| 1. |
- Han, Tong, et al.
(författare)
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Magnetic bio-activated carbon production from lignin via a streamlined process and its use in phosphate removal from aqueous solutions
- 2020
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Ingår i: Science of the Total Environment. - : Elsevier. - 0048-9697 .- 1879-1026. ; 708
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Tidskriftsartikel (refereegranskat)abstract
- Lignin and ferrous salt were mechanically mixed, melted, carbonized and steam activated to produce magnetic bio-activated carbons (MBACs). Phosphate adsorption capacity measurement was conducted on representative MBAC, which has a high surface iron oxide proportion and mesoporous volume. The results indicate that iron species are embedded into the carbon matrix by lignin melting. Steam is not only an activation agent for pore generation and widening but is also effective for the oxidization of Hagg iron carbide produced via ferrous salt decomposition and subsequent reduction during the carbonization process to form magnetite. The porous and magnetic properties and surface iron oxide content of the produced MBACs can be modified by controlling the steam/magnetic biochar (MBC) ratio. The MBAC production process is streamlined and novel, compared with conventional coprecipitation or impregnation methods. The maximum phosphate adsorption onto the representative MBAC product using the best fitting model, i.e., the Langmuir-Freundlich model, is estimated to be 21.18 mg/g, suggesting that the representative MBAC product has a comparable phosphate adsorption capacity to most of the reported MBCs and MBACs.
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| 2. |
- Jin, Yanghao, et al.
(författare)
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A novel three-stage ex-situ catalytic pyrolysis process for improved bio-oil yield and quality from lignocellulosic biomass
- 2024
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Ingår i: Energy. - : Elsevier Ltd. - 0360-5442 .- 1873-6785. ; 295
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Tidskriftsartikel (refereegranskat)abstract
- This study aims to improve the quality and yield of bio-oil produced from ex-situ catalytic pyrolysis of lignocellulosic biomass (sawdust) using a combination of stage catalysts with Al-MCM-41, HZSM-5, and ZrO2. The research employed various methods, including thermogravimetric analysis (TGA), differential scanning calorimetry, bench-scale experiments, and process simulations to analyze the kinetics, thermodynamics, products, and energy flows of the catalytic upgrading process. The introduction of ZrO2 enhances the yield of monoaromatic hydrocarbons (MAHs) in heavy organics. Compared with the dual-catalyst case, the MAHs yield escalates by approximately 344% at a catalyst ratio of 1:3:0.25. Additionally, GC-MS data indicate that the incorporation of ZrO2 promotes the deoxygenation reaction of the guaiacol compound and the oligomerization reactions of PAHs. The integration of ZrO2 as the third catalyst enhances the yield of heavy organics significantly, achieving 16.85% at a catalyst ratio of 1:3:1, which increases by nearly 35.6% compared to the dual-catalyst case. Also, the addition of ZrO2 as the third catalyst enhanced the energy distribution in heavy organics. These findings suggest that the combination of these catalysts improves the fuel properties and yields of the bio-oil.
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| 3. |
- Kang, Yanlei, et al.
(författare)
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AFTGAN : prediction of multi-type PPI based on attention free transformer and graph attention network
- 2023
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Ingår i: Bioinformatics. - : Oxford University Press (OUP). - 1367-4803 .- 1367-4811. ; 39:2
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Tidskriftsartikel (refereegranskat)abstract
- Motivation: Protein–protein interaction (PPI) networks and transcriptional regulatory networks are critical in regulating cells and their signaling. A thorough understanding of PPIs can provide more insights into cellular physiology at normal and disease states. Although numerous methods have been proposed to predict PPIs, it is still challenging for interaction prediction between unknown proteins. In this study, a novel neural network named AFTGAN was constructed to predict multi-type PPIs. Regarding feature input, ESM-1b embedding containing much biological information for proteins was added as a protein sequence feature besides amino acid co-occurrence similarity and one-hot coding. An ensemble network was also constructed based on a transformer encoder containing an AFT module (performing the weight operation on vital protein sequence feature information) and graph attention network (extracting the relational features of protein pairs) for the part of the network framework.Results: The experimental results showed that the Micro-F1 of the AFTGAN based on three partitioning schemes (BFS, DFS and the random mode) on the SHS27K and SHS148K datasets was 0.685, 0.711 and 0.867, as well as 0.745, 0.819 and 0.920, respectively, all higher than that of other popular methods. In addition, the experimental comparisons confirmed the performance superiority of the proposed model for predicting PPIs of unknown proteins on the STRING dataset.Availability and implementation: The source code is publicly available at https://github.com/1075793472/AFTGAN.Supplementary information: Supplementary data are available at Bioinformatics online.
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| 4. |
- Liu, J. -L, et al.
(författare)
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Preparation of solid carbon product from lignocellulosic materials via high temperature steam pyrolysis
- 2013
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Ingår i: Chemistry and Industry of Forest Products. - 0253-2417. ; 33:6, s. 19-24
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Tidskriftsartikel (refereegranskat)abstract
- The super-high temperature medium with low cost was obtained by the technology of the honeycomb ceramic heat exchanger. The pyrolysis behavior of super-high temperature medium(steam and nitrogen) and their influences on the components of pyrolysis products were investigated in the fixed bed pyrolysis reactor. The research results showed that the technology of super-high temperature steam pyrolysis trends to prepare high value solid carbon materials with low volatile content and large specific surface area by high-temperature steam pyrolysis. The surface area of solid char from willow pyrolysis at 958 K under steam medium is 280 m2/g. The loss of mass ratio under different mediums is about 80% and the yield of solid carbon is 20%-30% using willow and caragana as raw materials. With the increase of pyrolysis medium temperature, the ratio of mass loss is improved and the time of pyrolysis becomes short. At the same of pyrolysis temperature, the rate of mass loss in the steam medium is greater than that in the N2 medium.
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| 5. |
- Liu, J., et al.
(författare)
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Preparation of high heating value gas, high quality bio-oil and added value carbon materials from Caragana pyrolyzed via super-high temperature steam
- 2012
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Ingår i: Advanced Materials Research. - : Trans Tech Publications Inc.. - 9783037854143 ; , s. 2152-2161
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Konferensbidrag (refereegranskat)abstract
- Caragana is an abundant plant as the feedstock of biomass energy in China. In this study, pyrolysis of Caragana in the presence of high temperature medium and characterization of products has been carried out. Evaluation of experimental results showed that faster devolatilization and char with increased surface area obtained in the presence of high temperature steam comparing to N 2. Analysis of the obtained liquid revealed that the H/C and O/C ratios in the liquid are 1.5 and 0.16 respectively. Further more gas composition during high temperature steam pyrolysis differs from gas composition derived from N 2 pyrolysis which indicates interaction of steam with vapors and solid species even at low treatment temperatures. The derived products' yields and characteristics indicate possible exploitation of derived char as activate carbon precursor. Liquid fraction composition makes it suitable for exploitation as liquid fuel and/or chemical feedstock.
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| 6. |
- Liu, J., et al.
(författare)
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Sustainable exploitation of salix via high temperature steam pyrolysis for energy production and added value materials
- 2013
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Ingår i: ICMREE 2013 - Proceedings: 2013 International Conference on Materials for Renewable Energy and Environment. ; , s. 249-255
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Konferensbidrag (refereegranskat)abstract
- Salix is an abundant plant as the feedstock of biomass energy in many countries all over the world. It has an extremely rapid growing rate, and it can be considered as a sustainable raw material wood resource. In this study pyrolysis of salix in the presence inert atmosphere (N2) and high temperature steam (which combines the benefits of High Temperature Steam Gasification (HTSG) and steam pyrolysis) and characterization of products has been carried out. Evaluation of experimental results showed that faster devolatilization and char with increased surface area obtained in the presence of high temperature steam comparing to N2 while higher liquid production obtained at 823 K in the presence of high temperature steam. Analysis of the obtained liquid revealed that the H/C and O/C ratios in the liquid are 1.5 and 0.16 respectively. Further more gas composition during high temperature steam pyrolysis differs from gas composition derived from N2 pyrolysis which indicates interaction of steam with vapors and solid species even at low treatment temperatures. The derived products’ yields and characteristics indicate possible exploitation of derived char as activate carbon precursor or reducing agent in metallurgical processes or solid fuel for gasification and combustion processes. Liquid fraction composition makes it suitable for exploitation as liquid fuel and/or chemical feedstock.
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| 7. |
- Lu, Xincheng, et al.
(författare)
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Comprehensive insights into the influences of acid-base properties of chemical pretreatment reagents on biomass pyrolysis behavior and wood vinegar properties
- 2020
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Ingår i: Journal of Analytical and Applied Pyrolysis. - : Elsevier BV. - 0165-2370 .- 1873-250X. ; 151
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Tidskriftsartikel (refereegranskat)abstract
- Pyrolysis of biomass is an effective approach to produce high-value added solid, liquid and gaseous products. Wood vinegar (WV) is obtained as one of the main liquid products of biomass pyrolysis and has been used as the sustainable chemicals in agriculture. In this study, the effects of acid-base properties of chemical reagents on the biomass pyrolysis behavior and WV properties were investigated, and the mechanism was further discussed. The results indicated that acid-base properties of chemical reagents exhibited the significant effects on pyrolysis behavior and WV properties. Alkaline compounds showed the more obviously effects on changes in biomass chemical structure rather than acids, while acids removed the metallic species more efficiently than alkaline compounds. All chemical pretreatments increased the cellulose crystallinity, and the alkaline compounds were more favorable than the acidic compounds for increasing the crystallinity. Meanwhile, chemical pretreatments changed the chemical structure of biomass and promoted the pyrolysis process. All chemical pretreatments increased the organic content of WV. The relative content of phenols increased after all pretreatments, which increased more obviously by the acids pretreatments. Whereas, the relative content of acids decreased after pretreated by inorganic acids, and increased after pretreated by organic acids and alkaline compounds.
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| 8. |
- Lu, Xincheng, et al.
(författare)
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Enhanced antioxidant activity of aqueous phase bio-oil by hydrothermal pretreatment and its structure-activity relationship
- 2021
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Ingår i: Journal of Analytical and Applied Pyrolysis. - : Elsevier BV. - 0165-2370 .- 1873-250X. ; 153
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Tidskriftsartikel (refereegranskat)abstract
- The antioxidant activity and the structure-activity relationship of aqueous phase bio-oil (APBO), obtained from hydrothermal treatment (HTT) combined with pyrolysis of biomass, have been investigated in this study. HTT increased the relative content of phenolic compounds and reduced the relative content of acids. Phenolic compounds possessed as the dominant chemical components in APBO, representing up to 61.68 %. 2-methoxyphenol (guaiacol) and its derivatives were the major components of phenolic compounds. HTT promoted the antioxidant activity of APBOs and APBO-180 showed higher antioxidant activity than that of commercial chemical antioxidant (butylated hydroxyl toluene) with IC50 values of 0.402 mg/mL of reducing power, 0.132 mg/mL of DPPH free radical scavenging capacity and 0.405 mg/mL of hydroxyl free radical scavenging capability. The antioxidant activity of APBO was affected by its chemical composition. Phenols exhibited a promotion effect on antioxidant activity, while acids showed an inhibition effect. In addition, the substituent structure of phenols played a key role in antioxidant activity. Phenols with the shorter carbon side chain showed higher antioxidant activity (e.g. 2-methylphenol>2-methoxyphenol, 4-methyl-2-methoxyphenol>4-ethyl-2methoxyphenol). This study suggested that APBO could be developed as the natural feed additives or alternative antioxidant, providing a new strategy for efficient utilization of APBO.
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| 9. |
- Sun, Yunjuan, et al.
(författare)
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Development of a bimetallic dolomite based tar cracking catalyst
- 2012
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Ingår i: Catalysis communications. - : Elsevier BV. - 1566-7367 .- 1873-3905. ; 20, s. 36-40
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Tidskriftsartikel (refereegranskat)abstract
- In this study a bimetallic dolomite based tar cracking catalyst was developed and tested. It was enriched in Ni and Fe with BET surface area of 12.31 m(2)/g. The catalytic characterizations were tested with tar simulated by naphthalene, and with tar produced by biomass and coal co-pyrolysis. 93% naphthalene was decomposed at 950 degrees C. A first order apparent kinetic model was developed. Activation energy of 63.96 kJ/mol and pre-exponential factor of 396.2/s were calculated. Furthermore, reduction in char yield by 7%, when the catalyst was used in the biomass-coal co-pyrolysis, was observed.
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| 10. |
- Wang, Shule, 1994-, et al.
(författare)
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Renewable hydrogen production from the organic fraction of municipal solid waste through a novel carbon-negative process concept
- 2022
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Ingår i: Energy. - : Elsevier BV. - 0360-5442 .- 1873-6785. ; 252
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Tidskriftsartikel (refereegranskat)abstract
- Bioenergy with carbon capture and storage (BECCS) is one of the prevailing negative carbon emission technologies. Ensuring a hydrogen economy is essential to achieving the carbon-neutral goal. In this regard, the present study contributed by proposing a carbon negative process for producing high purity hydrogen from the organic fraction of municipal solid waste (OFMSW). This integrated process comprises anaerobic digestion, pyrolysis, catalytic reforming, water-gas shift, and pressure swing adsorption technologies. By focusing on Sweden, the proposed process was developed and evaluated through sensitivity analysis, mass and energy balance calculations, techno-economic assessment, and practical feasibility analysis. By employing the optimum operating conditions from the sensitivity analysis, 72.2 kg H2 and 701.47 kg negative CO2 equivalent emissions were obtained by treating 1 ton of dry OFMSW. To achieve these results, 6621.4 MJ electricity and 325 kg of steam were utilized during this process. Based on this techno-economic assessment of implementing the proposed process in Stockholm, when the negative CO2 equivalent emissions are recognized as income, the internal rate of return and the discounted payback period can be obtained as 26% and 4.3 years, respectively. Otherwise, these values will be 13% and 7.2 years.
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