Waste to Fuels and Chemicals: Toward a Clean, Green, and Sustainable World

A special issue of Fuels (ISSN 2673-3994).

Deadline for manuscript submissions: closed (15 November 2024) | Viewed by 23274

Special Issue Editor


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Guest Editor
Department of Environmental Research, Korea Institute of Civil Engineering and Building Technology, 283, Goyang-daero, Ilsanseo-gu, Goyang-si 10223, Gyeonggi-do, Korea
Interests: biochar; waste to fuel; risk assessment; pyrolysis

Special Issue Information

Dear Colleagues,

We would like to invite original research or review articles for a Special Issue of Fuels: "Waste to Fuels and Chemicals: Toward a Clean, Green, Sustainable World". With the increasing generation of waste, the idea of turning "Waste into fuels and chemicals" has emerged. The conversion of waste into fuels and/or chemicals requires innovative, environmental, and economical solutions.

In this Special Issue, we aim to share various perspectives on waste treatment, alternative resources, renewable energy, sustainability, and green chemistry. The research scope of this issue is not limited to a single sector but encompasses various experimental attempts to convert waste into fuels and chemicals, reduce greenhouse gas emissions, and develop alternative resources.

Dr. Yoonah Jeong
Guest Editor

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Keywords

  • sustainability
  • fuels
  • chemicals
  • biomass
  • bioenergy

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Published Papers (6 papers)

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Research

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19 pages, 1960 KiB  
Article
Performance of An Energy Production System Consisting of Solar Collector, Biogas Dry Reforming Reactor and Solid Oxide Fuel Cell
by Akira Nishimura, Ryotaro Sato and Eric Hu
Fuels 2024, 5(3), 278-296; https://doi.org/10.3390/fuels5030016 - 10 Jul 2024
Viewed by 667
Abstract
This paper aims to study the performance of solar collectors of various sizes under different weather conditions in different Japanese cities, i.e., Kofu City, Nagoya City and Yamagata City. The heat generated by the solar collector was used to conduct a biogas dry [...] Read more.
This paper aims to study the performance of solar collectors of various sizes under different weather conditions in different Japanese cities, i.e., Kofu City, Nagoya City and Yamagata City. The heat generated by the solar collector was used to conduct a biogas dry reforming reactor for producing H2 to feed a solid oxide fuel cell (SOFC). This study revealed that the output temperature of a solar collector Tfb in April and July was higher than that in January and October irrespective of city. The optimum length of the absorber (dx) of the collector was 4 m irrespective of city. It was clarified that the Tfb in Yamagata City in January and October, i.e., winter and autumn, is lower than that in Kofu City and especially Nagoya City, which is strongly influenced by the tendency of solar intensity (I), not the velocity of the surrounding air (ua). On the other hand, the Tfb is almost the same in April and July, i.e., spring and summer, irrespective of city. The amount of produced H2 via the biogas dry reforming reactor and the power generated by the SOFC using H2 in spring and summer were higher compared to the other seasons irrespective of city. This study revealed that the highest available household number per month was 4.7, according to the investigation in this study. Full article
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20 pages, 6100 KiB  
Article
Grindability of Torrefied Camelina Straw and Microparticle Evaluation by Confocal Laser Scanning Microscopy for Use as Biofuel
by Obiora S. Agu, Lope G. Tabil, Edmund Mupondwa and Bagher Emadi
Fuels 2024, 5(2), 137-156; https://doi.org/10.3390/fuels5020009 - 11 Apr 2024
Viewed by 1965
Abstract
This study examined the combined effect of torrefaction and microwave absorbers on improving biomass thermochemical characteristics and grindability for heat, power, and value-added products. Camelina straw in two grinds, ground (6.4 mm screen size) and chopped with biochar addition (0%, 10% and 20%), [...] Read more.
This study examined the combined effect of torrefaction and microwave absorbers on improving biomass thermochemical characteristics and grindability for heat, power, and value-added products. Camelina straw in two grinds, ground (6.4 mm screen size) and chopped with biochar addition (0%, 10% and 20%), was torrefied in a bench-scale microwave reactor at torrefaction temperatures of 250 °C and 300 °C with residence times of 10, 15 and 20 min under inert conditions and nitrogen-activated. After torrefaction, the geometric mean particle and size distribution, moisture content, ash content, bulk and particle densities were determined, and the grinding performance values of torrefied ground and chopped with and without biochar were determined and compared with the raw camelina straw. The results showed that the geometric diameter decreased after torrefaction in both grinds. The specific energy required for grinding torrefied biomass decreased significantly with biochar addition, longer residence times, and increased torrefaction temperatures. Torrefied ground camelina straw with biochar after grinding had the lowest grinding energy of 34.30 kJ at 300 °C/20 min. The surface morphology by confocal laser scanning microscopy of torrefied camelina straw particles indicated that biochar addition (>10%) and a torrefaction temperature at 250 °C can create profound surface distortion, and beyond 300 °C, colossal surface damage and carbonized weight fractions were produced. Full article
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22 pages, 2911 KiB  
Article
Influence of Transesterification Catalysts Synthesized with Citric Acid on the Quality and Oxidative Stability of Biodiesel from Black Soldier Fly Larvae
by Lilies K. Kathumbi, Patrick G. Home, James M. Raude, Benson B. Gathitu, Anthony N. Gachanja, Anthony Wamalwa and Geoffrey Mibei
Fuels 2022, 3(3), 533-554; https://doi.org/10.3390/fuels3030032 - 2 Sep 2022
Cited by 2 | Viewed by 2296
Abstract
In biodegradable waste management, use of Black Soldier Fly Larvae (BSFL) is a promising method for bioconversion of waste into crude insect fat as feedstock for biodiesel production. Biodiesel is a renewable alternative to fossil fuel, but it is more susceptible to oxidative [...] Read more.
In biodegradable waste management, use of Black Soldier Fly Larvae (BSFL) is a promising method for bioconversion of waste into crude insect fat as feedstock for biodiesel production. Biodiesel is a renewable alternative to fossil fuel, but it is more susceptible to oxidative degradation over long-term storage. This study investigates the effectiveness of NaOH and CaO catalysts synthesized with citric acid (CA) in improving the oxidative stability of biodiesel. The biodiesel and biodiesel/diesel blends derived from BSFL were stored at 63 °C for 8 days. The quality of biodiesel was determined by analysis of the physicochemical and fuel properties by: Fourier transform infrared (FTIR) spectroscopy, ultraviolet visible spectrophotometer (UV-Vis), gas chromatography-mass spectroscopy (GC-MS), bomb calorimeter and titration methods. Properties that were analyzed included: peroxide value, acid value, iodine value, refractive index, density, calorific value, total oxidation (TOTOX), anisidine value and fatty acid profile. The results showed that catalysts synthesized with CA retarded the decomposition of unsaturated fatty acids, resulting in a significant delay in the formation of hydroperoxides. Besides, 10-oxo-octadecanoic acid, an antioxidant, was present in biodiesel produced using catalysts synthesized with CA, hence enhancing the stability of biodiesel against oxidation. Catalysts synthesized with CA slowed the decomposition of monounsaturated fatty acids by 6.11–11.25%. Overall, biodiesel produced using catalysts synthesized with CA was observed to degrade at a slower rate than biodiesel produced using commercial calcium oxide. The reduced degradation rates demonstrate the effectiveness of the synthesized catalysts in enhancing the oxidation stability and consequently the fuel qualities of biodiesel from BSFL under accelerated storage. Full article
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17 pages, 26780 KiB  
Article
Natural Gas Conversion and Organic Waste Gasification by Detonation-Born Ultra-Superheated Steam: Effect of Reactor Volume
by Sergey M. Frolov, Viktor A. Smetanyuk, Ilias A. Sadykov, Anton S. Silantiev, Igor O. Shamshin, Viktor S. Aksenov, Konstantin A. Avdeev and Fedor S. Frolov
Fuels 2022, 3(3), 375-391; https://doi.org/10.3390/fuels3030024 - 24 Jun 2022
Cited by 4 | Viewed by 2517
Abstract
The pulsed detonation (PD) gun technology was applied for the autothermal high-temperature conversion of natural gas and atmospheric-pressure oxygen-free allothermal gasification of liquid/solid organic wastes by detonation-born ultra-superheated steam (USS) using two flow reactors of essentially different volume: 100 and 40 dm3 [...] Read more.
The pulsed detonation (PD) gun technology was applied for the autothermal high-temperature conversion of natural gas and atmospheric-pressure oxygen-free allothermal gasification of liquid/solid organic wastes by detonation-born ultra-superheated steam (USS) using two flow reactors of essentially different volume: 100 and 40 dm3. Liquid and solid wastes were waste machine oil and wood sawdust, with moisture ranging from 10 to 30%wt. It was expected that decrease in the reactor volume from 100 to 40 dm3, other conditions being equal, on the one hand, should not affect natural gas conversion but, on the other hand, could lead to an increase in the gasification temperature in the flow reactor and, correspondingly, to an increase in the product syngas (H2 + CO) quality. The PD gun was fed by natural gas–oxygen mixture and operated at a frequency of 1 Hz. As was expected, complete conversion of natural gas to product syngas in the PD gun was obtained with H2/CO and CO2/CO ratios equal to 1.25 and 0.25, irrespective of the reactor volume. Liquid and solid wastes were gasified to H2, CO, and CH4 in the flow reactors. The steady-state H2/CO and CO2/CO ratios in the syngas produced from waste machine oil were 0.8 and 0.5 for the 100-dm3 reactor and 0.9 and 0.2 for the 40-dm3 reactor, respectively, thus indicating the expected improvement in syngas quality. Moreover, the maximum mass flow rate of feedstock in the 40-dm3 reactor was increased by a factor of over 4 as compared to the 100-dm3 reactor. The steady-state H2/CO and CO2/CO ratios in the syngas produced from the fixed weight (2 kg) batch of wood sawdust were 0.5 and 0.8 for both reactors, and the gasification time in both reactors was about 5–7 min. The measured H2 vs. CO2 and CO vs. CO2 dependences for the syngas produced by the autothermal high-temperature conversion of natural gas and atmospheric-pressure allothermal gasification of liquid/solid organic wastes by USS at f = 1 Hz were shown to be almost independent of the feedstock and reactor volume due to high values of local instantaneous gasification temperature. Full article
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21 pages, 5322 KiB  
Article
Performance of Citric Acid as a Catalyst and Support Catalyst When Synthesized with NaOH and CaO in Transesterification of Biodiesel from Black Soldier Fly Larvae Fed on Kitchen Waste
by Lilies K. Kathumbi, Patrick G. Home, James M. Raude and Benson B. Gathitu
Fuels 2022, 3(2), 295-315; https://doi.org/10.3390/fuels3020018 - 17 May 2022
Cited by 4 | Viewed by 3693
Abstract
Current research and development to lower the production cost of biodiesel by utilizing feedstock derived from waste motivates the quest for developing catalysts with high performance in transesterification. This study investigates the performance of citric acid as a catalyst and support catalyst in [...] Read more.
Current research and development to lower the production cost of biodiesel by utilizing feedstock derived from waste motivates the quest for developing catalysts with high performance in transesterification. This study investigates the performance of citric acid as a catalyst and support catalyst in transesterification of oil from black soldier fly (Hermetia illucens) larvae fed on organic kitchen waste. Two catalysts were prepared by synthesizing citric acid with NaOH and CaO by a co-precipitation and an impregnation method, respectively. The design of the experiment adopted response surface methodology for the optimization of biodiesel productivity by varying: the percentage loading weight of citric acid, the impregnation temperature, the calcinating temperature and the calcinating time. The characteristic activity and reuse of the synthesized catalysts in transesterification reactions were investigated. The morphology, chemical composition and structure of the catalysts were characterized by scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, X-ray fluorescence (XRF) and X-ray diffraction (XRD). High citric acid loading on NaOH and a small amount of citric acid on CaO resulted in improved dispersion and refinement of the particle sizes. Increasing citric acid loading on NaOH improved the CaO and SiO2 composition of the modified catalyst resulting in higher biodiesel yield compared to the modified CaO catalyst. A maximum biodiesel yield of 93.08%, ±1.31, was obtained when NaOH was synthesized with a 130% weight of citric acid at 80 °C and calcinated at 600 °C for 240 min. Comparatively, a maximum biodiesel yield of 90.35%, ±1.99, was obtained when CaO was synthesized with a 3% weight of citric acid, impregnated at 140 °C and calcinated at 900 °C for 240 min. The two modified catalysts could be recycled four times while maintaining a biodiesel yield of more than 70%. Full article
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Review

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19 pages, 3070 KiB  
Review
Biofuels Production: A Review on Sustainable Alternatives to Traditional Fuels and Energy Sources
by Kamla Malik, Sergio C. Capareda, Baldev Raj Kamboj, Shweta Malik, Karmal Singh, Sandeep Arya and Dalip Kumar Bishnoi
Fuels 2024, 5(2), 157-175; https://doi.org/10.3390/fuels5020010 - 2 May 2024
Cited by 17 | Viewed by 11017
Abstract
With increased worldwide energy demand and carbon dioxide emissions from the use of fossil fuels, severe problems are being experienced in modern times. Energy is one of the most important resources for humankind, and its needs have been drastically increasing due to energy [...] Read more.
With increased worldwide energy demand and carbon dioxide emissions from the use of fossil fuels, severe problems are being experienced in modern times. Energy is one of the most important resources for humankind, and its needs have been drastically increasing due to energy consumption, the rapid depletion of fossil fuels, and environmental crises. Therefore, it is important to identify and search for an alternative to fossil fuels that provides energy in a reliable, constant, and sustainable way that could use available energy sources efficiently for alternative renewable sources of fuel that are clean, non-toxic, and eco-friendly. In this way, there is a dire need to develop technologies for biofuel production with a focus on economic feasibility, sustainability, and renewability. Several technologies, such as biological and thermochemical approaches, are derived from abundant renewable biological sources, such as biomass and agricultural waste, using advanced conversion technologies for biofuel production. Biofuels are non-toxic, biodegradable, and recognized as an important sustainable greener energy source to conventional fossil fuels with lower carbon emissions, combat air pollution, empower rural communities, and increase economic growth and energy supply. The purpose of this review is to explain the basic aspects of biofuels and their sustainability criteria, with a particular focus on conversion technologies for biofuel production, challenges, and future perspectives. Full article
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