Development of an Adsorption Process for the Removal of Pharmaceuticals from Wastewater Treatment Plant Effluents by Means of Molecularly Imprinted Polymers and Commercial Adsorbents

Metadata of the chapter that will be visualized in SpringerLink Book Title Resource Recovery from wastewater treatment Series Title Chapter Title Development of an Adsorption Process for the Removal of Pharmaceuticals from Wastewater Treatment Plant Effluents by Means of Molecularly Imprinted Polymers and Commercial Adsorbents Copyright Year 2024 Copyright HolderName The Author(s), under exclusive license to Springer Nature Switzerland AG Corresponding Author Family Name Girometti Particle Given Name Elisa Prefix Suffix Role Division Department of Civil, Chemical, Environmental and Materials Engineering Organization University of Bologna Address Bologna, Italy Email [email protected] Author Family Name Maggetti Particle Given Name Carla Prefix Suffix Role Division Department of Civil, Chemical, Environmental and Materials Engineering Organization University of Bologna Address Bologna, Italy Email Author Family Name Frascari Particle Given Name Dario Prefix Suffix Role Division Department of Civil, Chemical, Environmental and Materials Engineering Organization University of Bologna Address Bologna, Italy Email Author Family Name Pinelli Particle Given Name Davide Prefix Suffix Role Division Department of Civil, Chemical, Environmental and Materials Engineering Organization University of Bologna Address Bologna, Italy Email Author Family Name Sisti Particle Given Name Laura Prefix Suffix Role Division Department of Civil, Chemical, Environmental and Materials Engineering Organization University of Bologna Address Bologna, Italy Email Author Family Name Savigni Particle Given Name Elettra Prefix Suffix Role Division Department of Civil, Chemical, Environmental and Materials Engineering Organization University of Bologna Address Bologna, Italy Email Abstract Pharmaceuticals are micropollutants that represent a worldwide threat as they are continuously detected in the aquatic environment. Wastewater treatment plant effluents are one of the major sources of pharmaceuticals in aquatic environments, as conventional wastewater treatment is not able to efficiently remove them. Among the most concerning pharmaceuticals, diclofenac and carbamazepine are widely detected in waters; for this reason, they were chosen as target compounds for this work. Molecularly Imprinted Polymers were designed and prepared for selective removal of diclofenac and carbamazepine and their adsorption performances from real effluents were compared with those of commercial materials, such as activated carbon Norit and Amberlite XAD16N. Some Molecularly Imprinted Polymers showed promising adsorption performances in batch adsorption tests in comparison with tested commercial materials. The real effectiveness of best MIPs will be further tested in a packed bed column to develop a cost-effective adsorption/desorption process. Keywords (separated by '-') Molecularly Imprinted Polymers - wastewater treatment - carbamazepine - diclofenac - pharmaceuticals Development of an Adsorption Process for the Removal of Pharmaceuticals from Wastewater Treatment Plant Effluents by Means of Molecularly Imprinted Polymers and Commercial Adsorbents Elisa Girometti(B), Carla Maggetti, Dario Frascari, Davide Pinelli, Laura Sisti, and Elettra Savigni Department of Civil, Chemical, Environmental and Materials Engineering, University of Bologna, Bologna, Italy [email protected] Abstract. Pharmaceuticals are micropollutants that represent a worldwide threat as they are continuously detected in the aquatic environment. Wastewater treatAQ1 ment plant effluents are one of the major sources of pharmaceuticals in aquatic environments, as conventional wastewater treatment is not able to efficiently remove them. Among the most concerning pharmaceuticals, diclofenac and carbamazepine are widely detected in waters; for this reason, they were chosen as target compounds for this work. Molecularly Imprinted Polymers were designed and prepared for selective removal of diclofenac and carbamazepine and their adsorption performances from real effluents were compared with those of commercial materials, such as activated carbon Norit and Amberlite XAD16N. Some Molecularly Imprinted Polymers showed promising adsorption performances in batch adsorption tests in comparison with tested commercial materials. The real effectiveness of best MIPs will be further tested in a packed bed column to develop a cost-effective adsorption/desorption process. Keywords: Molecularly Imprinted Polymers ·wastewater treatment · carbamazepine ·diclofenac ·pharmaceuticals 1 Introduction The presence of pharmaceuticals in the aquatic environment even at very low concentrations can lead to uncertain toxic effects on both human beings and aquatic ecosystems, hence the importance of a global worldwide collaboration to obtain the monitoring data that will help to make decision to reduce the environmental impacts of pharmaceuticals (Wilkinson et al., 2022). The concern about these micropollutants and their potential toxicity is increasing, as proved by the draft of the new EU wastewater directive, which requires an average 80% removal of at least 6 pharmaceuticals. Carbamazepine and diclofenac, widely detected in water bodies, were chosen as target compounds in this © The Author(s), under exclusive license to Springer Nature Switzerland AG 2024 G. Mannina et al. (Eds.): ICWRR 2024, LNCE 524, pp. 1–6, 2024. https://doi.org/10.1007/978-3-031-63353-9_46 Author Proof 2 E. Girometti et al. work. Carbamazepine (CBZ) is an anticonvulsant and analgesic drug used to control seizures and to treat pain resulting from trigeminal neuralgia. Diclofenac (DCF) belongs to the category of Non-Steroidal Anti-inflammatory Drugs (NSAIDs), and it is one of the most used analgesic, antipyretic and anti-inflammatory drugs. Both are poorly removed by conventional wastewater treatment plants (WWTPs). The main treatments that can be employed to remove pharmaceuticals removal are classified as physical (adsorption, membranes) and chemical (advanced oxidation processes like ozonation, UV/H2O2, O3/H2O2) (Loganathan et al., 2023). This work investigates pharmaceutical removal by adsorption, in consideration of its low capital investment, applicability at low concentrations and absence of production of toxic byproducts. Molecularly Imprinted Polymers (MIPs) were developed and tested to find non-conventional materials as valid alternatives to commercial adsorbent like activated carbon that are widely used for its effectiveness and flexibility (Gutiérrez et al., 2023). MIPs, produced by radical polymerization, are characterized by highly selective sites with specific affinity for the target molecule for which they are developed, high mechanical and chemical resistance and the possibility of being regenerated multiple times (Parlapiano et al., 2021).Thelatterisaverysignificant aspect to consider for application in a packed bed column, as desorption from activated carbon is expensive and usually performed off-site. 2 Materials and Methods 2.1 Adsorbent Materials The tested commercial adsorbent materials are Amberlite XAD16N, a non-ionic styrenedivinylbenzene adsorption solid phase, and activated carbon Norit GAC 1240 W. MIPs were synthetized by bulk polymerization according to the following procedure proposed by (Cantarella et al., 2019): 0.2 mmol of template (target pharmaceutical), 2 mmol of monomer and 8 mL of porogen (acetonitrile), were mixed in a threenecked flask for 15–20 min (pre-polymerization step) then, 10 mmol of cross-linker and 5.1 mmol of initiator (AIBN) were added and the mixture was degassed with a nitrogen flow for 5 min and then sealed and placed in a silicon oil bath at 70 °C for 4 h. 10 different MIPs were produced for each pharmaceutical by combining 5 monomers with 2 crosslinkers. Each MIP was labelled with the acronym MIP_J_X_Y_Z, where: J indicates the target pharmaceutical (CBZ or DCF), X indicates the monomer (methacrylic acid (MAA), 2-vinylpyridine (2VP), 2-hydroxyethyl methacrylate (HEMA), methacrylamide (MAAM), or itaconic acid (ITA)), Y indicates the cross-linker (a difunctional one that is ethylene glycol methacrylate (EG), and a trifunctional one that is trimethylolpropane triacrylate (TRIM)), and Z indicates the template removal procedure (L1: washing the polymer with a Buchner by a continuous flow of 200 mL of methanol and acetic acid 9:1 v/v; L2: putting the polymer under agitation in 50 mL of methanol and acetic acid 9:1 v/v for 30 min at 30 °C and refreshing the solvent for 3 times). 2.2 Analytical Methods for Carbamazepine and Diclofenac Quantification CBZ and DCF content was determined by using a Waters UPLC-MS (for low concentrations in real wastewater) and a UV-vis spectrophotometer (for high concentrations in Author Proof Development of an Adsorption Process 3 both synthetic solution and spiked real wastewater). The UPLC-MS method employs an Acquity UPLC BEH C18 column, a mobile phase composed of 60:40 water:acetonitrile (v/v) and 0.1% of formic acid and a flow rate of 0.4 mL/min. As far as UV-Vis absorption is concerned, the absorption peak of CBZ was read at 279 nm and that of DCF was read at 269 nm. 2.3 Adsorption Isotherms The batch isotherm tests were performed in both deionized water synthetic solutions and in real WWTP effluent for CBZ and just in WWTP effluent for DCF: for all the tests, the starting concentrations were in the range 0.5–12 mg/L, the concentration of the adsorbent material was 1 gadsorbent/L, the temperature of the rotary shaker was set at 22 °C and the rotational speed was set at 160 rpm. 3 Results and Discussion 3.1 Adsorption Isotherms of Carbamazepine in Deionized Water and Real WWTP Effluent The adsorption isotherms obtained for CBZ in deionized water are reported in Fig. 1. It is possible to observe that Norit outperformed all the other materials, MIPs with EG performed worse than MIP with TRIM and that all the MIPs with TRIM showed similar performances. For CBZ in real WWTP effluent, all the adsorption isotherms obtained are reported in Fig. 2. In this case, the best materials are XAD16N, Norit and MIP_CBZ_MAA_TRIM_L2. As in deionized water, MIPs with EG performed worse than MIPs with TRIM. Among MIPs with trifunctional cross-linker and template removal method L1, the best monomers seem to be HEMA, MAA and 2VP. The template removal method L2 seems to have improved the performance of MIP_CBZ_MAA_TRIM and decreased the performance of MIP_CBZ_HEMA_TRIM while for MIP_CBZ_ 2VP_TRIM the performance is similar. 3.2 Adsorption Isotherms of Diclofenac in Real WWTP Effluent The adsorption isotherms obtained for DCF in WWTP effluent are reported in Fig. 3together with the best fitting Langmuir simulations for XAD16N, Norit and MIP_DCF_2VP_EG_L1. The corresponding Langmuir parameters are reported in Table 1. The best materials resulted to be Norit, XAD16N and MIP_DCF_2VP_TRIM_L1. As for CBZ, also for DCF MIPs produced with EG performed worse than MIPs with TRIM. Author Proof 4 E. Girometti et al. Fig. 1. Adsorption isotherms for CBZ in deionized water Fig. 2. Adsorption isotherms for CBZ in real WWTP effluent Author Proof Development of an Adsorption Process 5 Fig. 3. Adsorption isotherms for DCF in real WWTP effluent Table 1. Langmuir best fit parameters for isotherms conducted with XAD16N, Norit and MIP_DCF_2VP_EG_L1 Langmuir parameters units XAD16N Norit GAC MIP_DCF_2VP_EG_L1 c∞ smgdcf/gdrymaterial 8.9 12.5 7.2 Keq Lmg −11.16 2.1 0.37 R2–0.98 0.9 0.74 4 Conclusions This work showed the effectiveness of Norit GAC 1240 W in removing both carbamazepine and diclofenac from real WWTP effluent; indeed, activated carbon is the most widely used material in several large-scale WWTPs (Benstoem et al., 2017). Commercial resin XAD16N and some MIPs demonstrated promising performances in removing both target pharmaceuticals. Breakthrough tests with a special focus on the desorption phase are in progress with the best materials, aiming at developing a selective and cost-effective adsorption process. AQ2 Funding. This work received funding from the European Union’s Horizon Europe research and innovation program under grant agreements No. 101082048 (MAR2PROTECT project). References Benstoem, F., et al.: Performance of granular activated carbon to remove micropollutants from municipal wastewater—a meta-analysis of pilotand large-scale studies. Chemosphere 185, 105–118 (2017). https://doi.org/10.1016/j.chemosphere.2017.06.118 Author Proof 6 E. Girometti et al. Cantarella, M., et al.: Molecularly imprinted polymer for selective adsorption of diclofenac from contaminated water. Chem. Eng. J. 367, 180–188 (2019). https://doi.org/10.1016/j.cej.2019. 02.146 Gutiérrez, M., Verlicchi, P., Mutavdži´c Pavlovi´c, D.: Study of the influence of the wastewater matrix in the adsorption of three pharmaceuticals by powdered activated carbon. Molecules 28, 2098 (2023). https://doi.org/10.3390/molecules28052098 Loganathan, P., Vigneswaran, S., Kandasamy, J., Cuprys, A.K., Maletskyi, Z., Ratnaweera, H.: Treatment trends and combined methods in removing pharmaceuticals and personal care products from wastewater—a review. Membranes 13, 158 (2023). https://doi.org/10.3390/membra nes13020158 Parlapiano, M., et al.: Selective removal of contaminants of emerging concern (CECs) from urban water cycle via Molecularly Imprinted Polymers (MIPs): potential of upscaling and enabling reclaimed water reuse. J. Environ. Chem. Eng. 9, 105051 (2021). https://doi.org/10.1016/j. jece.2021.105051 Wilkinson, J.L., et al.: Pharmaceutical pollution of the world’s rivers. Proc. Natl. Acad. Sci. U.S.A. 119, e2113947119 (2022). https://doi.org/10.1073/pnas.2113947119 Author Proof Author Queries Chapter 46 Query Refs. Details Required Author’s response AQ1 This is to inform you that corresponding author has been identified as per the information available in the Copyright form. AQ2 Kindly note that the sentence starts with This work received funding from the European... have been treated as Acknowledgment. Please check and confirm. Author Proof