Rejection of trace pharmaceutically active compounds present in municipal wastewaters using ceramic fine ultrafiltration membranes: Effect of feed solution pH and fouling phenomena

[EN] This study investigates the influence of feed solution pH and fouling on the rejection of ten selected pharmaceutically active compounds (PhACs) with different physicochemical characteristics (molecular weight, water solubility, log Kow, pKa, dipole moment, etc.) by three multichannel ceramic ultrafiltration membranes, ranging from 1 to 8 kDa, in order to improve their removal from water. For this purpose, the comparison between filtration of PhACs in deionised water (Feed I) and in real wastewater effluent (Feed II) was performed, demonstrating that the variation of pH and the formation of a foulant layer altered the separation mechanism and hence the rejection values of each PhAC varied. Higher rejections of most of the PhACs were higher at slightly alkaline pH, especially for anionic compounds in the filtration with real wastewater. In these conditions, flux decline was more severe. The formed fouling layer onto the hydrophilic membrane surface acted as a secondary barrier for separation with different properties like hydrophobicity and charge. Electrostatic interactions were the main separation mechanism in the filtration of PhACs in deionised water, while the hydrophobic/hydrophilic interactions played a crucial role in the filtration experiments with real wastewater effluent. Thus, the reported results indicated that the rejection of pharmaceutically active compounds was strongly pH-dependent, except for hydrophilic neutral compounds (acetaminophen and caffeine), which showed a pH-independent behaviour with low rejection values. (C) 2016 Elsevier B.V. All rights reserved.The authors of this work wish to gratefully acknowledge the financial support from the Spanish Ministry of Economy and Competitiveness through the project CTM2013-42342-P.García-Ivars, J.; Dura-Maria, J.; Moscardo-Carreño, C.; Carbonell Alcaina, C.; Alcaina-Miranda, MI.; Iborra Clar, MI. (2017). Rejection of trace pharmaceutically active compounds present in municipal wastewaters using ceramic fine ultrafiltration membranes: Effect of feed solution pH and fouling phenomena. Separation and Purification Technology. 175:58-71. https://doi.org/10.1016/j.seppur.2016.11.027S587117

Pharmaceutical compounds removal by adsorption with commercial and reused carbon coming from a drinking water treatment plant

[EN] The concern for the presence of pharmaceutical compounds in purified wastewater has grown in recent years. In this context, efficient and economically viable processes are required for their removal. In this study, adsorption was conducted to assess the removal of ibuprofen, caffeine, diazepam and acetaminophen, both as separated processes as in combination with a biological process in sequencing batch reactors. Removal efficiencies of these pharmaceutical active compounds were evaluated using two commercial activated carbons in granular and powder form and a discarded (after its use) activated carbon from a drinking water treatment plant. Concerning the biological treatment tests, simulated municipal wastewater was doped with 3¿mg/L of each pharmaceutical active compounds. Results showed that caffeine, acetaminophen and ibuprofen achieved excellent removal percentages, even without powder activated carbon addition (more than 94%); By contrast, whereas diazepam removal was low (lower than 50%); however, it was improved up to 68% with the powder activated carbon addition to the sequencing batch reactors. Regarding adsorption tests as separated process, ibuprofen was the pharmaceutical active compounds with the lowest removal percentage (around 50% for the granular activated carbon) and diazepam (around 80% for the granular activated carbon) was the compound with the maximum removal efficiency for the tested concentrations (between 0.5 and 3¿mg/L). Finally, results were very promising for the reused activated carbon since the removal efficiency of the pharmaceutical active compounds was higher than 90% (except for ibuprofen) when 0.5¿g/L of reused activated carbon was applied in powder form to solutions of 3¿mg/L of each pharmaceutical active compounds. In this way, a low cost activated carbon could be applied in wastewater treatment plants for pharmaceutical active compounds removal.This work has been carried out in the frame of the project IMIDTA/2017/73 granted to the company GECIVAL, S.L. by Instituto Valenciano de Competitividad Empresarial (IVACE) within the program for research and development projects for SMEs. This project has been co-financed (50%) by the operational program FEDER of Comunitat Valenciana 2014 2020.Lujan Facundo, MJ.; Iborra-Clar, MI.; Mendoza Roca, JA.; Alcaina-Miranda, MI. (2019). Pharmaceutical compounds removal by adsorption with commercial and reused carbon coming from a drinking water treatment plant. Journal of Cleaner Production. 238:1-9. https://doi.org/10.1016/j.jclepro.2019.117866S1923

Preparation of Sewage Sludge¿Based Activated Carbon for Hydrogen Sulphide Removal

[EN] The circular economy concept boosts the use of wastes as secondary raw materials in the EU renewable and sustainable framework. In wastewater treatment plants (WWTP), sludge is one of the most important wastes, and its management is being widely discussed in the last years. In this work, sewage sludge from WWTP was employed as raw material for producing activated carbon (AC) by physical-chemical activation. The prepared AC was subsequently tested for hydrogen sulphide removal in view of its further use in deodorization in a WWTP. The effects of the activation temperature and the chemical agent used (NaOH and KOH) during the activation process were studied. On the one hand, the characteristics of each AC fabricated were analysed in terms of BET (Brunauer-Emmett-Teller) surface area, pore and micropore volume, pore diameter, surface morphology and zeta potential. On the other hand, BET isotherms were also calculated. Finally, both the prepared AC and a commercial AC were tested for H2S removal from a gas stream. Results demonstrated that the optimum physical and chemical activation temperature was 600 degrees C and 1000 degrees C, respectively, and the best activated agent tested was KOH. The prepared AC showed excellent properties (specific surface area around 300 m(2)/g) for H2S removal, even better efficiencies than those achieved by the tested commercial AC.Lujan Facundo, MJ.; Iborra-Clar, MI.; Mendoza Roca, JA.; Alcaina-Miranda, MI.; Maciá, AM.; Lardin, C.; Pastor, L.... (2020). Preparation of Sewage Sludge¿Based Activated Carbon for Hydrogen Sulphide Removal. Water Air & Soil Pollution. 231(4):1-12. https://doi.org/10.1007/s11270-020-04518-wS1122314Andrade, S. N., Veloso, C. M., Fontan, R. C. I., Bonomo, R. C. F., Santos, L. S., Brito, M. J. P., & Diniz, G. A. (2018). 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H., Heo, J. E., Kim, K. D., & Huang, C. P. (2019). The adsorption characteristics of fluoride on commercial activated carbon treated with quaternary ammonium salts (Quats). Science of the Total Environment, 693, 133605.Cheng, S., Zhang, L., Ma, A., Xia, H., Peng, J., Li, C., & Shu, J. (2018). Comparison of activated carbon and iron/cerium modified activated carbon to remove methylene blue from wastewater. Journal of Environmental Sciences, 65, 92–102.Chiavola, A. (2013). Textiles. Water Environment Research, 85, 1581–1600.De Falco, G., Montagnaro, F., Balsamo, M., Erto, A., Deorsola, F. A., Lisi, L., & Cimino, S. (2018). Synergic effect of Zn and Cu oxides dispersed on activated carbon during reactive adsorption of H 2 S at room temperature. Microporous and Mesoporous Materials, 257, 135–146.Dias, J. M., Alvim-Ferraz, M. C. M., Almeida, M. F., Rivera-Utrilla, J., & Sánchez-Polo, M. (2007). Waste materials for activated carbon preparation and its use in aqueous-phase treatment: a review. Journal of Environmental Management, 85, 833–846.Donald, J., Ohtsuka, Y., & Xu, C. C. (2011). Effects of activation agents and intrinsic minerals on pore development in activated carbons derived from a Canadian peat. Materials Letters, 65, 744–747.dos Reis, G. S., Mahbub, M. K. B., Wilhelm, M., Lima, E. C., Sampaio, C. H., Saucier, C., & Dias, S. L. P. (2016). Activated carbon from sewage sludge for removal of sodium diclofenac and nimesulide from aqueous solutions. Korean Journal of Chemical Engineering, 33(11), 3149–3161.Hadi, P., Xu, M., Ning, C., Lin, C. S. K., & McKay, G. (2015). A critical review on preparation, characterization and utilization of sludge-derived activated carbons for wastewater treatment. Chemical Engineering Journal, 260, 895–906.Kacan, E. (2016). Optimum BET surface areas for activated carbon produced from textile sewage sludges and its application as dye removal. Journal of Environmental Management, 166, 116–123.Kazak, O., Eker, Y. R., Bingol, H., & Tor, A. (2018). Preparation of chemically-activated high surface area carbon from waste vinasse and its efficiency as adsorbent material. Journal of Molecular Liquids, 272, 189–197.Kimura, K., Honoki, D., & Sato, T. (2017). Effective physical cleaning and adequate membrane flux for direct membrane filtration (DMF) of municipal wastewater: up-concentration of organic matter for efficient energy recovery. Separation and Purification Technology, 181, 37–43.Kuroda, S., Nagaishi, T., Kameyama, M., Koido, K., Seo, Y., & Dowaki, K. (2018). Hydroxyl aluminium silicate clay for biohydrogen purification by pressure swing adsorption: Physical properties, adsorption isotherm, multicomponent breakthrough curve modelling, and cycle simulation. International Journal of Hydrogen Energy, 43, 16573–16588.Ladavos, A. K., Katsoulidis, A. P., Iosifidis, A., Triantafyllidis, K. S., Pinnavaia, T. J., & Pomonis, P. J. (2012). The BET equation, the inflection points of N2 adsorption isotherms and the estimation of specific surface area of porous solids. Microporous and Mesoporous Materials, 151, 126–133.Lapham, D. P., & Lapham, J. L. (2017). Gas adsorption on commercial magnesium stearate: effects of degassing conditions on nitrogen BET surface area and isotherm characteristics. International Journal of Pharmaceutics, 530, 364–376.Li, W. H., Yue, Q. Y., Gao, B. Y., Ma, Z. H., Li, Y. J., & Zhao, H. X. (2011). Preparation and utilization of sludge-based activated carbon for the adsorption of dyes from aqueous solutions. Chemical Engineering Journal, 171, 320–327.Li, F., Lei, T., Zhang, Y., Wei, J., & Yang, Y. (2015). Preparation, characterization of sludge adsorbent and investigations on its removal of hydrogen sulfide under room temperature. Frontiers of Environmental Science & Engineering, 9(2), 190–196.Li, J., Xing, X., Li, J., Shi, M., Lin, A., Xu, C., Zheng, J., & Li, R. (2018). Preparation of thiol-functionalized activated carbon from sewage sludge with coal blending for heavy metal removal from contaminated water. Environmental Pollution, 234, 677–683.Li, D., Zhou, J., Wang, Y., Tian, Y., Wei, L., Zhang, Z., Qiao, Y., & Li, J. (2019). Effects of activation temperature on densities and volumetric CO2 adsorption performance of alkali-activated carbons. Fuel, 238, 232–239.Li, Y. H., Chang, F. M., Huang, B., Song, Y. P., Zhao, H. Y., & Wang, K. J. (2020). Activated carbon preparation from pyrolysis char of sewage sludge and its adsorption performance for organic compounds in sewage. Fuel, 266, 117053.Mininni, G., Blanch, A. R., Lucena, F., & Berselli, S. (2015). EU policy on sewage sludge utilization and perspectives on new approaches of sludge management. Environmental Science and Pollution Research, 22, 7361–7374.Pandiarajan, A., Kamaraj, R., Vasudevan, S., & Vasudevan, S. (2018). OPAC (orange peel activated carbon) derived from waste orange peel for the adsorption of chlorophenoxyacetic acid herbicides from water: adsorption isotherm, kinetic modelling and thermodynamic studies. Bioresource Technology, 261, 329–341.Peng, L., Dai, H., Wu, Y., Peng, Y., & Lu, X. (2018). A comprehensive review of the available media and approaches for phosphorus recovery from wastewater. Water, Air, and Soil Pollution, 229.Pezoti, O., Cazetta, A. L., Bedin, K. C., Souza, L. S., Martins, A. C., Silva, T. L., Santos Júnior, O. O., Visentainer, J. V., & Almeida, V. C. (2016). NaOH-activated carbon of high surface area produced from guava seeds as a high-efficiency adsorbent for amoxicillin removal: kinetic, isotherm and thermodynamic studies. Chemical Engineering Journal, 288, 778–788.Ping, Q., Zheng, M., Dai, X., & Li, Y. (2020). Metagenomic characterization of the enhanced performance of anaerobic fermentation of waste activated sludge with CaO2 addition at ambient temperature: fatty acid biosynthesis metabolic pathway and CAZymes. Water Research, 170, 115309.Qiu, M., & Huang, C. (2015). Removal of dyes from aqueous solution by activated carbon from sewage sludge of the municipal wastewater treatment plant. Desalination and Water Treatment, 53, 3641–3648.Rawal, S., Joshi, B., & Kumar, Y. (2018). Synthesis and characterization of activated carbon from the biomass of Saccharum bengalense for electrochemical supercapacitors. The Journal of Energy Storage, 20, 418–426.Satya Sai, P. M., & Krishnaiah, K. (2005). Development of the pore-size distribution in activated carbon produced from coconut shell char in a fluidized-bed reactor. Industrial and Engineering Chemistry Research, 44, 51–60.Shen, F., Liu, J., Zhang, Z., Dong, Y., & Gu, C. (2018). Density functional study of hydrogen sulfide adsorption mechanism on activated carbon. Fuel Processing Technology, 171, 258–264.Sing, K. S. W., Everett, D. H., Haul, R. A. W., Moscou, L., Pierotti, R. A., Rouquerol, J., & Siemieniewska, T. (1985). Reporting physisorption data for gas/solid systems with special reference to the determination of surface area and porosity. Pure and Applied Chemistry, 57.Sulaiman, N. S., Hashim, R., Mohamad Amini, M. H., Danish, M., & Sulaiman, O. (2018). Optimization of activated carbon preparation from cassava stem using response surface methodology on surface area and yield. Journal of Cleaner Production, 198, 1422–1430.Sun, K., Huang, Q., Chi, Y., & Yan, J. (2018). Effect of ZnCl2-activated biochar on catalytic pyrolysis of mixed waste plastics for producing aromatic-enriched oil. 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Nanofiltration as tertiary treatment method for removing trace pharmaceutically active compounds in wastewater from wastewater treatment plants

[EN] The ever-increasing occurrence and persistence of pharmaceutically active compounds (PhACs) in soils, sediments, drinking water supplies and wastewater effluents are a matter of serious environmental concern for governments and researchers worldwide. Nanofiltration as tertiary treatment method can be a viable and practical tool to remove these pollutants from aquatic environments. However, organic matter present in water sources can foul the membrane surface during operation, thus being potentially able to affect the membrane performance. Therefore, fouling mechanisms could heavily influence on the removal efficiencies. The purpose of this study was to investigate the implementation of three nano- filtration membranes (TFC-SR2, NF-270 and MPS-34) and to study both the rejection of trace PhACs and the fouling mechanisms for each membrane as a function of feed solution pH. Fouling mechanisms were predicted by Hermia's model adapted to cross-flow configurations. Results demonstrated that higher removals were obtained at slightly alkaline pH, especially for anionic trace PhACs. At the same conditions, more severe fouling was observed, which resulted in strong flux declines and an increase in hydrophobicity. This indicates that the attached organic matter on the membrane surface acts as a secondary selective barrier for separation.The authors thank the financial support from the Spanish Ministry of Economy and Competitiveness through the project CTM2013-42342-P. Likewise, the authors also express their acknowledge to the personnel of the Carraixet WWTP for the kind supply of secondary effluent samples.García-Ivars, J.; Martella, L.; Massella, M.; Carbonell Alcaina, C.; Alcaina-Miranda, MI.; Iborra Clar, MI. (2017). Nanofiltration as tertiary treatment method for removing trace pharmaceutically active compounds in wastewater from wastewater treatment plants. Water Research. 125:360-373. https://doi.org/10.1016/j.watres.2017.08.070S36037312

Surface photomodification of flat-sheet PES membranes with improved antifouling properties by varying UV irradiation time and additive solution pH

Different polyethersulfone ultrafiltration membranes modified using UV irradiation in the presence of additives with different nature: hydrophilic aluminium oxide (Al2O3) nanoparticles and organic polyethylene glycol (PEG). The influence of the additive concentration, the irradiation time and the pH of the additive solution on several membrane characteristics related to its antifouling properties were investigated. These properties were analysed by means of hydrophilicity measurements (water contact angle, degree of modification, water permeability, porosity, and pore size), surface microscopic techniques (ATR-FTIR, SEM and AFM) and cross-flow filtration experiments using industrial wastewaters (residual brines from table olive processing wastewaters). Results showed that all the PES membranes modified with different PEG/Al2O3 concentrations improved the hydrophilicity of the membrane, except for membranes modified at pH 7. In addition, superior antifouling properties were provided by PES membranes modified with nano-sized Al2O3 at a concentration of 0.5%, low irradiation time (10 min) and acidic pH values (about pH 3). Therefore, surface membrane modification via UV irradiation with hydrophilic compounds is an appropriate technique to improve membrane performance applied in certain industrial fields.The authors of this work thank the financial support of CDTI (Centre for Industrial Technological Development) depending on the Spanish Ministry of Science and Innovation. The authors also thank the Center for Biomaterials and Tissue Engineering and the Electron Microscopy Service both from the Universitat Politecnica de Valencia.García Ivars, J.; Iborra Clar, MI.; Alcaina Miranda, MI.; Mendoza Roca, JA.; Pastor Alcañiz, L. (2016). Surface photomodification of flat-sheet PES membranes with improved antifouling properties by varying UV irradiation time and additive solution pH. Chemical Engineering Journal. 283:231-242. doi:10.1016/j.cej.2015.07.078S23124228

Enhancement in hydrophilicity of different polymer phase-inversion ultrafiltration membranes by introducing PEG/Al2O3 nanoparticles

The influence of the modification by additives in the characteristics of several ultrafiltration polymeric membranes was studied. Three asymmetric membranes with similar pore size (molecular weight cutoff (MWCO) of around 30 kDa) but different materials and pore microstructures – polysulfone, polyethersulfone and polyetherimide – were used. Effects of two different hydrophilic additives on membrane structure and the resulting performance were compared to determine the material with the best antifouling properties. Polyethyleneglycol (PEG) and alumina (Al2O3) were employed as additives in the phaseinversion method, N,N-Dimethylacetamide and deionized water were used as solvent and coagulant, respectively. Membranes were characterized in terms of hydraulic permeability, membrane resistance, MWCO profile and hydrophilicity (by membrane porosity and contact angle). The cross-sectional and membrane surface were also examined by microscopic techniques. Membrane antifouling properties were analysed by the experimental study of fouling/rinsing cycles using feed solutions of PEG of 35 kDa. Permeation and morphological studies showed that the addition of PEG/Al2O3 results in formation of a hydrophilic finger-like structure with macrovoids, whereas the addition of Al2O3 results in the formation of a hydrophilic structure with a dense top layer with Al2O3 nanoparticles and a porous sponge-like sublayer. Furthermore, polyethersulfone/PEG/Al2O3 membranes displayed superior antifouling properties and desirable ultrafiltration performance.The authors of this work thank the financial support of CDTI (Centre for Industrial Technological Development) depending on the Spanish Ministry of Science and Innovation. The authors also thank the Center for Biomaterials and Tissue Engineering (Universitat Politecnica de Valencia) for contact angle measurements and BASF (Germany) and General Electric (United States) for supplying the polymers used.García Ivars, J.; Alcaina Miranda, MI.; Iborra Clar, MI.; Mendoza Roca, JA.; Pastor Alcañiz, L. (2014). Enhancement in hydrophilicity of different polymer phase-inversion ultrafiltration membranes by introducing PEG/Al2O3 nanoparticles. Separation and Purification Technology. 128:45-57. doi:10.1016/j.seppur.2014.03.012S455712

Treatment of table olive processing wastewaters using novel photomodified ultrafiltration membranes as first step for recovering phenolic compounds

Table olive processing wastewaters (TOPW) have high salt concentration and total phenolic content (TPC) causing many environmental problems. To reduce them, ultrafiltration (UF) was applied for treating TOPW. However, NaCl, which is the main responsible of salinity in TOPW, and phenols are small molecules that cannot be separated by conventional UF membranes. They have serious problems caused by fouling, which can be overcome using membrane modification techniques. For these reasons, photomodification may be an effective technique to obtain a stream rich in TPC due to the changes in membrane surface properties. UV-modification in the presence of two hydrophilic compounds (polyethylene glycol and aluminium oxide) was performed to achieve membranes with high reductions of organic matter and to keep the TPC as high as possible. Commercial polyethersulfone (PES) membranes of 30 kDa were used. Surface modification was evaluated using FTIR-ATR spectroscopy and membrane performance was studied by calculating the rejection ratios of colour, chemical oxygen demand (COD) and TPC. Results demonstrated that UF is a useful pre-treatment to reduce organic matter from TOPW, obtaining a permeate rich in TPC. PES/Al2O3 membranes displayed superior antifouling properties and rejection values, keeping high the TPC (>95%). Therefore, UF using modified membranes is an appropriate and sustainable technique for treating TOPW.The authors thank the financial support of CDTI (Centre for Industrial Technological Development) depending on the Spanish Ministry of Science and Innovation. The authors also thank the Center for Biomaterials and Tissue Engineering (Universitat Politecnica de Valencia) for FTIR-ATR and contact angle measurements.García Ivars, J.; Iborra Clar, MI.; Alcaina Miranda, MI.; Mendoza Roca, JA.; Pastor Alcañiz, L. (2015). Treatment of table olive processing wastewaters using novel photomodified ultrafiltration membranes as first step for recovering phenolic compounds. Journal of Hazardous Materials. 290:51-59. doi:10.1016/j.jhazmat.2015.02.062S515929

Development of fouling-resistant polyethersulfone ultrafiltration membranes via surface UV photografting with polyethylene glycol/aluminum oxide nanoparticles

Polyethersulfone ultrafiltration membranes prepared via immersion precipitation with similar pore size were modified using UV irradiation with two nano-sized hydrophilic compounds of a different nature (an organic compound and a metal oxide). Effects of PEG/Al2O3 nanoparticles on membrane structure and the resulting performance were compared to determine the material with the best antifouling properties. Membranes were characterized by hydrophilicity (water contact angle, porosity, equilibrium water content and average pore radius), surface microscopic techniques (ATR-FTIR, SEM, EDX and AFM) and cross-flow ultrafiltration experiments (hydraulic permeability, membrane resistance and antifouling measurements). Membrane antifouling properties were analyzed by several fouling/rinsing cycles using feed solutions of PEG of 35,000 g mol 1 with a concentration of 5 g L 1.Water contact angle measurements, ATR-FTIR spectra, SEM images and EDX analysis indicated the presence of PEG/Al2O3 nanoparticles on the membrane surface. All UV-grafted membranes had higher hydraulic permeability than the unmodified membrane. Furthermore, polyethersulfone membranes photografted with 2.0 wt% PEG and 0.5 wt% Al2O3 displayed superior antifouling properties and desirable performance compared to all membranes tested. Therefore, this study proved that UV photografting of PEG/Al2O3 onto membrane surfaces is an appropriate technique for modifying polyethersulfone membranes to minimize membrane fouling.The authors of this work thank the financial support of CDTI (Centre for Industrial Technological Development) depending on the Spanish Ministry of Science and Innovation. The authors also thank the Center for Biomaterials and Tissue Engineering (Universitat Politecnica de Valencia) for ATR-FTIR and contact angle measurements and BASF (Germany) for supplying the polymers used.García Ivars, J.; Iborra Clar, MI.; Alcaina Miranda, MI.; Mendoza Roca, JA.; Pastor Alcañiz, L. (2014). Development of fouling-resistant polyethersulfone ultrafiltration membranes via surface UV photografting with polyethylene glycol/aluminum oxide nanoparticles. Separation and Purification Technology. 135:88-99. doi:10.1016/j.seppur.2014.07.056S889913