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•Pyrolysis was applied for adsorbent production for paper mill residues valorization.•Pyrolysed paper mill sludge was tested for the removal of an antidepressant from ...water.•Adsorbents were produced by environmentally friendly methods without activation steps.•Primary sludge resulted in higher porous and efficient adsorbents than biological sludge.•Best results were obtained for primary sludge pyrolysed at 800°C for 150min.
This work describes the production of alternative adsorbents from industrial residues and their application for the removal of a highly consumed antidepressant (citalopram) from water. The adsorbents were produced by pyrolysis of both primary and biological paper mill sludge at different temperatures and residence times. The original sludge and the produced chars were fully characterized by elemental and proximate analyses, total organic carbon, specific surface area (BET), N2 isotherms, FTIR, 13C and 1H solid state NMR and SEM. Batch kinetic and equilibrium experiments were carried out to describe the adsorption of citalopram onto the produced materials. The fastest kinetics and the highest adsorption capacity were obtained using primary sludge pyrolysed at 800°C during 150min. The use of pyrolysed paper mill sludge for the remediation of contaminated waters might constitute an interesting application for the valorization of those wastes.
Pulp and paper industry produces massive amounts of sludge from wastewater treatment, which constitute an enormous environmental challenge. A possible management option is the conversion of sludge ...into carbon-based adsorbents to be applied in water remediation. For such utilization it is important to investigate if sludge is a consistent raw material originating reproducible final materials (either over time or from different manufacturing processes), which is the main goal of this work. For that purpose, different primary (PS) and biological sludge (BS) batches from two factories with different operation modes were sampled and subjected to pyrolysis (P materials) and to pyrolysis followed by acid washing (PW materials). All the materials were characterized by proximate analysis, total organic carbon (TOC) and inorganic carbon (IC), attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) and N2 adsorption isotherms (specific surface area (SBET)and porosity determination). Sludge from the two factories proved to have distinct physicochemical properties, mainly in what concerns IC. After pyrolysis, the washing step was essential to reduce IC and to considerably increase SBET, yet with high impact in the final production yield. Among the materials here produced, PW materials from PS were those having the highest SBET values (387–488 m2 g−1). Overall, it was found that precursors from different factories might originate final materials with distinct characteristics, being essential to take into account this source of variability when considering paper mill sludge as a raw material. Nevertheless, for PS, low variability was found between batches, which points out to the reliability of such residues to be used as precursors of carbon adsorbents.
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•Pyrolytic conversion of paper mill sludge into carbon adsorbents was evaluated.•Consistency of raw materials and produced adsorbents was assessed for the 1st time.•Primary (PS) and biological sludge (BS) from two different factories were sampled.•Sludge from different factories might originate materials with distinct properties.•PS presented low variability between batches revealing consistency.
This work describes the single adsorption of seven pharmaceuticals (carbamazepine, oxazepam, sulfamethoxazole, piroxicam, cetirizine, venlafaxine and paroxetine) from water onto a commercially ...available activated carbon and a non-activated carbon produced by pyrolysis of primary paper mill sludge. Kinetics and equilibrium adsorption studies were performed using a batch experimental approach. For all pharmaceuticals, both carbons presented fast kinetics (equilibrium times varying from less than 5 min to 120 min), mainly described by a pseudo-second order model. Equilibrium data were appropriately described by the Langmuir and Freundlich isotherm models, the last one giving slightly higher correlation coefficients. The fitted parameters obtained for both models were quite different for the seven pharmaceuticals under study. In order to evaluate the influence of water solubility, log Kow, pKa, polar surface area and number of hydrogen bond acceptors of pharmaceuticals on the adsorption parameters, multiple linear regression analysis was performed. The variability is mainly due to log Kow followed by water solubility, in the case of the waste-based carbon, and due to water solubility in the case of the commercial activated carbon.
•Adsorption of 7 pharmaceuticals onto activated and paper mill sludge carbons was studied.•The activated carbon is highly efficient on the removal of pharmaceuticals from water.•Significant differences in the adsorption affinity were obtained between pharmaceuticals.•The influence of pharmaceuticals properties was evaluated by linear regression analysis.•log Kow and water solubility were the main properties affecting adsorption.
Cork powder and granules are the major subproducts of the cork industry, one of the leading economic activities in Portugal and other Mediterranean countries. Many applications have been envisaged ...for this product, from cork stoppers passing through the incorporation in agglomerates and briquettes to the use as an adsorbent in the treatment of gaseous emissions, waters and wastewaters. This paper aims at reviewing the state of the art on the properties of cork and cork powder and their application in adsorption technologies. Cork biomass has been used on its original form as biosorbent for heavy metals and oils, and is also a precursor of activated carbons for the removal of emerging organic pollutants in water and VOCs in the gas phase. Through this literature review, different potential lines of research not yet explored can be more easily identified.
► Outline of cork powder and granules' chemical and physical properties. ► Overview of the application of cork powder and granules in biosorption. ► Review of previously reported methods for activated carbon preparation from cork. ► Summary of the main applications of cork-based activated carbons in adsorption.
•Valorisation of agricultural and industrial wastes by combustion and pyrolysis.•Agricultural wastes showed the highest heating values (HHVs).•Combustion of agricultural wastes are promising for ...energy applications.•Pyrolysis of industrial wastes produces materials for adsorption applications.
Combustion and pyrolysis processes were assessed and compared for two types of lignocellulosic biowastes: agricultural (Eucalyptus bark, grape seeds, peach stones, walnut shells, olive waste and peanut shells) and industrial (primary and biological paper mill sludge) biowastes. They were characterized by elemental, proximate and thermal analyses; the pyrolysis behaviour was studied by thermogravimetric analysis and the gases produced were identified using mass spectrometry. Agricultural biowastes showed the highest calorific values, close to the fossil fuel values (20–30MJkg−1) and, in general, emission of gases containing the carbon element (CH4, C2H2, CO and CO2) was higher than that of the tested industrial biowastes, making the agricultural biowastes highly competitive for combustion applications such as gas fuel. Further, the solid product which resulted from the pyrolysis of industrial biowastes is a material with large specific surface area, which is a good characteristic for possible applications as adsorbent in water remediation.
This work describes the adsorptive removal of three widely consumed psychiatric pharmaceuticals (carbamazepine, paroxetine and oxazepam) from ultrapure water. Two different adsorbents were used: a ...commercial activated carbon and a non-activated waste-based carbon (PS800-150-HCl), produced by pyrolysis of primary paper mill sludge. These adsorbents were used in single, binary and ternary batch experiments in order to determine the adsorption kinetics and equilibrium isotherms of the considered pharmaceuticals. For the three drugs and both carbons, the equilibrium was quickly attained (with maximum equilibrium times of 15 and 120 min for the waste-based and the commercial carbons, respectively) even in binary and ternary systems. Single component equilibrium data were adequately described by the Langmuir model, with the commercial carbon registering higher maximum adsorption capacities (between 272 ± 10 and 493 ± 12 μmol g−1) than PS800-150-HCl (between 64 ± 2 and 74 ± 1 μmol g−1). Multi-component equilibrium data were also best fitted by the single component Langmuir isotherm, followed by the Langmuir competitive model. Overall, competitive effects did not largely affect the performance of both adsorbents. Binary and ternary systems maintained fast kinetics, the individual maximum adsorption capacities were not lower than half of the single component systems and both carbons presented improved total adsorption capacities for multi-component solutions.
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•Single and multi-component adsorption of 3 pharmaceuticals were studied.•Selected adsorbents were waste-based and commercial activated carbons.•Adsorption data were fitted to single and multi-component isotherm models.•Single-component isotherms adequately described the multi-component data.•Competitive effects did not largely affected the performance of both adsorbents.
Tricaine methanesulfonate (MS-222) has been widely used in intensive aquaculture systems to control stress during handling and confinement operations. This compound is dissolved in the water tanks ...and, once it is present in the Recirculating Aquaculture Systems (RASs), MS-222 can reach the environment by the discharge of contaminated effluents. The present work proposes the implementation of the adsorption process in the RASs, using pyrolysed biological paper mill sludge as adsorbent, to remove MS-222 from aquaculture wastewater. Adsorption experiments were performed under extreme operating conditions, simulating those corresponding to different farmed fish species: temperature (from 8 to 30 °C), salinity (from 0.8 to 35‰) and different contents of organic and inorganic matter in the aquaculture wastewater. Furthermore, the MS-222 adsorption from a real aquaculture effluent was compared with that from ultrapure water. Under the studied conditions, the performance of the produced adsorbent remained mostly the same, removing satisfactorily MS-222 from water. Therefore, it may be concluded that the produced adsorbent can be employed in intensive aquaculture wastewater treatment with the same performance independently of the farmed fish species.
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•Contaminated aquaculture wastewater has been treated and recycled.•Adsorption process can be implemented in recirculating aquaculture systems.•Adsorbents were tested for the removal of MS-222 from aquaculture wastewater.•Paper mill sludge-based carbons displayed fast adsorption kinetics.•Temperature, salinity and organic matter didn't affect the performance of biochars.
This study evaluates the possibility of adding value to cork granulates, byproducts of cork processing, by using them as biosorbents and precursors of activated carbons. Activation was carried out by ...impregnation with phosphoric acid followed by pyrolysis under N2 flow. Furthermore, biosorbents were treated with a cationic surfactant and activated carbons were subject to a second pyrolysis under propene with the objective of improving hydrophobicity. Physico-chemical, textural, and surface characterization of the materials was carried out employing, among others, N2 adsorption isotherms, Fourier transform infrared (FTIR) spectroscopy, potentiometric titration, temperature programmed desorption (TPD), and immersion calorimetry. Selected samples were tested in the removal of sunflower oil emulsified in water. Activated carbons with higher surface area and lower amount of acidic surface groups showed higher uptake capacity for sunflower oil.
Introdução: Este caso descreve um dos efeitos adversos possíveis da contraceção intrauterina, nomeadamente do dispositivo intrauterino de cobre (Cu-DIU), e explora o procedimento a realizar no âmbito ...dos cuidados de saúde primários (CSP). Descrição do caso: Em outubro de 2019, a utente optou por Cu-DIU e realizou uma ecografia pré-procedimento (sem alterações). Em fevereiro de 2020 foi colocado um Cu-DIU nos CSP, o que ocorreu sem intercorrências; pediu-se ecografia de controlo. Devido ao contexto pandémico, a utente não a realizou e manteve método de barreira. Em março de 2021, a ecografia realizada não identificou o Cu-DIU. A utente negou perceção de expulsão do dispositivo ou outros sintomas. Na observação não foram detetados os fios do Cu-DIU, pelo que se solicitou radiografia abdominal. Realizada em abril de 2021, esta mostrava o dispositivo “na zona média da escavação pélvica, em posição oblíqua de perfil”. Uma nova ecografia ginecológica identificou o DIU na “escavação pélvica, em topografia extrauterina, lateralizado à esquerda do útero”. A utente foi encaminhada para consulta hospitalar urgente e notificou-se a ocorrência à Unidade de Vigilância de Produtos de Saúde (UVPS), da Direção de Produtos de Saúde (DPS) do INFARMED. Em consulta de ginecologia, em junho de 2021, a utente ficou inscrita para laparoscopia para remoção de Cu-DIU e salpingectomia bilateral para contraceção definitiva. Comentário: Este caso alerta para a importância da avaliação ecográfica, após colocação de dispositivos intrauterinos, para confirmação da sua localização e garantia, por um lado, da eficácia do método e, por outro, da rápida deteção de complicações. Pretendeu-se ainda fazer uma breve revisão do procedimento a adotar em casos semelhantes: realização de exame físico e exames complementares de diagnóstico, participação às autoridades competentes e referenciação precoce à ginecologia para a rápida resolução da situação.
Adsorption process is an excellent process to remove fish anaesthetics from water.The use of PAC resulted in high adsorption capacities, between 289 and 631mgg⿿1.Biochars resulted in 4 and 8 times ...lower adsorption capacity than that for PAC.Paper mill sludge-based adsorbents seem to be a promising alternative to PAC.
Tricaine methanesulfonate (MS-222), benzocaine and 2-phenoxyethanol (2-PE) are widely used in intensive aquaculture systems to control stress during handling and confinement operations. This work aimed to study the adsorptive removal of these anaesthetics from water, comparing two waste-based adsorbents produced by pyrolysis of paper mill sludge with a commercial activated carbon. The use of commercial activated carbon resulted in maximum adsorption capacities of 631, 435 and 289mgg⿿1 for MS-222, benzocaine and 2-PE, respectively (obtained by the fitting of Langmuir-Freundlich model), which are between 4 and 8 times higher than those determined for the alternative adsorbents. Even so, the obtained results point to the promissory utilization of these waste-based adsorbents in Recirculating Aquaculture Systems, as an integrated way of managing such residues and treatment of aquaculture waters contaminated with anaesthetics.
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