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Farooq, U., Danish, M., Lu, S., Naqvi, M., Qiu, Z. & Sui, Q. (2018). A step forward towards synthesizing a stable and regeneratable nanocomposite for remediation of trichloroethene. Chemical Engineering Journal, 347, 660-668
Öppna denna publikation i ny flik eller fönster >>A step forward towards synthesizing a stable and regeneratable nanocomposite for remediation of trichloroethene
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2018 (Engelska)Ingår i: Chemical Engineering Journal, ISSN 1385-8947, E-ISSN 1873-3212, Vol. 347, s. 660-668Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

Synthesizing supported heterogeneous catalysts is always considered as a persistent approach for degradation of contaminants. However, the stability of these nanocomposites and improvement of process conditions influencing target pollutants degradation are still limited. Herein, on the basis of self-adhesive nature of polydopamine (PDA) and its strong electrostatic interaction with metallic ions, we synthesized a facile, stable, magnetically separable, and environmentally benign PDA decorated, reduced graphene oxide (rGO) supported Fe nanocatalyst (PDA@Fe/rGO). The effects of process variables (pH, PDA@Fe/rGO, and persulphate (PS) dose) on the degradation performance of trichloroethene (TCE), a model chlorinated organic pollutant selected in this study, were investigated. PDA not only encapsulated the host Fe/rGO magnetic particles but also exhibited high magnetization. PDA wrapping tremendously enhanced the thermal stability of nanocatalyst with just 24.1% weight loss at elevated temperature compared to solo Fe/rGO (40.2%). Moreover, TCE degradation mechanism was interpreted by ESR and radical scavenger tests, validating OH[rad], SO4 [rad]− and O2 [rad]− radicals being responsible for TCE degradation. Considering its eminent catalytic activity, simple synthesis approach and excellent kinetics, this recyclable and improved PDA assisted Fe/rGO nanocatalyst further opens a door for practical implementation in the field of contaminated groundwater remediation. 

Nationell ämneskategori
Annan teknik
Identifikatorer
urn:nbn:se:mdh:diva-39190 (URN)10.1016/j.cej.2018.04.120 (DOI)000432884900065 ()2-s2.0-85046093729 (Scopus ID)
Tillgänglig från: 2018-05-11 Skapad: 2018-05-11 Senast uppdaterad: 2018-07-25Bibliografiskt granskad
Naqvi, S. R. & Naqvi, M. (2018). Catalytic fast pyrolysis of rice husk: Influence of commercial and synthesized microporous zeolites on deoxygenation of biomass pyrolysis vapors. International journal of energy research (Print), 42(3), 1352-1362
Öppna denna publikation i ny flik eller fönster >>Catalytic fast pyrolysis of rice husk: Influence of commercial and synthesized microporous zeolites on deoxygenation of biomass pyrolysis vapors
2018 (Engelska)Ingår i: International journal of energy research (Print), ISSN 0363-907X, E-ISSN 1099-114X, Vol. 42, nr 3, s. 1352-1362Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

Research on utilization of abundant rice residue for valuable bioenergy products is still not explored completely. A simple, robust, cheap, and one-step fast pyrolysis reactor is still a key demand for production of bioenergy products, ie, high quality bio-oil and biochar. Bio-oil extracted from fast pyrolysis does not have adequate quality (eg, acidic and highly oxygenated). Catalytic fast pyrolysis using zeolites in the fast pyrolysis process effectively reduces the oxygen content (no H-2 required). In this paper, the zeolites with different pore sizes and shapes (small pore, SAPO-34 (0.56) and ferrierite (30); medium pore, ZSM-5 (30), MCM-22 (30), and ITQ-2 (30); and large pore zeolite, mordenite (30)) were tested in a drop-type fixed-bed pyrolyzer. Catalytic deoxygenation is conducted at 450 degrees C at the catalyst/biomass ratio of 0.1. Zeolite catalysts, its pore size and shape, could influence largely on deoxygenation. It was found that the small pore zeolites did not produce aromatics as compared to higher amount of aromatics formed in case of medium pore zeolites. ZSM-5 and ITQ-2 zeolites were especially efficient for the higher deoxygenation of biomass pyrolysis vapors due to better pore dimension and higher acidity.

Ort, förlag, år, upplaga, sidor
WILEY, 2018
Nyckelord
acidity, biomass pyrolysis, deoxygenation, micropore topology, zeolites
Nationell ämneskategori
Energiteknik
Identifikatorer
urn:nbn:se:mdh:diva-38790 (URN)10.1002/er.3943 (DOI)000425185500038 ()2-s2.0-85034214248 (Scopus ID)
Tillgänglig från: 2018-03-01 Skapad: 2018-03-01 Senast uppdaterad: 2018-11-05Bibliografiskt granskad
Salman, C. A., Naqvi, M., Thorin, E. & Yan, J. (2018). Gasification process integration with existing combined heat and power plants for polygeneration of dimethyl ether or methanol: A detailed profitability analysis. Applied Energy, 226, 116-128
Öppna denna publikation i ny flik eller fönster >>Gasification process integration with existing combined heat and power plants for polygeneration of dimethyl ether or methanol: A detailed profitability analysis
2018 (Engelska)Ingår i: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 226, s. 116-128Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

Combustion of waste for cogeneration of heat and power is the most convenient and practical choice to carry out through combined heat and power (CHP) plants. But, seasonal variation in heat demand throughout the year affects the operation of CHP plants. This fluctuation in the CHP operation cause less annual operating hours for the plant equipment and is also not profitable for stakeholders. This study aims to assess the technical potential of integrated gasification process with existing CHP plants for either dimethyl ether (DME) or methanol production through refuse-derived fuel (RDF). Process integration considers that the CHP plant provides the necessary heat for biofuel synthesis during off-peak hours. Mass and heat integration methods are used to develop and simulate the polygeneration processes for heat, power, and biofuel production. Both technical and economic indicators are reported and compared to assess the potential for both biofuels through process integration. Annual operation data of a real CHP plant has been extracted to evaluate the integrated processes. A flexible gasification configuration is selected for the integrated approach i.e. CHP runs at full load to provide the heat demand and only the excess heat of CHP plant is utilized for biofuel production. The energetic efficiencies of the polygeneration systems are compared with the standalone systems. Technical analysis of process integration shows the enhancement of the operational capacity of CHP during off-peak hours and it can produce biofuels without compromising the annual heat demand. Production of methanol through process integration shows ∼67% energetic efficiency while methanol production gives ∼65%. The efficiencies are higher than standalone DME and methanol processes (51% and 53%, respectively) but lower than standalone CHP plant i.e. 81%, however the process integration increases the operating time of the CHP plant with more economic benefits. Economic analysis coupled with uncertainty analysis through Monte Carlo simulations shows that by integrating CHP with gasifier to produce biofuels is significantly profitable as compared with only heat and electricity production. But, DME as a potential product shows more economic benefits than methanol. The uncertainty analysis through Monte Carlo simulations shows that the profitable probability of DME as a product in future is also greater than methanol due to higher DME selling price. The uncertainty analysis further shows that prices of DME and methanol with waste biomass prices in future will have a greater impact on the economic performance of the proposed polygeneration process. 

Nationell ämneskategori
Energiteknik
Identifikatorer
urn:nbn:se:mdh:diva-39632 (URN)10.1016/j.apenergy.2018.05.069 (DOI)000441688100011 ()2-s2.0-85047756868 (Scopus ID)
Tillgänglig från: 2018-06-07 Skapad: 2018-06-07 Senast uppdaterad: 2018-10-11Bibliografiskt granskad
Naqvi, S. R., Bibi, A., Naqvi, M., Noor, T., Nizami, A.-S., Rehan, M. & Ayoub, M. (2018). New trends in improving gasoline quality and octane through naphtha isomerization: a short review. APPLIED PETROCHEMICAL RESEARCH, 8(3), 131-139
Öppna denna publikation i ny flik eller fönster >>New trends in improving gasoline quality and octane through naphtha isomerization: a short review
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2018 (Engelska)Ingår i: APPLIED PETROCHEMICAL RESEARCH, ISSN 2190-5533, Vol. 8, nr 3, s. 131-139Artikel, forskningsöversikt (Refereegranskat) Published
Abstract [en]

The octane enhancement of light straight run naphtha is one of the significant solid acid catalyzed processes in the modern oil refineries due to limitations of benzene, aromatics, and olefin content in gasoline. This paper aims to examine the role of various catalysts that are being utilized for the isomerization of light naphtha with an ambition to give an insight into the reaction mechanism at the active catalyst sites, and the effect of various contaminants on catalyst activity. In addition, different technologies used for isomerization process are evaluated and compared by different process parameters.

Ort, förlag, år, upplaga, sidor
SPRINGER HEIDELBERG, 2018
Nyckelord
Catalyst, Isomerization, Light naphtha, Octane number, Oil refineries
Nationell ämneskategori
Energiteknik
Identifikatorer
urn:nbn:se:mdh:diva-40934 (URN)10.1007/s13203-018-0204-y (DOI)000443264000001 ()
Tillgänglig från: 2018-09-13 Skapad: 2018-09-13 Senast uppdaterad: 2018-09-13Bibliografiskt granskad
Naqvi, M., Dahlquist, E., Yan, J., Naqvi, S. R., Nizami, A. S., Salman, C. A., . . . Qureshi, A. S. (2018). Polygeneration system integrated with small non-wood pulp mills for substitute natural gas production. Applied Energy, 224, 636-646
Öppna denna publikation i ny flik eller fönster >>Polygeneration system integrated with small non-wood pulp mills for substitute natural gas production
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2018 (Engelska)Ingår i: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 224, s. 636-646Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

This study aims to examine the potential substitute natural gas (SNG) production by integrating black liquor gasification (BLG) island with a small wheat straw-based non-wood pulp mills (NPM), which do not employ the black liquor recovery cycle. For such integration, it is important to first build knowledge on expected improvements in an overall integrated non-wood pulp mill energy system using the key performance indicators. O2-blown circulating fluidized bed (CFB) gasification with direct causticization is integrated with a reference small NPM to evaluate the overall performance. A detailed economic analysis is performed together with a sensitivity analysis based on variations in the rate of return due to varying biomass price, total capital investment, and natural gas prices. The quantitive results showed considerable SNG production but significantly reduced electricity production. There is a substantial CO2 abatement potential combining CO2 capture and CO2 mitigation from SNG use replacing compressed natural gas (CNG) or gasoline. The economic performance through sensitivity analysis reflects significant dependency on both substitute natural gas production and natural gas market price. Furthermore, the solutions to address the challenges and barriers for the successful commercial implementation of BLG based polygeneration system at small NPMs are discussed. The system performance and discussion on the real application of integrated system presented in this article form a vital literature source for future use by large number of small non-wood pulp industries.

Ort, förlag, år, upplaga, sidor
Elsevier Ltd, 2018
Nationell ämneskategori
Energiteknik
Identifikatorer
urn:nbn:se:mdh:diva-39297 (URN)10.1016/j.apenergy.2018.05.005 (DOI)000436901400049 ()2-s2.0-85046790342 (Scopus ID)
Tillgänglig från: 2018-05-24 Skapad: 2018-05-24 Senast uppdaterad: 2018-07-19Bibliografiskt granskad
Naqvi, S. R., Jamshaid, S., Naqvi, M., Farooq, W., Niazi, M. B., Aman, Z., . . . Afzal, W. (2018). Potential of biomass for bioenergy in Pakistan based on present case and future perspectives. Renewable & sustainable energy reviews, 81, 1247-1258
Öppna denna publikation i ny flik eller fönster >>Potential of biomass for bioenergy in Pakistan based on present case and future perspectives
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2018 (Engelska)Ingår i: Renewable & sustainable energy reviews, ISSN 1364-0321, E-ISSN 1879-0690, Vol. 81, s. 1247-1258Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

Future energy security and environmental issues are major driving forces for increased biomass utilization globally and especially in developing countries like Pakistan. For efficient utilization of indigenous biomass resources in the future energy mix, it is important to gain knowledge of current energy system in various sectors. Some of the technologies and initiatives are under development to achieve transition from non-renewable resources to renewable resources, and reducing fossil fuel dependency and greenhouse gas emissions. Recently, number of proposals has been presented for the development of sustainable biofuels production methods for promise for accelerating a shift away from an unsustainable approach to possible sustainable production practices or a sustainable social, economic and environment. This article presents an extensive literature review of the biomass-based renewable energy potential in Pakistan based on current energy scenario and future perspectives. It also highlights the availability of the indigenous and local biomass resources and potential biomass conversion technologies to convert such resources to bioenergy. The drivers for utilization of indigenous biomass resources in future energy mix and challenges regarding awareness among stakeholders and R&D to fill knowledge gaps are economically restraints. The article concludes with suggestions on future directions and policies for effective implementation of biomass based renewable energy production.

Ort, förlag, år, upplaga, sidor
Elsevier Ltd, 2018
Nyckelord
Agriculture residues, Biofuels, Future energy mix, Gasification, Waste
Nationell ämneskategori
Energiteknik
Identifikatorer
urn:nbn:se:mdh:diva-36553 (URN)10.1016/j.rser.2017.08.012 (DOI)000417070500092 ()2-s2.0-85029396564 (Scopus ID)
Tillgänglig från: 2017-10-12 Skapad: 2017-10-12 Senast uppdaterad: 2017-12-21Bibliografiskt granskad
Salman, C. A., Naqvi, M., Thorin, E. & Yan, J. (2017). A polygeneration process for heat, power and DME production by integrating gasification with CHP plant: Modelling and simulation study. Energy Procedia, 142, 1749-1758
Öppna denna publikation i ny flik eller fönster >>A polygeneration process for heat, power and DME production by integrating gasification with CHP plant: Modelling and simulation study
2017 (Engelska)Ingår i: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 142, s. 1749-1758Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

Biofuels are a good substitute for the transport sector petroleum fuels to minimize carbon footprint and greenhouse gases emissions. Di-Methyl Ether (DME) is one such alternative with properties similar to liquefied petroleum gas but with lower SOx, NOx, and particulate emissions. In this work, a polygeneration process, integrating an existing combined heat and power (CHP) plant with biomass gasification to synthesize DME, is proposed and modelled. Process integration is based on a hypothesis that the CHP plant provides the necessary heat to run the co-located gasification plant for DME synthesis and the waste heat from the gasification process is recovered and transferred to the CHP plant. The feed for gasification is taken as refuse derived fuel (RDF) instead of conventional wood derived biomass. The process integration leads to higher overall combined efficiency (up to 71%) which is greater than stand-alone efficiencies (up to 63%) but lower than stand-alone CHP plant efficiency (73.2%). The further technical evaluation shows that the efficiency of the polygeneration process is depends heavily on the gasifier capacity integrated with the existing CHP plant and also on the conversion route selected for DME synthesis i.e. recycling of unconverted syngas to the DME reactor or transferring it to the boiler of the CHP plant. The simulation results also indicate that once-through conversion yields less DME than recycling, but at the same time, once-through conversion affects the district heat and electric power production of the CHP plant lesser than by using the recycling route.

Ort, förlag, år, upplaga, sidor
Elsevier Ltd, 2017
Nationell ämneskategori
Energiteknik
Identifikatorer
urn:nbn:se:mdh:diva-38721 (URN)10.1016/j.egypro.2017.12.559 (DOI)000452901601139 ()2-s2.0-85041530043 (Scopus ID)
Tillgänglig från: 2018-03-01 Skapad: 2018-03-01 Senast uppdaterad: 2019-01-24Bibliografiskt granskad
Naqvi, S. R., Uemura, Y., Yusup, S., Nishiyama, N. & Naqvi, M. (2017). Catalytic Consequences of Micropore Topology on Biomass Pyrolysis Vapors over Shape Selective Zeolites. In: Energy Procedia: . Paper presented at 8th International Conference on Applied Energy, ICAE 2016, 8 October 2016 through 11 October 2016 (pp. 557-561). Elsevier Ltd
Öppna denna publikation i ny flik eller fönster >>Catalytic Consequences of Micropore Topology on Biomass Pyrolysis Vapors over Shape Selective Zeolites
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2017 (Engelska)Ingår i: Energy Procedia, Elsevier Ltd , 2017, s. 557-561Konferensbidrag, Publicerat paper (Refereegranskat)
Abstract [en]

Research on utilization of abundant rice residue for valuable bioenergy products is still not explored completely. A simple, robust, cheap and one step fast pyrolysis reactor is still a key demand for production of bioenergy products, i.e. high quality bio-oil and bio char. Bio-oil produced from fast pyrolysis has poor quality (e.g. acidic and highly oxygenated). Catalytic fast pyrolysis using zeolites in the fast pyrolysis process effectively reduce the oxygen content (no H2 required). In this paper, zeolites having a variety of pore size and shape (small pore: SAPO-34 (0.56), Ferriertite (20), medium pore: ZSM-5 (23), MCM-22 (20), ITQ-2 (20) and large pore zeolite Mordenite (20) were tested in a drop type fixed-bed pyrolyzer. The catalytic deoxygenation is conducted at 450°C at the catalyst/biomass ratio of 0.1. Zeolite catalysts, its pore size and shape could influence largely on deoxygenation. Small pore zeolites did not produce aromatics while medium pore zeolites formed higher amount of aromatics. ZSM-5 and ITQ-2 zeolites were especially efficient for the higher deoxygenation of biomass pyrolysis vapors due to better pore dimension and higher acidity. © 2017 The Authors.

Ort, förlag, år, upplaga, sidor
Elsevier Ltd, 2017
Nyckelord
Biomass, Characterization, Deoxygenation, Fixed bed pyrolyzer, Pyrolysis oil, Zeolites, Biofuels, Catalysts, Pore size, Pyrolysis, Bioenergy products, Biomass pyrolysis, Deoxygenations, Fast pyrolysis process, Fixed bed, Small-pore zeolites, Zeolite catalyst
Nationell ämneskategori
Energiteknik
Identifikatorer
urn:nbn:se:mdh:diva-36069 (URN)10.1016/j.egypro.2017.03.356 (DOI)000404967900085 ()2-s2.0-85020712294 (Scopus ID)
Konferens
8th International Conference on Applied Energy, ICAE 2016, 8 October 2016 through 11 October 2016
Tillgänglig från: 2017-07-06 Skapad: 2017-07-06 Senast uppdaterad: 2018-07-25Bibliografiskt granskad
Naqvi, S. R., Naqvi, M., Noor, T., Hussain, A., Iqbal, N., Uemura, Y. & Nishiyama, N. (2017). Catalytic Pyrolysis Of Botryococcus Braunii (microalgae) Over Layered and Delaminated Zeolites For Aromatic Hydrocarbon Production. In: Yan, J Wu, J Li, H (Ed.), PROCEEDINGS OF THE 9TH INTERNATIONAL CONFERENCE ON APPLIED ENERGY: . Paper presented at 9th International Conference on Applied Energy (ICAE), AUG 21-24, 2017, Cardiff, ENGLAND (pp. 381-385). ELSEVIER SCIENCE BV
Öppna denna publikation i ny flik eller fönster >>Catalytic Pyrolysis Of Botryococcus Braunii (microalgae) Over Layered and Delaminated Zeolites For Aromatic Hydrocarbon Production
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2017 (Engelska)Ingår i: PROCEEDINGS OF THE 9TH INTERNATIONAL CONFERENCE ON APPLIED ENERGY / [ed] Yan, J Wu, J Li, H, ELSEVIER SCIENCE BV , 2017, s. 381-385Konferensbidrag, Publicerat paper (Refereegranskat)
Abstract [en]

Botryococcus braunii (B. Braunii) is considered as due to its high capability of large aromatic contents, prominent green microalgae as a renewable energy resource. The aim and novelty of this work is to exploit the pyrolysis characteristics of microalgae with layered and delaminated zeolites using Py-GC/MS. No catalyst and catalytic pyrolysis was compared to evaluate product components formed. Further, the catalytic pyrolysis of botryococcus braunii was carried out in the presence of two zeolites with different pore topology and acidity. The results from non-catalytic microalgae pyrolysis were compared to catalytic pyrolysis together with different catalysts to biomass ratios for aromatic hydrocarbons production. Py-GC/MS results showed the aromatic hydrocarbon production (area%) was significantly improved from zeolite catalytic pyrolysis than non-catalytic pyrolysis. The increase in catalyst to biomass ratio (3:1 and 5:1) resulted in higher aromatic hydrocarbon production. As the catalyst to biomass ratio increased, it is observed that aromatic hydrocarbon content increased as compared to low catalyst to biomass ratio. In addition, ITQ-2 zeolite generated higher aromatic hydrocarbons. This might be due to better pore structure and acidity of delaminated structure as compared to layered structure. This delaminated topology enhances the reactant diffusion and reduces the secondary cracking.

Ort, förlag, år, upplaga, sidor
ELSEVIER SCIENCE BV, 2017
Serie
Energy Procedia, ISSN 1876-6102 ; 142
Nyckelord
Catalytic pyrolysis, Botryococcus braunii, Py-GC/MS, MCM-22, ITQ-2
Nationell ämneskategori
Energiteknik
Identifikatorer
urn:nbn:se:mdh:diva-42255 (URN)10.1016/j.egypro.2017.12.060 (DOI)000452901600059 ()2-s2.0-85041518733 (Scopus ID)
Konferens
9th International Conference on Applied Energy (ICAE), AUG 21-24, 2017, Cardiff, ENGLAND
Tillgänglig från: 2019-01-03 Skapad: 2019-01-03 Senast uppdaterad: 2019-01-16Bibliografiskt granskad
Dahlquist, E., Naqvi, M., Thorin, E., Yan, J. & Kyprianidis, K. (2017). Comparison of Gas Quality from Black Liquor and Wood Pellet Gasification Using Modelica Simulation and Pilot Plant Results. Paper presented at 8th International Conference on Applied Energy, ICAE 2016, 8 October 2016 through 11 October 2016. Energy Procedia, 105, 992-998
Öppna denna publikation i ny flik eller fönster >>Comparison of Gas Quality from Black Liquor and Wood Pellet Gasification Using Modelica Simulation and Pilot Plant Results
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2017 (Engelska)Ingår i: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 105, s. 992-998Artikel i tidskrift (Refereegranskat) Published
Abstract [en]

There is a potential to integrate biomass gasification with pulp & paper and CHP plants in order to complement the existing systems with production of chemicals, such as methane, hydrogen, and methanol etc. To perform system analysis of such integration, it is important to gain knowledge of relevant input data on expected synthesis gas composition by gasifying different types of feed stock. In this paper, the synthesis gas quality from wood pellets gasification (WPG) has been compared with black liquor gasification (BLG) through modeling and experimental results at pilot scale. In addition, the study develops regression models like Partial Least Squares (PLS) made from the experimental data. The regression models are then combined with dynamic models developed in Modelica for the investigation of dynamic energy and material balances for integrated plants. The data presented in this study could be used as input to relevant analysis using e.g. ASPEN plus and similar system analysis tools. 

Ort, förlag, år, upplaga, sidor
Elsevier Ltd, 2017
Nationell ämneskategori
Energiteknik
Identifikatorer
urn:nbn:se:mdh:diva-35989 (URN)10.1016/j.egypro.2017.03.437 (DOI)000404967901014 ()2-s2.0-85020716474 (Scopus ID)
Konferens
8th International Conference on Applied Energy, ICAE 2016, 8 October 2016 through 11 October 2016
Tillgänglig från: 2017-06-29 Skapad: 2017-06-29 Senast uppdaterad: 2018-07-25Bibliografiskt granskad
Organisationer
Identifikatorer
ORCID-id: ORCID iD iconorcid.org/0000-0002-4359-2232

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