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  • 1.
    Gulshan, Samina
    et al.
    KTH Royal Institute of Technology, Sweden.
    Shafaghat, Hoda
    RISE Research Institutes of Sweden, Bioekonomi och hälsa, Bioraffinaderi och energi.
    Yang, Hanmin
    KTH Royal Institute of Technology, Sweden.
    Evangelopoulos, Panagiotis
    RISE Research Institutes of Sweden, Samhällsbyggnad, Systemomställning och tjänsteinnovation.
    Yang, Weihong
    KTH Royal Institute of Technology, Sweden.
    Performance analysis and production of aromatics for ex situ catalytic pyrolysis of engineered WEEE2024Ingår i: Journal of Analytical and Applied Pyrolysis, ISSN 0165-2370, E-ISSN 1873-250X, Vol. 179, artikel-id 106510Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Ex situ catalytic pyrolysis of engineered waste electrical and electronic equipment (WEEE) was conducted in a two-stage reactor using HZSM-5 catalyst. The effect of the catalysis temperature and the catalyst-to-feedstock (C/F) ratio on products yield, gas and oil composition, and products characterization were investigated in this study. Results indicated that lower reforming temperature and C/F ratio favored organic fractions production. The highest yield of organic fraction was obtained at a catalysis temperature of 450 °C and at a C/F ratio of 0.15, corresponding to 28.5 and 27.4 wt %, respectively. The highest selectivity toward aromatic hydrocarbons and the lowest TAN value of the organic fraction were obtained at a catalysis temperature of 450 °C and a C/F ratio of 0.2, respectively. Most of the alkali and transition metals and 23 % of Br remained in the solid residue after the catalytic pyrolysis of low-grade electronic waste (LGEW). 

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  • 2.
    Johansson, Ann-Christine
    et al.
    RISE Research Institutes of Sweden, Bioekonomi och hälsa, Bioraffinaderi och energi.
    Selander, André
    RISE Research Institutes of Sweden, Bioekonomi och hälsa, Bioraffinaderi och energi.
    Soleimanisalim, Amir H
    RISE Research Institutes of Sweden, Bioekonomi och hälsa, Bioraffinaderi och energi.
    Nordsvahn, Rebecka
    RISE Research Institutes of Sweden, Bioekonomi och hälsa, Bioraffinaderi och energi.
    Shafaghat, Hoda
    RISE Research Institutes of Sweden, Bioekonomi och hälsa, Bioraffinaderi och energi.
    Chemical recycling of complex reject streams from the paper industry via thermal and catalytic pyrolysis2024Ingår i: Journal of Analytical and Applied Pyrolysis, ISSN 0165-2370, E-ISSN 1873-250X, Vol. 181, artikel-id 106572Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Paper-based packaging is a complex multi-material composed of paper (fibers), plastics, and metals, making efficient material recycling complicated. Currently, most of the fibers are recycled into new paper products while the residual material is commonly incinerated. Therefore, to improve the circularity and reduce the fossil dependency chemical recycling is needed. In this study, recycling of the residual materials was evaluated by thermal and catalytic pyrolysis. First, screening tests were performed using five reject materials and four catalysts in an analytical scale and then, a selection of catalyst and reject materials were evaluated in lab-scale followed by a techno-economic assessment. Experimental results indicated that the conversion was more efficient if the reject had high content of plastics compared to fibers, leading to products with increased heating value, higher hydrocarbon yield and less reactive oxygenates compared to the rejects with low plastic ratio. In the thermal pyrolysis 54 % of the weight of the feedstock and 70 wt% of the carbon in the feedstock ended up in a solid organic product (wax) which contained hydrocarbons and alcohols. In the analytical catalytic pyrolysis, HZSM-5 gave the best result in terms of cracking, deoxygenation, and aromatization. Ex-situ catalytic pyrolysis using HZSM-5 resulted in an improved quality of organic liquid with reduced hydrocarbon length as well as deoxygenated and aromatic compounds. The yield of the organic liquid was up to 19 wt% and contained mainly monoaromatics. The techno-economic evaluation showed, for processing 100,000 tons year−1 residual material, the total plant investment and the annual profit are about 29 and 12 million Euros, respectively, if no incentive for treating the residual material.

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  • 3.
    Shafaghat, Hoda
    et al.
    RISE Research Institutes of Sweden, Bioekonomi och hälsa, Bioraffinaderi och energi.
    Gulshan, S
    KTH Royal Institute of Technology, Sweden.
    Johansson, Ann-Christine
    RISE Research Institutes of Sweden, Bioekonomi och hälsa, Bioraffinaderi och energi.
    Evangelopoulos, Panagiotis
    RISE Research Institutes of Sweden, Samhällsbyggnad, Systemomställning och tjänsteinnovation.
    Yang, W.
    KTH Royal Institute of Technology, Sweden.
    Selective recycling of BTX hydrocarbons from electronic plastic wastes using catalytic fast pyrolysis2022Ingår i: Applied Surface Science, ISSN 0169-4332, E-ISSN 1873-5584, Vol. 605, artikel-id 154734Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Non-catalytic and catalytic pyrolysis of two waste electrical and electronic equipment (WEEE) fractions, with two different copper contents (low- and medium-grade WEEE named as LGE and MGE, respectively), were performed using micro- and lab-scale pyrolyzers. This research aimed to fundamentally study the feasibility of chemical recycling of the WEEE fractions via pyrolysis process considering molecular interactions at the interfaces of catalyst active sites and WEEE pyrolyzates which significantly influence the chemical functionality of surface intermediates and catalysis by reorganizing the pyrolyzates near catalytic active sites forming reactive surface intermediates. Hence, Al2O3, TiO2, HBeta, HZSM-5 and spent FCC catalysts were used in in-situ micro-scale pyrolysis. Results indicated that HBeta and HZSM-5 zeolites were more suitable than other catalysts for selective production of aromatic hydrocarbons and BTX. High acidity and shape selectivity of zeotype surfaces make them attractive frameworks for catalytic pyrolysis processes aiming for light hydrocarbons like BTX. Meanwhile, the ex-situ pyrolysis of LGE and MGE were carried out using HZSM-5 in micro- and lab-scale pyrolyzers to investigate the effect of pyrolysis configuration on the BTX selectivity. Although the ex-situ pyrolysis resulted in higher formation of BTX from LGE, the in-situ configuration was more efficient to produce BTX from MGE. © 2022 The Author(s)

  • 4.
    Shafaghat, Hoda
    et al.
    RISE Research Institutes of Sweden, Bioekonomi och hälsa, Bioraffinaderi och energi.
    Johansson, Ann-Christine
    RISE Research Institutes of Sweden, Bioekonomi och hälsa, Bioraffinaderi och energi.
    Wikberg, Elena
    RISE Research Institutes of Sweden, Bioekonomi och hälsa, Bioraffinaderi och energi.
    Narvesjö, Jimmy
    RISE Research Institutes of Sweden, Bioekonomi och hälsa, Bioraffinaderi och energi.
    Wagner, Jakob Birkedal
    DTU Technical University of Denmark, Denmark.
    Öhrman, Olov
    Preem AB, Sweden.
    Customized Atmospheric Catalytic Hydropyrolysis of Biomass to High-Quality Bio-Oil Suitable for Coprocessing in Refining Units2024Ingår i: Energy & Fuels, ISSN 0887-0624, E-ISSN 1520-5029, Vol. 38, nr 6, s. 5288-5302Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This study aimed to investigate the critical elements of the biomass ex situ catalytic hydropyrolysis (CHP) concept to improve the quality of fast pyrolysis bio-oil (FPBO) for further coprocessing in a fluid catalytic cracking (FCC) refining unit. Generally, the high oxygen and low hydrogen contents of biomass result in a bio-oil with low quality, necessitating its upgrading, which can be performed as integrated in the pyrolysis process via in situ or ex situ configuration. In this work, the quality of stem wood-derived pyrolyzates (520 °C) was improved via ex situ CHP (400 °C) using a continuous bench-scale drop tube pyrolyzer (60 g h-1), and then the produced FPBO was coprocessed with vacuum gas oil (VGO) fossil oil using a lab-scale FCC unit (525 °C). CHP of stem wood was carried out using different metal-acid catalysts such as Ni/HZSM-5, Ni/HBeta, Mo/TiO2, and Pt/TiO2 at atmospheric pressure. FCC runs were performed using an equilibrium FCC catalyst and conventional fossil FCC feedstock cofed with 20 wt % stem wood-derived bio-oil in a fluidized bed reactor. Cofeeding the nonupgraded FPBO with fossil oil into the FCC unit decreased the generation of hydrocarbons in the range of gasoline and naphtha, indicating that bio-oil needs to be upgraded for further coprocessing in the FCC unit. Experimental results showed that different catalysts significantly affected the product composition and yield; Ni-based catalysts were strongly active tending to generate a high yield of gas, while Mo- and Pt-based catalysts seemed better for production of liquid with improved quality. The quality of FPBO was improved by reducing the formation of reactive oxygenates through the atmospheric CHP process. The composition of oil obtained from hydropyrolysis also showed that the yields of phenols and aromatic hydrocarbons were enhanced. © 2024 The Authors. 

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  • 5.
    Shafaghat, Hoda
    et al.
    RISE Research Institutes of Sweden, Bioekonomi och hälsa, Bioraffinaderi och energi.
    Linderberg, Mats
    RISE Research Institutes of Sweden, Bioekonomi och hälsa, Kemiska processer och läkemedel.
    Janosik, Tomasz
    RISE Research Institutes of Sweden, Bioekonomi och hälsa, Kemiska processer och läkemedel.
    Hedberg, Martin
    RISE Research Institutes of Sweden, Bioekonomi och hälsa, Kemiska processer och läkemedel.
    Wiinikka, Henrik
    RISE Research Institutes of Sweden, Bioekonomi och hälsa, Bioraffinaderi och energi.
    Sandström, Linda
    RISE Research Institutes of Sweden, Bioekonomi och hälsa, Bioraffinaderi och energi.
    Johansson, Ann-Christine
    RISE Research Institutes of Sweden, Bioekonomi och hälsa, Bioraffinaderi och energi.
    Enhanced Biofuel Production via Catalytic Hydropyrolysis and Hydro-Coprocessing2022Ingår i: Energy & Fuels, ISSN 0887-0624, E-ISSN 1520-5029, Vol. 36, nr 1, s. 450-462Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In order to successfully integrate biomass pyrolysis oils as starting materials for conventional oil refineries, upgrading of the pyrolysis oils is needed to achieve desired properties, something which can be performed either as part of the pyrolysis process and/or by separate catalytic treatment of the pyrolysis intermediate oil products. In this study, the quality of stem wood-derived pyrolysis oil was improved via ex situ catalytic hydropyrolysis in a bench-scale pyrolyzer (stage 1), followed by catalytic hydro-coprocessing with fossil co-feed in a laboratory-scale high pressure autoclave (stage 2). The effect of pyrolysis upgrading conditions was investigated based on the quality of intermediate products and their suitability for hydro-coprocessing. HZSM-5 and Pt/TiO2 catalysts (400 °C, atmospheric pressure) were employed for ex situ pyrolysis, and the NiMoS/Al2O3 catalyst (330 °C, 100 bar H2 initial pressure) was used for hydro-coprocessing of the pyrolysis oil. The application of HZSM-5 in the pyrolysis of stem wood under a N2 atmosphere decreased the formation of acids, ketones, aldehydes, and furans and increased the production of aromatic hydrocarbons and phenolics (guaiacols and phenols). Replacing HZSM-5 with Pt/TiO2 and N2 with H2 resulted in complete conversion of guaiacols and significant production of phenols, with further indications of increased stability and reduced coking tendencies.

  • 6.
    Weiland, Fredrik
    et al.
    RISE Research Institutes of Sweden, Bioekonomi och hälsa, Bioraffinaderi och energi.
    Qureshi, Muhammad
    VTT, Finland.
    Wennebro, Jonas
    RISE Research Institutes of Sweden, Bioekonomi och hälsa, Bioraffinaderi och energi.
    Lindfors, Christian
    VTT, Finland.
    Ohra-Aho, Taina
    VTT, Finland.
    Shafaghat, Hoda
    RISE Research Institutes of Sweden, Bioekonomi och hälsa, Bioraffinaderi och energi.
    Johansson, Ann-Christine
    RISE Research Institutes of Sweden, Bioekonomi och hälsa, Bioraffinaderi och energi.
    Entrained flow gasification of polypropylene pyrolysis oil2021Ingår i: Molecules, ISSN 1431-5157, E-ISSN 1420-3049, Vol. 26, nr 23, artikel-id 7317Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Petrochemical products could be produced from circular feedstock, such as waste plastics. Most plants that utilize syngas in their production are today equipped with entrained flow gasifiers, as this type of gasifier generates the highest syngas quality. However, feeding of circular feedstocks to an entrained flow gasifier can be problematic. Therefore, in this work, a two-step process was studied, in which polypropylene was pre-treated by pyrolysis to produce a liquid intermediate that was easily fed to the gasifier. The products from both pyrolysis and gasification were thoroughly characterized. Moreover, the product yields from the individual steps, as well as from the entire process chain, are reported. It was estimated that the yields of CO and H2 from the two-step process were at least 0.95 and 0.06 kg per kg of polypropylene, respectively, assuming that the pyrolysis liquid and wax can be combined as feedstock to an entrained flow gasifier. On an energy basis, the energy content of CO and H2 in the produced syngas corresponded to approximately 40% of the energy content of the polypropylene raw material. This is, however, expected to be significantly improved on a larger scale where losses are proportionally smaller. © 2021 by the authors. 

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