ml) of the natural groundwater sample in 100 ml polyethylene bottles.After 24 hours, an equilibrium was attained, the solid phase was separated from the aqueous phase by centrifugation at 180 rpm for 30 minutes.
The aqueous phase of each sample was filtered and analyzed for heavy metals such as, As, Cd, Cr, Co, Fe, Mn, and Pb using ICP-AES.The metal ion removal expressed The modified ion exchange resin solid material is characterized by different techniques such as Fourier Transform Infra Red (IR) Spectroscopy, X-ray diffraction and Scanning Electron Microscope

Cation Exchange Capacity (CEC)
The cation exchange capacity of the modified ion exchange resin was determined by titration method using as ppb, (where, 1 ppb = 1/1000 ppm).Concentrations of the metal ion in solution and that adsorbed on the solid phase are calculated as follows: and the adsorption percentage is given as: Where, q is the amount of the metal adsorbed (mg/g), C o is the initial metal ion concentrations, C aq. is the final aqueous cation concentration (mg/l), V is the solution volume by liter and m is the mass of the metal adsorbent (g).

The Modified Ion Exchange Resin Characterization
The prepared ion exchange resin has the specific surface area 5.2 m 2 /g, hydrogen ion concentrations (pH) is 6.8, the specific density is 1.3 m 3 /g and the specific cation exchange capacities values are 1.1 and 3.0 meq/g, that corresponding to the two functional carboxylic -COOHand -SO 3 H-active groups.
The Infra red absorption bands are given in Figure 3, and their assignment are summarized in Table 1, the results show that strong absorption band appeared at 686 cm -1 , it could be attributed to the bending deformation of SO 2 group.The absorption band was found at 835 cm -1 may be attributed to the multisubstituted benzene ring (C-H group) out of the phase deformation.The strong absorption band appearing at 1423 cm -1 is due to the symmetric stretching vibrations for CH 2 group, other strong absorption band appearing at 1601 cm -1 could be attributed to the symmetric stretching vibration for C = C in benzene ring.The strong absorption band appearing at 1631 cm -1 is due to stretching vibration of the carbonyl group in region of (N -C = O) group.The medium absorption band at 1732 cm -1 is due to stretching vibration of the carbonyl group in free carboxylic group.The broad band appearing at 3300 to 2648 cm -1 is due to the overlap of OH group at the sulphonic and carboxylic acid groups.
X-ray diffraction pattern indicated that the modified ion exchange resin is represented by the major amorphous structure mixed with a small portion of the crystalline structure.The electron microscopy pictures is given in Figures 4 and 5, The Scanning electron microscope of the bulk modified ion exchange resin is given in Figure 4, while Figure 5 gives the sector of this ion exchange resin, the scanning electron microscope are generally used to detect the topography of the resin grain surface and the molecules orientation in the space.From these Figures, it is clear that the prepared ion exchange resin has a micro tubular structure.

Physical and Chemical Parameters
The physical and chemical parameters of the groundwater samples are given in Table 2. Conductivity is the ability of the water to conduct an electrical current, it is directly proportional to the total dissolved solids (TDS) and is an indirect measure of the ion concentration.High concentrations values of the TDS at the groundwater samples No. 5, 6, 8 and 9 indicated by the high salt storage content at these area of the investigated samples These results may also indicated by the releasing of industrial wastes pollution at the area of these samples.The pH varied from 7.5 to 7.6.Concentrations of the major cations, (Na + , K + , Ca 2+ , and Mg 2+ ), and anions (F -, Cl -, 3 HCO  , ) are given in Table 3. Concentrations of the cations and anions in meq/l of the groundwater represented in Figures 6 and 7. Concentrations of the major cationic species are found to decrease   , ▲: . in the following order: Na > Ca > Mg > and K.The major cations species are sodium, and calcium ions species.
these cations may be assumed found as bicarbonates mixed with the minor sulphate ions species.The quality of the water was determined from the charge balance error (%) factor, this factor was calculated from the major cations and anions analyses as follows [11]: The charge balance error (%) =     equivalent of cations equivalent of anions 100 equivalent of cations equivalent of anions If the charge balance calculated value is less than 5%, the quality of the analysis is considered in the acceptable range.these calculations required conversion factor from (mg/l) unit into (meq/l) unit.(Conversion factors from (mg/l) × A = meq/l, where A is the molar volume = 1 charge molecular weight


, this factor depending on the ionic charge and the molecular weight of the ion).The charge balance error factor of the groundwater samples are given between 1.48 % and 4.34 %, which are within of acceptable range.Concentrations of the heavy metals (As, Cd, Co, Cr, Fe, Mn, and Pb,) at the groundwater samples are also given in Table 4, the ions concentrations are compared with the standard guideline values of the world health organization [10].Most of the groundwater samples are found to have a higher concentrations values of , , As, Cd, Co, Pb, Mn and Fe ions species than was reported by the standard guideline limit values of the WHO [10], these results indicated by the releasing of pollutions in the form of bicarbonates, sulphates and/or arsenate ions species

Radiometric Study
Gross alpha and gross beta activity concentrations values at the groundwater samples are summarized in Table 6.
Gross alpha activity values are found between 0.02 and 0.50 Bq/l, these values are lower than the critical detection limit value (0.5 Bq/l) that estimated by the WHO (2004).The groundwater samples have a high gross beta activity concentrations values which are lower than the maximum permitted values (1.0 Bq/l).An increasing in the gross beta activities values at all of the groundwater samples is related to the fact of increasing the natural potassium content at the samples ( 40 K is emitted beta particles).

Speciation of Heavy Metals in the Groundwater
Samples.The groundwater samples (1)(2)(3)(4)(5)(6)(7)(8)(9)(10)(11) are found to contain high concentrations of Pb, Co, Mn and Cd ionic species, concentrations ranges of those elements are compared with the standard guideline of drinking water values.Table 5 gives the heavy metals ranges at the groundwater samples (1-11) and the limit value of the WHO (2004).Most of the groundwater samples contain low concentrations of the gross alpha and beta activity concentrations.Cadmium range 0.01 -0.35 ppm, arsenic from 0.23 to 0.24 mg/l, lead 0.137 -0.295 ppm and cobalt 0.150 -0.93 ppm.Chromium range 0.004 -0.017 mg/l is lower than the permissible limit value 0.10 mg/l.Generally, the increases of heavy metals concentrations in the groundwater might be attributed to the direct input from different sources untreated and treated industrial liquid wastes and dust containing car exhaust, these metals may be diffused from the pollutants to the soil surfaces and water, then it settled in the groundwater resources [11].The species of those ions that dissolved in the groundwater may be expressed as both free and complex compound ions species.Those ions species are calculated at the fixed pH value 7.6 using geochemical code Visual MinteqA2 version 2.3.the minimum and the maximum ions concentrations are used in those calculations are given in Table 5.Table 7 gives the species of the heavy metal ions percentage at the minimum ions concentrations and, Table 8 gives these species at high ions concentrations, from these Tables, it can be stated that:  At the low ions concentrations, low ionic strength, the major of 45.32%     Concentrations of the metal ions are not decreased by the same rate, it depend on many factors such as selectivity and the different in electro-negative charges of the attracting forces between the ions species that dissolved in water and the surface of the solid content of ion exchange resin.The results are with an agreement of other investigations [12,13], many factors are affecting the metal removal percentage by the ion exchange resin, these including:  Competing ions, the removal of heavy metals decreased by increasing of competing ions in the groundwater samples. The ion exchange resin is preferred to the cation has a high valance state, arsenate ions species are completely removed from all groundwater. Among ions having the same charge, sorption process is preferred for the ions have the smallest hydrated diameter such as lead ions Therefore, the removal of heavy metals decreased by the following order: Pb 2+ > Cd 2+ > Co 2+ > Fe 2+ > and Mn 2+ The results are with an agreement of that reported [14].

Conclusions
This research is concerning with the water quality, a modified dioxaloyl-para-sulphanilamide ion exchange resin was prepared in the laboratory is characterized by the, infra red spectra, x-ray diffraction and electronic microscopic, the cation exchange capacity and specific surface area are also performed.Speciation of heavy metals such as; Cr, Cd, Co, As, Mn, Fe and Pb in groundwater samples were performed using visual MinteqA2 geochemical code version 2.3.This modified ion exchange resin was found to be a good adsorbent that used for heavy metal removal from groundwater samples.

Figure 2 .
Figure 2. The dean and stark apparatus.

Scheme 1 .
Scheme 1.The modified ion exchange resin is prepared by the condensation of Dioxalayl-P-Sulphanimide with phenol.

Figure 3 .
Figure 3.The infra red spectra of the modified ion exchange resin.

Figure 4 .
Figure 4. Scanning electron microscope of the bulk modified ion exchange resin.

Figure 5 .
Figure 5. Scanning electron microscope sector of the modified ion exchange resin.

Figure 8 .
Figure 8. Conc. of As, Cd, Cr, Co, Fe, Mn, Pb and V (ppb) ionic species at the groundwater sample No. (11), where is after and is after using the syntheticion exchange material.

Table 1 . The peak assignment for each wave number (cm -1 ) of the IR spectrum at the modified ion exchange resin.
s Symmetric stretching for C = O group in carboxylic group 3300 s Symmetric stretching for OH group in phenolic ring, Sulphonic and carboxylic group