Spiritual

Sorption of organic compounds from aqueous solutions by glycidyl methacrylate-styrene-ethylene dimethacrylate terpolymers

Description
Sorption of organic compounds from aqueous solutions by glycidyl methacrylate-styrene-ethylene dimethacrylate terpolymers
Categories
Published
of 14
All materials on our website are shared by users. If you have any questions about copyright issues, please report us to resolve them. We are always happy to assist you.
Related Documents
Share
Transcript
  REACTIVE FUNCTIONAL POLYMERS Reactive & Functional Polymers 33 (1997) 275-288 Sorption of organic compounds from aqueous solutions by glycidyl methacrylate-styrene-ethylene dimethacrylate terpolymers Valentina V. Podlesnyuk a, JiZ Hradil b,*, Ruslan M. Marutovskii a, Natalia A. Klimenko a, Lev E. Fridman a a zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA nstitute of Colloid Chemistry and Chemistry of Water; Ukrainian Academy of Sciences Vernadskii px 42 Kiev 142 Ukraine b Institute of Macromolecular Chemistry Academy of Sciences of the Czech Republic Heyrovskj Sq. 2 162 06 Prague 6 Czech Republic Received 10 July 1996; accepted 28 December 1996 bstract A series of macroporous methacrylate sorbents with different chemical structure and polarity was prepared to examine the effect of polarity on the sorption of organic compounds from aqueous solutions. A method was proposed for simultaneous determination of the parameters of the Aranovich isotherm on the basis of the experimental values describing the sorption equilibria. The results obtained for the sorption of a number of organic compounds on glycidyl methacrylate- styrene-ethylene dimethacrylate terpolymers were analyzed from the point of view of their sorption mechanisms. Keywords: Macroporous methacrylate sorbents; 2,3-Epoxypropyl methacrylate-styrene-ethylene dimethacrylate terpoly- mers; Sorption of organic compounds from aqueous solutions - zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFE 1 Introduction In the last two decades we have seen major progress in the field of sorption from solutions both in experimental work and in its theoreti- cal understanding as can be seen from work of many research groups [ 1,2]. In addition to tra- ditional carbon and inorganic sorbents, organic compounds can also be sorbed from water using porous polymer sorbents [3-91. The factors that make the use of macroporous copolymers advan- tageous for the sorption of organic compounds from water are as follows. The partition coeffi- cients of compounds in a polymer-water system tend to infinity if the polymer is selected correctly * Corresponding author. for the type of contaminants present. Sorption of water on the hydrophobic copolymers is very low usually, from the columns packed with styrene- divinylbenzene polymers water is eluted close to propane [lo]. Polymeric sorbent can be produced in the form of regular beads of required size. Also the flow resistance of columns packed with bead sorbent is lower, enabling work to be performed at a smaller pressure drop. The polymer sorbents can differ in the con- tents of monomer and crosslinking agent, and in the synthesis and polymerization conditions [ 1 I]. Copolymers of styrene and divinylben- zene are typical nonpolar sorbents. Polar poly- mer sorbents are formed by copolymerization of polar monomers, such as acrylonitrile [12], vinylpyridine [ 131 and various methacrylate com- 1381-.5148/97/ 17.00 1997 Elsevier Science B.V. All rights reserved. PZI S1381-5148(97)00065-5  276 VII Podlesnyuk et al. /Reactive & Functional Polymers 33 (1997) 275-288 pounds [14,15] with divinylbenzene or ethy- lene dimethacrylate. In general, hydrophobic molecules are attracted from aqueous solutions by the hydrophobic polymer surface of the sorbent and hydrophilic molecules, by the hy- drophilic surface. Capacity factors, k’, (ratio of the retention vol- ume of solute sorbed on the resin and the solute present in the void volume of the column) show [16] that Amberlite XAD-8 resin apparently favours aliphatic over aromatic and alicyclic car- bon systems. For aromatic, aliphatic, and ali- cyclic organic solutes with functional groups, the order of preference is: -CH3 > -C02H > -CHO > -OH > -NH2 In both cases the order follows the inverse solubility trend. If the logarithm of the aqueous molar solubility, c,, is plotted against logk’, a well defined linear relationship results with a correlation coefficient of 0.9. The equation is: log k’ = 1.77 - 0.52 log cs Other nonionic Amberlite XAD resins (XAD-1, -2, -4 and -7) show similar relationships. Previously, glycidyl methacrylate-ethylene dimethacrylate copolymers showed [ 171, that particularly in the case of polymers crosslinked to a lower degree and having as a consequence, smaller inner surface, organic compounds dis- solve in the polymer bulk. The sorption properties of a series of styrene- acrylonitrile divinylbenzene terpolymers with re- spect to phenol, p-nitrophenol and p-nitroaniline, seem to be independent of the sorbent compo- sition [ 181. According to Kolarz and coworkers [ 181, the sorption degree of phenols and ani- lines in the case of acrylonitrile-divinylbenzene copolymers depends more on the surface polarity than on its specific surface area. The extent of sorption also varies with the chemical structure of the sorbed compounds. The variation of the distribution coefficient of substituted phenols in styrene-divinylbenzene and acrylonitrile-divinylbenzene copolymers has been described in terms of the Hammett equation, using the n-constants, which predominantly in- clude the inductive effect of the substituent on sorption [19,20]. For both the sorbents nitrophe- no1 isomers are sorbed in the following order [2 zyxwvutsr  ] : ortho > para > meta The role of simple models and elementary thermodynamic and statistical mechanical argu- ments was first discussed in relation to the con- cept of a ‘surface phase’. According to Everett [2], the monolayer models of the sorption region are often inadequate and thicker surfaces have to be assumed. A sharp boundary between surface and bulk phases is thermodynamically unaccept- able and it is necessary to develop a multilayer model and extend it to mixtures of molecules of different size. Theories of dual-mode penetrant transport in amorphous polymers were derived by Paul and Koros [22]. Therefore, the Aranovich equation for the de- scription of the sorption isotherms of swollen sorbent [23] was used in the calculation of the sorption equilibria on nonpolar polymer sorbents. These relationships do not generalize the ap- proach for polymer sorbents with swelling poly- mer matrices. Previously, we studied the effect of the monomer and crosslinking agent contents of glycidyl metbacrylate-ethylene dimethacrylate (GMA-EDMA) copolymers on their sorption activity [24,25]. This paper describes the ef- fect of changes in the chemical composition of the glycidyl methacrylate-styrene-ethylene dimethacrylate (GMA-ST-EDMA) terpolymer on their sorption properties. 2. Experimental 2 1 Materials Copolymers of the general formula shown in Scheme 1 were synthesized. Terpolymers containing up to 50 wt styrene were prepared by suspension radical polymer- ization. In a mixture containing 96 g (0.484 mol) EDMA, 144 g GMA+ST (1.013-0.169  VI? Podlesnyuk et al. /Reactive & Functional Polymers 33 (1997) 275-288 211 Table 1 Properties of GMA-ST-EDMA terpolymers Polymer G60 GS55-5 GS50-10 GS30-30 GSlO-50 S60 C Styrene a s&T b (%I (wt%) (m’/g) 59.38 0 51.0 51.12 5.7 55.9 62.71 13.1 53.2 68.92 46.8 50.7 75.80 64.8 49.8 78.44 71.1 60.3 “gC Pd (dg) * (Wg) g (%I’ (%I* 1.50 1.31 66.2 63.0 1.39 1.37 64.4 64.1 1.30 1.21 62.9 61.1 1.11 1.24 59.2 61.7 0.19 1.53 _ 66.5 0.14 1.62 _ 67.8 re (Wf bMg 59.0 51.3 49.8 49.1 49.0 45.4 44.0 48.9 - 61.4 _ 53.8 a Styrene content calculated from the elemental analysis data. b Specific surface determined from the desorption of nitrogen. ’ Specific pore volume. d Porosity p = 100Vs/[Vg + (l/d)], where d is the polymer density. e Mean pore radius calculated from the relationship r = 2000Vg/Sg. *According to the water regain. s According to the cyclohexane regain. mol GMA and 0.0-1.152 mol ST), 327.6 g cy- clohexanol and 32.4 g dodecanol, 2.4 g initia- tor azobisisobutyronitrile (AIBN) was dissolved. The aqueous dispersion phase (1800 ml), consist- ing of 1 solution of polyvinylpyrrolidone (MW 360000), was introduced into a reactor (Buchi, Switzerland), 3 1 in volume, provided with an an- chor stirrer and heating jacket with water as the heating medium, and was mixed there with the organic phase. Nitrogen was passed through the mixture for 10 min. The reactor was then closed. The mixture was stirred (150 rpm) at room tem- perature for 30 min, then at 70°C for 8 h. When the contents of the reactor had cooled, the par- ticles were separated on a glass filter. The sus- pension stabilizer which adhered to their surface CH3 -+H,- CH3 . . . . . -~H-CHz- . . . . . -d-CH,- CHXO CH; CH, 6 C-0 -&-CH2- kH, GMA ST Scheme 1. zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA EDMA was removed by decantation, and the particles were washed with ethanol and dried in vacua at a temperature below 50°C. Sieve fractionation yielded particle fractions having the respective size ranges 250-400 ,um (‘fine’) and 500-800 pm (‘coarse’) used in the sorption measurement. The following synthesized polymers were used as sorbents: G60, copolymer of GMA with 40 wt EDMA. GS, GMA-ST-EDMA terpolymers which al- ways contain 40 wt EDMA. (The numbers de- Table 2 Properties of organic substances used as sorbates Sorbate c, a db MW= Pd (mmoVg) (g/ml) (A*) Catechol 3905.2 1.371 110.11 28.4 Phenol 925 1.071 94.11 30.2 Aniline 388 1.022 93.12 31.0 3-Aminophenol 238.5 1.328 109.12 28.9 3,4,5-Trihydroxy- 68.2 1.694 188.13 35.4 benzoic acid 3-Aminobenzoic acid 43.75 1.511 137.14 30.9 2-Aminobenzoic acid 33 1.412 137.14 32.3 4-Chloroaniline 24 1.427 127.57 30.6 Benzoic acid 17.2 1.266 122.12 28.2 Benzene 10.5 0.879 78.11 30.5 a Solubility. b Density. ’ Molecular weight. d Surface occupied by one molecule of sorbate, calculated ac- cording to Eq. 5.  278 KC Podlesnyuk t al. Reactive & Functional Polymers 33 (1997) 275-288 zyxwvutsrqponmlkjihgfedcbaZYX Table 3 Experimental values of sorption of sorbates from water on GMA-ST-EDMA copolymers Sorbate G60 GS55-5 c (mmol/l) a OnmoW c (mmol/l) a @moW GS50-10 c (mmoy1) a @moW Phenol 1.00 0.085 0.60 2.00 0.150 1.50 4.00 0.230 3.10 6.20 0.275 4.60 7.80 0.340 7.10 0.95 0.14 0.80 2.00 0.23 1.90 4.80 0.40 4.60 7.30 0.50 7.50 11.2 0.62 9.80 14.6 0.71 14.1 3-Aminophenol 2.00 0.125 2.00 4.20 0.230 4.50 6.30 0.310 7.60 8.60 0.380 9.40 11.4 0.470 11.8 3,4,5-Trihydroxybenzoic acid 0.45 0.024 0.45 0.80 0.038 1.10 1.35 0.058 1.90 2.10 0.084 2.60 2.95 0.111 3.30 4.20 0.143 4.05 3-Aminobenzoic acid - 1.05 2.05 3.00 3.90 4.80 0.60 zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA  24 0.70 0.28 1.40 0.40 1.75 0.50 3.15 0.65 3.10 0.68 5.30 0.90 4.50 0.86 7.15 1.07 6.35 1.02 8.40 1.17 Catechol - 2.80 0.155 6.00 0.265 7.50 0.290 10.0 0.350 13.9 0.370 17.3 0.430 0.065 0.125 0.119 0.255 0.325 0.14 0.26 0.45 0.58 0.67 0.81 0.100 0.205 0.300 0.350 0.410 0.020 0.043 0.070 0.920 1.110 1.400 0.045 0.095 0.130 0.168 0.205 2-Aminobenzoic acid Benzoic acid 1.20 0.17 1.10 2.50 0.31 2.30 5.30 0.50 5.20 8.70 0.57 8.50 15.6 0.60 15.5 0.80 0.070 0.35 1.50 0.150 0.70 3.20 0.260 1.30 5.00 0.340 2.90 7.05 0.380 4.60 9.10 0.395 6.50 - 8.50 - 11.4 0.50 0.040 0.45 1.65 0.105 1.02 2.95 0.170 2.40 4.25 0.220 3.55 5.20 0.245 4.90 0.22 1.00 0.24 0.38 2.30 0.40 0.55 5.20 0.59 0.61 8.50 0.66 0.65 15.3 0.72 0.05 0.09 0.19 0.35 0.45 0.52 0.56 0.58 0.065 0.30 0.08 0.120 1.10 0.15 0.190 2.05 0.22 0.250 3.10 0.28 n 365 4.45 0.36 0.45 0.26 1.15 0.45 2.90 0.62 5.15 0.96 6.85 1.13 9.05 1.27 0.90 0.070 1.90 0.120 3.30 0.175 6.20 0.275 6.20 0.275 0.90 0.13 2.20 0.25 5.10 0.25 8.00 0.52 11.8 0.63 15.2 0.73 2.10 0.105 4.30 0.200 7.50 0.295 10.4 0.375 11.9 0.405 0.40 0.016 0.95 0.032 1.65 0.054 2.55 0.078 3.60 0.120 4.70 0.26 - - 0.30 0.06 1.25 0.23 2.90 0.38 4.50 0.47 6.35 0.54 8.30 0.58  K x Podlesnyuk et al. /Reactive & Functional Polymers 33 (1997) 275-288 279 zyxwvutsr Table 3 (continued) Sorbate GS30-30 c (mmol/l) a (mmolk) GSlO-50 c (mmovl) a (molk) S60 c (mmolil) a WW Catechol 2.60 0.17 1.80 0.09 6.20 0.25 2.90 0.18 8.60 0.34 6.10 0.28 12.6 0.36 11.3 0.36 17.2 0.42 15.9 0.42 4-Chloroaniline 0.35 0.28 0.95 0.48 2.65 0.77 5.00 1.04 6.0 1.18 _ 0.30 0.30 0.90 0.50 2.50 0.80 4.85 1.08 6.25 1.23 8.30 1.42 3-Aminophenol 3,4,5-Trihydroxybenzoic acid 3-Aminobenzoic acid 2-Aminobenzoic acid Benzoic acid Benzene 2.20 0.100 2.30 0.085 4.60 0.180 4.70 0.150 6.90 0.240 7.70 0.205 9.80 0.310 10.5 0.255 12.4 0.375 12.8 0.290 0.47 0.015 0.55 0.012 1.15 0.036 1.25 0.024 1.85 0.048 2.35 0.040 2.75 0.064 3.55 0.054 3.75 0.078 4.85 0.063 0.85 0.016 1.75 0.078 2.40 0.105 3.65 0.158 4.70 0.200 0.90 0.25 0.80 0.27 2.10 0.41 1.90 0.43 4.80 0.62 4.40 0.65 8.40 0.71 7.70 0.74 15.0 0.79 14.4 0.85 0.30 0.07 1.25 0.29 2.15 0.50 4.40 0.65 6.60 0.75 8.80 0.80 11.60 0.91 0.20 0.10 0.50 0.18 1.10 0.32 2.50 0.56 4.20 0.72 6.10 0.80 7.90 0.89 10.2 1.00 0.25 0.60 1.25 2.10 3.40 0.10 0.19 0.29 0.39 0.48 0.55 0.20 0.14 0.50 0.30 1.10 0.46 2.35 0.60 3.90 0.69 1.00 0.12 2.20 0.23 5.10 0.39 8.30 0.50 11.7 0.59 15.0 0.68 0.30 0.34 1.00 0.57 2.75 0.86 5.00 1.14 6.80 1.33 8.85 1.53 - 0.35 0.16 0.70 0.33 2.20 0.59 4.80 0.88 6.70 1.03 10.5 1.24 4.75
Search
Tags
Related Search
We Need Your Support
Thank you for visiting our website and your interest in our free products and services. We are nonprofit website to share and download documents. To the running of this website, we need your help to support us.

Thanks to everyone for your continued support.

No, Thanks
SAVE OUR EARTH

We need your sign to support Project to invent "SMART AND CONTROLLABLE REFLECTIVE BALLOONS" to cover the Sun and Save Our Earth.

More details...

Sign Now!

We are very appreciated for your Prompt Action!

x