Sepiolite functionalized with N-[3-(trimethoxysilyl)propyl]-ethylenediamine triacetic acid trisodium salt. Part I: Preparation and characterization J. Serb. Chem. Soc. 80 (9) 1193–1202 (2015) UDC 549.623.83.004.12+547.292+ JSCS–4790 546.28–36:543.44–77 Original scientific paper 1193 Sepiolite functionalized with N-[3-(trimethoxysilyl)propyl]- ethylenediamine triacetic acid trisodium salt. Part I: Preparation and characterization SLAVICA S. LAZAREVIĆ*, IVONA M. JANKOVIĆ-ČASTVAN, BOJAN M. JOKIĆ, DJORDJE T. JANAĆKOVIĆ and RADA D. PETROVIĆ Faculty of Technology and Metallurgy, University of Belgrade, Karnegijeva 4, 11000 Belgrade, Serbia (Received 19 February, revised 11 May, accepted 14 May 2015) Abstract: Natural sepiolite from Andrici (Serbia) was functionalized by coval- ent grafting of N-[3-(trimethoxysilyl)propyl]ethylenediamine triacetic acid tri- sodium salt onto the Si–OH sepiolite groups. The functionalized material, MSEAS, was characterized by determination of the phase composition by X- ray diffraction (XRD) analysis, analysis of the morphological characteristics by scanning electron microscopy (SEM), using Fourier transform infrared (FTIR) spectroscopy, differential thermal analyses (DTA), determination of the spe- cific surface areas and pore size distribution using the BET method and point of zero charge (pHpzc) determination. The crystal structure of sepiolite did not change significantly upon surface modification. The FT-IR and DTA analyses confirmed that the modified sample maintained the basic structure of sepiolite and the presence of organic groups in the functionalized sepiolite sample. The point of zero charge of MSEAS in KNO3 solutions of different concentrations, determined by the batch technique, was at pH 7.0±0.1. Keywords: sepiolite; functionalization; N-[3-(trimethoxysilyl)propyl]ethylene- diamine triacetic acid, trisodium salt. INTRODUCTION The variety of possible reactions of the active centres on the surface of clays allows the surface properties to be changed by introduction of new groups of atoms. Grafting is a process that links inorganic and organic components via strong bonds, such as covalent or ionic–covalent linkages, to obtain function- alized clays, i.e., the formation organic–inorganic hybrid materials combining the mechanical stability of a clay framework and the reactivity of organofunctional groups. The alkoxysilane part of an organosilane molecule is capable of bonding * Corresponding author. E-mail: slazarevic@tmf.bg.ac.rs doi: 10.2298/JSC150219038L _________________________________________________________________________________________________________________________ (CC) 2015 SCS. All rights reserved. Available on line at www.shd.org.rs/JSCS/ 1194 LAZAREVIĆ et al. with a variety of mineral or metal surfaces through complex hydrolysis/conden- sation reactions, whereby Si–O–metal bonds are ultimately formed.1 The reactions of clay minerals with reagents containing metal chelating functionalities have recently been explored in an effort to enhance the heavy metal binding capacities of clays and their selectivity to the type of metal con- sidered.2–9 The surface of sepiolite has a great ability for grafting reactions with organo- silanes due to its high content of silanol groups that are very susceptible to the reactions.10 By hydrolysis, the alkoxy-groups of the organosilane (R–SiX3, where X designates hydrolysable alkoxy groups (usually methoxy, –OCH3, or ethoxy, –OC2H5)) are converted to silanol groups, which react with silanol groups of sepiolite forming Si–O–Si covalent bonds.11 The most widely used functional silanes contain thiol (–SH) or amino (–NH2) groups. The surface of sepiolite was previously functionalized using silane coupling agents: 3-mercapto- propyltrimethoxysilane (MPS),2 triethoxy-3-(2-imidazolin-1-yl)propylsilane,12 [3-(2-aminoethylamino)propyl]trimethoxy-silane).13 In previous papers, natural, acid activated and thermo-acid activated sepio- lites were functionalized using (3-mercaptopropyl)trimethoxy-silane and [3-(2- -aminoethylamino)propyl]trimethoxysilane and the capacities of the obtained sorbents for chromium(VI) sorption from aqueous solutions were investi- gated.9,14,15 It was shown that adsorption capacities of the amine-functionalized sepiolites were much higher than those of mercapto-silane functionalized sepio- lites under the same conditions, indicating that adsorption capacities of func- tionalized sepiolites depended on the type of groups covalently grafted to the sepiolite surface. The present study is the first to investigate the modification of sepiolite with N-[3-(trimethoxysilyl)propyl]ethylenediamine triacetic acid trisodium salt in order to improve sorption capacity for metal ions from aqueous solutions. The silanation reagent N-[(3-trimethoxysilyl)propyl]ethylenediamine triacetic acid contains three methoxy groups, which could react with the OH groups on clays, and an EDTA group, which could chelate metals. This paper reports the pre- paration of the modified material and its characterization by XRD analysis, scan- ning electron microscopy (SEM), Fourier transform infrared (FTIR) spectro- scopy, differential thermal analyses (DTA), surface-area analysis and determin- ation of the point of zero charge (pHpzc). In the second part of this paper, the adsorption properties of the functionalized sepiolite sample, the sorption of Ni2+ on the MSEAS as a function of the initial metal concentration, the equilibration time, the pH value and temperature are discussed. _________________________________________________________________________________________________________________________ (CC) 2015 SCS. All rights reserved. Available on line at www.shd.org.rs/JSCS/ PREPARATION AND CHARACTERIZATION OF FUNCTIONALIZED SEPIOLITE 1195 EXPERIMENTAL Materials The natural sepiolite (SEP) used for the modification was obtained from Andrici (Serbia). The chemical composition, specific surface area, pore volume, pore radius, X-ray diffraction, and FTIR analyses of the sample were reported previously.16 The functional- ization of sepiolite was performed from aqueous solution6,17 by mixing a mechanically stirred suspension of 50 g of sepiolite in distilled water, pH of 7.1, with 22.5 mL of a 45 % aqueous solution of N-[3-(trimethoxysilyl)propyl]ethylenediamine triacetic acid trisodium salt ((CH3O)3Si(CH2)3N(CH2COONa)N(CH2)2N(CH2COONa)2), MSEA, Gelest). The mixture was filtered after 2 h and the modified sepiolite sample, MSEAS, was washed with water. Characterization of the modified sepiolite The scanning electron microscopic (SEM) analysis of the sepiolite powder was realized on a Tescan Mira 3 microscope. The powder was fused with a Pd–Pt alloy. X-Ray diffraction (XRD) analysis of the sample was performed using an Ital Structures APD 2000 diffracto- meter with CuKα radiation, in the 2θ angle range from 5 to 60°, with a 0.02° step. Infrared spectroscopy analysis was made on a MB Boman Hartmann 100 instrument in the wave number range from 4000 to 400 cm-1. The sample was prepared by the KBr method at a ratio of sample:KBr of 1:75. Differential thermal analysis in air was realized using an AMINCO instrument with computer-controlled temperature, at a heating rate of 10 °C min-1. The specific surface areas and pore size distribution of the modified sample was esti- mated using nitrogen adsorption–desorption isotherms determined using a Micrometrics ASAP 2020 instrument. Before the sorption measurement, the sample was degassed at 150 °C for 10 h under reduced pressure. The specific surface area of sample (SBET) was calculated according to the Brunauer–Emmett–Teller (BET) method from the linear part of the nitrogen adsorption isotherm.18 The total pore volume (Vtot) was given at p/p0 = 0.998. The volume of the mesopores and pore size distribution were analyzed according to the Barrett, Joyner and Halenda method from the desorption isotherm.19 The volume of the microspores was calcul- ated according to t-plot analysis20 using the Harkins–Jura thickness curve. The point of zero charge (pHpzc) of the modified sepiolite was determined in KNO3 solutions having concentration 0.1, 0.01 and 0.001 mol L-1, using the batch equilibration method as described previously.21 In order to determine the degree of dissolution of the modified sepiolite powder, the concentration of Mg2+ in the solutions after equilibration with a 0.01 mol L-1 KNO3 solution was measured by atomic absorption spectroscopy (AAS, Perkin Elmer 730). RESULTS AND DISCUSSION Characterization of modified sepiolite The characteristic peak positions in the XRD spectrum of the sepiolite sample had not changed after modification with N-[3-(trimethoxysilyl)propyl]- ethylenediamine triacetic acid trisodium salt (Fig. 1), indicating that the structure and crystallinity of sepiolite were maintained, which could be attributed to the functionalization occurring mainly on the surface or by the partial replacement of zeolitic water. _________________________________________________________________________________________________________________________ (CC) 2015 SCS. All rights reserved. Available on line at www.shd.org.rs/JSCS/ 1196 LAZAREVIĆ et al. Fig. 1. XRD spectrum of the MSEAS sample (S – sepiolite). The SEM micrograph of MSEAS is shown in Fig. 2. It could be seen that the modified sepiolite had a fibrous structure, as did the natural sepiolite.22 The mic- rographs of natural sepiolite sample showed the fibres had needle morphology of 30–50 nm in diameter and 1 μm in length. After surface modification, the needle morphology was maintained but with reduced fibre length. The fibres of the func- tionalized sample formed bundle-like aggregates. Fig. 2. SEM micrograph of the modified sepiolite. The FTIR spectrum of the modified sample (Fig. 3) was generally similar to that of natural sepiolite, confirming that the modified material had maintained the basic structure of sepiolite. Three regions indicative for sepiolite23,24 could be observed in Fig. 3: bands in the 4000–3000 cm–1 range corresponding to the vib- rations of the Mg–OH group (3690 cm–1), bound water coordinated to mag- nesium in the octahedral sheet (3570 cm–1) and zeolitic water in the channels (at 3422 cm–1); a band at 1658 cm–1 due to the vibration of zeolitic water; bands in _________________________________________________________________________________________________________________________ (CC) 2015 SCS. All rights reserved. Available on line at www.shd.org.rs/JSCS/ PREPARATION AND CHARACTERIZATION OF FUNCTIONALIZED SEPIOLITE 1197 the 1200–400 cm–1 range characteristic of silicate: bands centred at 1016 and 467 cm–1 due to Si–O–Si vibration; bands at 1215 and 1078 cm–1 due to Si–O bonds; a band at 437 cm–1 originating from octahedral–tetrahedral bonds (Si–O–Mg bonds) and bands at 690 and 637 cm–1 corresponding to vibrations of the Mg–OH bond. The band at 1381 cm–1 corresponds to vibrations of C–H of the CH2 groups. The C–H stretching vibrations of the methoxy (O–CH3) and chain methylene (CH2) groups could be observed at 2850 and 2930 cm–1, respect- ively.9,13 A band, assigned to symmetric COO– stretching vibrations,25 could be clearly observed at 1407 cm–1. The detected CH2 and COOH groups belong to the units of the MSEA, clearly indicating the presence of the organic modifier in the sample. Fig. 3. FT-IR spectrum of the MSEAS sample. The DTA curve of the modified sepiolite, shown in Fig. 4, revealed the decomposition of the aminocarboxylic group on the surfaces of MSEAS and dehydration of the sepiolite structure. The endothermic peak represents the loss Fig. 4. DTA curve of the MSEAS sample. _________________________________________________________________________________________________________________________ (CC) 2015 SCS. All rights reserved. Available on line at www.shd.org.rs/JSCS/ 1198 LAZAREVIĆ et al. of zeolite water (at 150 °C),26 the exothermic peak at 815 °C represents the dehydratation of the octahedrically coordinated hydroxyl groups, i.e., phase transformation of sepiolite into enstatite (MgSiO3). The broad exothermic peak at ≈329 °C reveals the decomposition of the grafted silane ligand and clearly proves the presence of organic silane molecules on the modified material. Textural properties of modified sepiolite Adsorption–desorption isotherms at −196 °C for MSEAS, and the pore volume and pore size distribution are presented in Fig. 5a and b. The MSEAS showsa hysteresis pattern which is associated with the filling and emptying of the mesopores by capillary condensation, but does not show a plateau at high p/p0 values, which is characteristic of a Type IV isotherm. The hysteresis loop is of Type H3. According to the classification of Rouquerol et al.,18 such a shape of a nitrogen Fig. 5. a) Nitrogen adsorption/desorption isotherms; b) pore volume (1) and pore size distribution (2) of the MSEAS. _________________________________________________________________________________________________________________________ (CC) 2015 SCS. All rights reserved. Available on line at www.shd.org.rs/JSCS/ PREPARATION AND CHARACTERIZATION OF FUNCTIONALIZED SEPIOLITE 1199 isotherm is characteristic for Type IIb indicating that the material contained both mesopores, which are responsible for the hysteresis, and macropores, which results in the absence of the plateau typical for mesoporous Type IV isotherms. The H3 hysteresis pattern indicates the presence of slit-like pores.27 From Fig. 5 and the data summarized in Table I (BET surface area, volume of mesopores, Vmesopore, and micropores, Vmicropore, the overall pore volume, Vporetotal, and the maximum, dmax, and average, d, mesopore diameters) and data obtained for a natural sepiolite,16 it could be noticed that the modification of the sepiolite with MSEA caused a small change in the specific surface area, an increase in the total pore volume, the micropore volume and the mesopore volume. Increases in the maximum and average mesopore diameters were obs- erved for the modified sepiolite sample. It could be assumed that silane modi- fication occurred almost exclusively on the external sepiolite surface, with only partial entry into the sepiolite channels, i.e., that the pores of the sepiolite were not closed during the functionalization. TABLE I. The textural properties of the MSEAS SBET / m2 g-1 Vporetotal / cm3 g-1 Vmicropore / cm3 g-1 Vmesopore / cm3 g-1 dmax / nm d / nm 309.9 0.374 0.054 0.325 4.00 6.51 Determination of the point of zero charge of the modified sepiolite The point of zero charge (pHpzc) is an important interfacial parameter, extensively used in characterizing the ionization behaviour of a surface. It is very important for the determination of the acid–base characteristics of the surface functional groups and their interactions with ions from aqueous solutions. The surface potential exists as a direct result of the presence of surface charge. The solution pH value at which the surface charge density of the solid phase is equal to zero (σ0 = 0, ψ0 = 0), is called the point of zero charge (pHpzc). The solid phase surface is positively charged if pH < pHpzc and negatively if pH > pHpzc. The point of zero charge of MSEAS in KNO3 solutions of different con- centrations, determined by the batch technique from the plateaus, i.e., the curve inflexions, from the dependences pHf vs. pHi, (Fig. 6) was at pH 7.0±0.1. The pHpzc determined in KNO3 solutions of different concentrations were inde- pendent of the ionic strength of the KNO3 solutions, indicating that KNO3 was an inert electrolyte, i.e., specific sorption of K+ and NO3– did not occur at the surface. The slight change in the point of zero charge of MSEAS compared with the pHpzc of the natural sepiolite sample (7.4±0.1)16 indicates an insignificant dec- rease in the basicity of the sepiolite surface after functionalization. The dependence of the quantity of Mg2+ released into the solution during equilibration of 0.05 g of the MSEAS with 25 cm3 0.01 mol L–1 KNO3 solution _________________________________________________________________________________________________________________________ (CC) 2015 SCS. All rights reserved. Available on line at www.shd.org.rs/JSCS/ 1200 LAZAREVIĆ et al. is also shown in Fig. 6 in order to determine the degree of dissolution of the modified sepiolite powder. In the investigated pH range, the quantity of Mg2+ present in the solution as a result of the dissolution of sepiolite was almost cons- tant and equal to 0.05 mmol g–1 MSEAS. Fig. 6. a) Determination of the pHpzc of MSEAS in KNO3 solutions of different concentrations; b) dependence of the quantity of Mg2+ released into the solution per unit mass of MSEAS on pHi during equilibration with 0.01 mol L-1 KNO3 solutions. CONCLUSIONS The obtained results showed that natural sepiolite from the Andrici deposit could be modified by treating with N-[3-(trimethoxysilyl)propyl]ethylenediamine triacetic acid trisodium salt in the presence of an aqueous solution. The surface modification of the sepiolite involved chemical reaction of the silanol groups on the sepiolite surface with the alkoxy groups of the organosilane molecule. The signs of modification of the sepiolite surface were: the presence of new exo- thermic peaks in the DTA spectrum for modified sepiolite, the detection of car- boxylic functional groups present on modified sepiolite by FTIR spectroscopy. The point of zero charge of MSEAS in KNO3 solutions of different concentra- tions, determined by the batch technique, was pH 7.0±0.1. Acknowledgements. Financial support through the Ministry of Education, Science and Technological Development of the Republic of Serbia, Project No. III 45019, and FP7 NANOTECH FTM No. 245916 is gratefully acknowledged. _________________________________________________________________________________________________________________________ (CC) 2015 SCS. All rights reserved. Available on line at www.shd.org.rs/JSCS/ PREPARATION AND CHARACTERIZATION OF FUNCTIONALIZED SEPIOLITE 1201 И З В О Д ФУНКЦИОНАЛИЗАЦИЈА СЕПИОЛИТА ПРИМЕНОМ СОЛИ НАТРИЈУМА N-[(3-ТРИМЕТОКСИ)ПРОПИЛ]ЕТИЛЕНДИАМИНТРИАЦЕТАТНЕ КИСЕЛИНЕ. ПРВИ ДЕО: ПРИПРЕМА И КАРАКТЕРИЗАЦИЈА СЛАВИЦА С. ЛАЗАРЕВИЋ, ИВОНА М. ЈАНКОВИЋ-ЧАСТВАН, БОЈАН М. ЈОКИЋ, ЂОРЂЕ Т. ЈАНАЋКОВИЋ и РАДА Д. ПЕТРОВИЋ Технолошко-металуршки факултет Универзитета у Београду, Карнегијева 4, 11000 Београд Природни сепиолит из налазишта Андрићи је функционализован применом соли натријума N-[(3-триметокси)пропил]етилендиаминтриацетатне киселине успоставља- њем ковалентне везе између модификатора и Si–OH површинских група сепиолита. Карактеризација функционализованог узорка означеног са MSEAS извршена је одређи- вањем морфолошких карактеристика применом скенирајуће електронске микроскопије (SEM), одређивањем фазног састава рендгенско-дифракционом анализом (XRD) и при- меном инфрацрвене спектроскопске анализе (FT-IR) и диференцијално-термијске ана- лизе (DTA), као и одређивањем специфичне површине и расподеле величина пора BET методом и тачке нултог наелектрисања (pHpzc). Кристална структура сепиолита није битно промењена поступком функционализације. Резултати FT-IR и DTA анализе потврдили су присуство основне сепиолитске структуре у узорку MSEAS, као и при- суство карбоксилних група органског модификатора. Тачка нултог наелектрисања узорка MSEAS, одређена у растворима KNO3 различитих концентрација применом методе уравнотежавања посебних проба, износи 7,0±0,1. (Примљено 19. фебруара, ревидирано 11. маја, прихваћено 14. маја 2015) REFERENCES 1. Y. Xie, C. A. S. Hill, Z. Xiao, H. Militz, C. 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Available on line at www.shd.org.rs/JSCS/ << /ASCII85EncodePages false /AllowTransparency false /AutoPositionEPSFiles true /AutoRotatePages /None /Binding /Left /CalGrayProfile (Dot Gain 20%) /CalRGBProfile (sRGB IEC61966-2.1) /CalCMYKProfile (U.S. Web Coated \050SWOP\051 v2) /sRGBProfile (sRGB IEC61966-2.1) /CannotEmbedFontPolicy /Error /CompatibilityLevel 1.4 /CompressObjects /Tags /CompressPages true /ConvertImagesToIndexed true /PassThroughJPEGImages true /CreateJobTicket false /DefaultRenderingIntent /Default /DetectBlends true /DetectCurves 0.0000 /ColorConversionStrategy /CMYK /DoThumbnails false /EmbedAllFonts true /EmbedOpenType false /ParseICCProfilesInComments true /EmbedJobOptions true /DSCReportingLevel 0 /EmitDSCWarnings false /EndPage -1 /ImageMemory 1048576 /LockDistillerParams false /MaxSubsetPct 100 /Optimize true /OPM 1 /ParseDSCComments true /ParseDSCCommentsForDocInfo true /PreserveCopyPage true /PreserveDICMYKValues true /PreserveEPSInfo true /PreserveFlatness true /PreserveHalftoneInfo false /PreserveOPIComments true /PreserveOverprintSettings true /StartPage 1 /SubsetFonts true /TransferFunctionInfo /Apply /UCRandBGInfo /Preserve /UsePrologue false /ColorSettingsFile () /AlwaysEmbed [ true ] /NeverEmbed [ true ] /AntiAliasColorImages false /CropColorImages true /ColorImageMinResolution 300 /ColorImageMinResolutionPolicy /OK /DownsampleColorImages true /ColorImageDownsampleType /Bicubic /ColorImageResolution 300 /ColorImageDepth -1 /ColorImageMinDownsampleDepth 1 /ColorImageDownsampleThreshold 1.50000 /EncodeColorImages true /ColorImageFilter /DCTEncode /AutoFilterColorImages true /ColorImageAutoFilterStrategy /JPEG /ColorACSImageDict << /QFactor 0.15 /HSamples [1 1 1 1] /VSamples [1 1 1 1] >> /ColorImageDict << /QFactor 0.15 /HSamples [1 1 1 1] /VSamples [1 1 1 1] >> /JPEG2000ColorACSImageDict << /TileWidth 256 /TileHeight 256 /Quality 30 >> /JPEG2000ColorImageDict << /TileWidth 256 /TileHeight 256 /Quality 30 >> /AntiAliasGrayImages false /CropGrayImages true /GrayImageMinResolution 300 /GrayImageMinResolutionPolicy /OK /DownsampleGrayImages true /GrayImageDownsampleType /Bicubic /GrayImageResolution 300 /GrayImageDepth -1 /GrayImageMinDownsampleDepth 2 /GrayImageDownsampleThreshold 1.50000 /EncodeGrayImages true /GrayImageFilter /DCTEncode /AutoFilterGrayImages true /GrayImageAutoFilterStrategy /JPEG /GrayACSImageDict << /QFactor 0.15 /HSamples [1 1 1 1] /VSamples [1 1 1 1] >> /GrayImageDict << /QFactor 0.15 /HSamples [1 1 1 1] /VSamples [1 1 1 1] >> /JPEG2000GrayACSImageDict << /TileWidth 256 /TileHeight 256 /Quality 30 >> /JPEG2000GrayImageDict << /TileWidth 256 /TileHeight 256 /Quality 30 >> /AntiAliasMonoImages false /CropMonoImages true /MonoImageMinResolution 1200 /MonoImageMinResolutionPolicy /OK /DownsampleMonoImages true /MonoImageDownsampleType /Bicubic /MonoImageResolution 1200 /MonoImageDepth -1 /MonoImageDownsampleThreshold 1.50000 /EncodeMonoImages true /MonoImageFilter /CCITTFaxEncode /MonoImageDict << /K -1 >> /AllowPSXObjects false /CheckCompliance [ /None ] /PDFX1aCheck false /PDFX3Check false /PDFXCompliantPDFOnly false /PDFXNoTrimBoxError true /PDFXTrimBoxToMediaBoxOffset [ 0.00000 0.00000 0.00000 0.00000 ] /PDFXSetBleedBoxToMediaBox true /PDFXBleedBoxToTrimBoxOffset [ 0.00000 0.00000 0.00000 0.00000 ] /PDFXOutputIntentProfile () /PDFXOutputConditionIdentifier () /PDFXOutputCondition () /PDFXRegistryName () /PDFXTrapped /False /CreateJDFFile false /Description << /ARA /BGR /CHS /CHT /CZE /DAN /DEU /ESP /ETI /FRA /GRE /HEB /HRV (Za stvaranje Adobe PDF dokumenata najpogodnijih za visokokvalitetni ispis prije tiskanja koristite ove postavke. Stvoreni PDF dokumenti mogu se otvoriti Acrobat i Adobe Reader 5.0 i kasnijim verzijama.) /HUN /ITA /JPN /KOR /LTH /LVI /NLD (Gebruik deze instellingen om Adobe PDF-documenten te maken die zijn geoptimaliseerd voor prepress-afdrukken van hoge kwaliteit. De gemaakte PDF-documenten kunnen worden geopend met Acrobat en Adobe Reader 5.0 en hoger.) /NOR /POL /PTB /RUM /RUS /SKY /SLV /SUO /SVE /TUR /UKR /ENU (Use these settings to create Adobe PDF documents best suited for high-quality prepress printing. Created PDF documents can be opened with Acrobat and Adobe Reader 5.0 and later.) >> /Namespace [ (Adobe) (Common) (1.0) ] /OtherNamespaces [ << /AsReaderSpreads false /CropImagesToFrames true /ErrorControl /WarnAndContinue /FlattenerIgnoreSpreadOverrides false /IncludeGuidesGrids false /IncludeNonPrinting false /IncludeSlug false /Namespace [ (Adobe) (InDesign) (4.0) ] /OmitPlacedBitmaps false /OmitPlacedEPS false /OmitPlacedPDF false /SimulateOverprint /Legacy >> << /AddBleedMarks false /AddColorBars false /AddCropMarks false /AddPageInfo false /AddRegMarks false /ConvertColors /ConvertToCMYK /DestinationProfileName () /DestinationProfileSelector /DocumentCMYK /Downsample16BitImages true /FlattenerPreset << /PresetSelector /MediumResolution >> /FormElements false /GenerateStructure false /IncludeBookmarks false /IncludeHyperlinks false /IncludeInteractive false /IncludeLayers false /IncludeProfiles false /MultimediaHandling /UseObjectSettings /Namespace [ (Adobe) (CreativeSuite) (2.0) ] /PDFXOutputIntentProfileSelector /DocumentCMYK /PreserveEditing true /UntaggedCMYKHandling /LeaveUntagged /UntaggedRGBHandling /UseDocumentProfile /UseDocumentBleed false >> ] >> setdistillerparams << /HWResolution [2400 2400] /PageSize [612.000 792.000] >> setpagedevice