Carbon tax-driven technological innovation may accelerate the directional recovery of waste cooking oil into bio-jet fuel: An evolutionary game approach.

Biofuel production from waste cooking oil (WCO) offers an alternative to fossil fuels, especially for high-value bio-jet fuel. However, this industry is hindered by informal recyclers who covertly divert large amounts of WCO to illegal gutter oil production. Investigating the dynamic evolution of stakeholder behavior will help explore solutions. Thus, this study presents a tripartite evolutionary game model that includes the government, formal recyclers, and informal recyclers, aims to redesign the government intervention strategy to promote the directional flow of WCO from restaurant trash cans to bio-jet fuel production. We find that the evolutionary game model exists eight possible evolutionary stability strategies (ESSs), and the choice of each ESS depends mainly on the trade-off between costs and revenues for each stakeholder. The numerical study results reveal that formal recyclers are driven to carry out technological innovation by government support, profiting from bio-aviation kerosene products, and income from carbon emission reduction. These factors also have an indirect impact on the transformation of informal recyclers. Therefore, the government should provide adequate support for technological innovation to formal recyclers and increase their profitability of products to enable them to actively implement innovative strategies. This can be achieved by expanding the sales channels of bio-jet fuel products, implementing patent protection measures, and improving the carbon reduction trading mechanism. Furthermore, the government's high tax rate on formal recyclers and the significant profits earned by informal recyclers through illegal gutter oil production may dissuade them from transitioning their businesses. Above findings are in line with the actual issues of WCO recycling and provide a new dynamic decision-making method for enterprises and government managers.

Wastewater-grown microalgae biomass as a source of sustainable aviation fuel: Life cycle assessment comparing hydrothermal routes.

The present paper compared, through life cycle assessment (LCA), the production of aviation biofuel from two hydrothermal routes of microalgae cultivated in wastewater. Hydrothermal liquefaction (HTL) and gasification followed by Fischer-Tropsch synthesis (G + FT) were compared. Both routes included biomass production, hydrotreatment for biofuel upgrading, and product fractionation. Secondary data obtained from the literature were used for the cradle-to-gate LCA. G + FT had a higher impact than HTL in the 18 impact categories assessed, with human carcinogenic toxicity exerting the most harmful pressure on the environment. The catalysts were the inputs that caused the most adverse emissions. The solvent used for bio-oil separation also stood out in terms of impacts. In HTL, emissions for global warming were -51.6 g CO2 eq/MJ, while in G + FT, they were 250 g CO2 eq/MJ. At the Endpoint level, HTL resulted in benefits to human health and ecosystems, while G + FT caused environmental damage in these two categories, as well as in the resources category. In the improvement scenarios, besides considering solid, aqueous, and gaseous products as co-products rather than just as waste/emissions, a 20% reduction in catalyst consumption and 90% recovery were applied. Thus, in HTL, 39.47 kg CO2 eq was avoided, compared to 35.44 kg CO2 eq in the base scenario. In G + FT, emissions decreased from 147.55 kg CO2 eq to the capture of 8.60 kg CO2 eq.

Aviation fuel based on wastewater-grown microalgae: Challenges and opportunities of hydrothermal liquefaction and hydrotreatment.

The current technical issues related to the conversion of algal biomass into aviation biofuel through hydrothermal liquefaction (HTL) and the upgrading of bio-oil through hydrotreatment have been reviewed and consolidated. HTL is a promising route for converting microalgae into sustainable aviation fuel (SAF). However, HTL must be followed by the hydrotreatment of bio-oil to ensure that its composition and properties are compatible with SAF standards. The fact that microalgae offer the possibility of recovering wastewater treatment resources not only makes them more attractive but also serves as an incentive for wastewater treatment, especially in countries where this service has not been universalized. The combination of SAF and wastewater treatment aligns with the Sustainable Development Goals of the United Nations, representing an advantageous opportunity for both aviation and sanitation. In this context, the utilization of HTL by-products in the concept of a biorefinery is essential for the sustainability of aviation biofuel production through this route. Another important aspect is the recovery and reuse of catalysts, which are generally heterogeneous, allowing for recycling. Additionally, discussions have focused on biomass pretreatment methods, the use of solvents and catalysts in HTL and hydrotreatment reactions, and the operational parameters of both processes. All these issues present opportunities to enhance the quantity and quality of bio-oil and aviation biofuel.

Bifunctional MoS2/Al2O3-Zeolite Catalysts in the Hydroprocessing of Methyl Palmitate.

A series of bifunctional catalysts, MoS2/Al2O3 (70 wt.%), zeolite (30 wt.%) (zeolite-ZSM-5, ZSM-12, and ZSM-22), and silica aluminophosphate SAPO-11, were synthesized for hydroconversion of methyl palmitate (10 wt.% in dodecane) in a trickle-bed reactor. Mo loading was about 7 wt.%. Catalysts and supports were characterized by different physical-chemical methods (HRTEM-EDX, SEM-EDX, XRD, N2 physisorption, and FTIR spectroscopy). Hydroprocessing was performed at a temperature of 250-350 °C, hydrogen pressure of 3.0-5.0 MPa, liquid hourly space velocity (LHSV) of 36 h-1, and an H2/feed ratio of 600 Nm3/m3. Complete conversion of oxygen-containing compounds was achieved at 310 °C in the presence of MoS2/Al2O3-zeolite catalysts; the selectivity for the conversion of methyl palmitate via the 'direct' hydrodeoxygenation (HDO) route was over 85%. The yield of iso-alkanes gradually increases in order: MoS2/Al2O3 < MoS2/Al2O3-ZSM-12 < MoS2/Al2O3-ZSM-5 < MoS2/Al2O3-SAPO-11 < MoS2/Al2O3-ZSM-22. The sample MoS2/Al2O3-ZSM-22 demonstrated the highest yield of iso-alkanes (40%). The hydroisomerization activity of the catalysts was in good correlation with the concentration of Brønsted acid sites in the synthesized supports.

Behavior of deteriogenic fungi in aviation fuels (fossil and biofuel) during simulated storage.

Biofuels are expected to play a major role in reducing carbon emissions in the aviation sector globally. Farnesane ("2,6,10-trimethyldodecane") is a biofuel derived from the synthesized iso-paraffin route wich can be blended with jet fuel; however, the microbial behavior in farnesane/jet fuel blends remains unknown. The chemical and biological stability of blends should be investigated to ensure they meet the quality requirements for aviation fuels. This work aimed at evaluating the behavior of two fungi Hormoconis resinae (F089) and Exophiala phaeomuriformis (UFRGS Q4.2) in jet fuel, farnesane, and in 10% farnesane blend during simulated storage. Microcosms (150-mL flasks) were assembled with and without fungi containing Bushnell & Haas mineral medium for 28 days at a temperature of 20±2°C. The fungal growth (biomass), pH, surface tension, and changes in the fuel's hydrocarbon chains were evaluated. This study revealed thatthe treatment containing H. resinae showed a biomass of 19 mg, 12 mg, and 2 mg for jet fuel, blend, and farnesane respectively. The pH was reduced from 7.2 to 4.3 observed in jet fuel treatment The degradation results showed that compounds with carbon chains between C9 and C11, in jet fuel, and blend treatments were preferably degraded. The highest biomass (70.9 mg) produced by E. phaeomuriformis was in 10% farnesane blend, after 21 days. However, no significant decrease was observed on pH and surface tension measurements across the treatments as well as on the hydrocarbons when compared to the controls. This study revealed that farnesane neither inhibited nor promoted greater growth on both microorganisms.

Superior detection of significant prostate cancer by transperineal prostate biopsy using MRI-transrectal ultrasound fusion image guidance over cognitive registration.

BACKGROUND: The BioJet system allows the fusion of magnetic resonance imaging (MRI) images with real-time transrectal ultrasonography to accurately direct biopsy needles to the target lesions. To date, the superiority of targeted biopsy using the BioJet system over cognitive registration remains unknown. METHODS: This retrospective study included 171 biopsy-naïve men with elevated prostate-specific antigen (2.5-20 ng/mL) and MRI-positive lesions; 74 and 97 men underwent a four-core targeted biopsy per MRI-positive target lesion and a 14-core systematic biopsy transperineally using the BioJet system and cognitive registration, respectively. Detection rates of significant cancer, defined as grade group ≥ 2 or maximum cancer length ≥ 5 mm, were compared between the BioJet system and cognitive registration using propensity score matching and a multivariate logistic regression model. RESULTS: After propensity score matching (67 men for each group), the detection rates of significant cancer were significantly higher in the BioJet group than in the cognitive group for both targeted (76% vs. 46%, P = 0.002) and systematic (70% vs. 46%, P = 0.018) biopsy. Multivariate analysis of the entire cohort also showed that the BioJet system was independently associated with significant cancer detection by targeted and systematic biopsy (P < 0.01), along with a higher prostate-specific antigen density and a higher prostate imaging reporting and data system score. CONCLUSIONS: Transperineal prostate biopsy using the BioJet system is superior to cognitive registration in detecting significant cancer for targeted and systematic biopsies.

Preparation of bio-jet fuels by a controllable integration process: Coupling of biomass fermentation and olefin polymerization.

This work demonstrated that bio-jet fuels can be directionally prepared from bagasse (a typical lignocellulose biomass) by integrating bio- and chemical catalysis reaction processes. This controllable transformation started with the preparation of acetone/butanol/ethanol (ABE) intermediates through the enzymolysis and fermentation of bagasse. Pretreatment of bagasse by deep eutectic solvent (DES) promoted the enzymatic hydrolysis and fermentation because it destroyed the structure of biomass and remove lignin in lignocellulose. Subsequently, the selective catalytic conversion of sugarcane derived ABE broth to jet range fuels was achieved through an integrated process: ABE dehydration to light olefins over the HSAPO-34 catalyst and olefin polymerization to bio-jet fuels over the Ni/HBET catalyst. The dual catalyst bed synthesis mode improved the selectively of bio-jet fuels. High selectivity of jet range fuels (83.0 %) and high conversion of ABE (95.3 %) were obtained by the integrated process.

Solvent extraction and characterization of Brassica carinata oils as promising alternative feedstock for bio-jet fuel production.

As a fossil fuel substitute, bio-jet fuel derived from inedible oilseed crops has the potential to improve energy security, decrease carbon footprint, and promote agricultural economy and social development. The efficient production of bio-jet fuels depends on the identification and characterization of eco-friendly and sustainable feedstocks. Brassica carinata (Arun Braun) cultivars are among the most significant industrial oilseeds that can be utilized as alternative feedstocks in the aviation industry. The study thoroughly evaluated four non-food Brassica carinata cultivars that are indigenous to Ethiopia to determine their suitability as substitute feedstocks for the production of bio-jet fuel. The effects of solvent extraction parameters were studied using response surface methodology with Box-Behnken design in an isothermal batch reactor. Physicochemical characterization, fatty acids profiling, ultimate analysis, analysis of metals and phosphorus concentration, Fourier-transform infrared spectroscopy characterization, and calorific value analyses were performed to characterize the properties of oils. Accordingly, oil yields ranged from 35.93 to 45.25%. Erucic acid (EA) was the most predominant fatty acid in all oils, accounting for 42-50%, of Derash and Yellow Dodolla oils, respectively, making Yellow Dodolla oil a super-high erucic acid oil. In comparison to the other oils, Yellow Dodolla was observed to be the least oxygenated oil, with a 7.80% oxygen content and oxygen to carbon ratio of 0.07, which may enable it to consume a very limited amount of hydrogen gas during hydrodeoxygenation in bio-jet fuel production. It was determined that, except for calcium and phosphorous levels in Tesfa, the concentrations of the metals and phosphorous were very small. Alkanes, alkenes, carboxylic acids, esters, alcohols, aromatics, and olefins were among the most significant and main functional groups identified. Our extraction and characterization results revealed that the Brassica carinata cultivars have very high oil contents, better physicochemical properties, excellent fatty acid profiles, and very low concentrations of heteroatoms (nitrogen, sulfur), metals and phosphorous concentrations, and very low level of oxygen to carbon ratios, making the oils, notably Yellow Dodolla oil, very high quality and promising alternative feedstocks for upgrading of the oils into bio-jet fuels through hydroprocessing pathway.

Porous Biochar Supported Transition Metal Phosphide Catalysts for Hydrocracking of Palm Oil to Bio-Jet Fuel.

The upgrading of plant-based oils to liquid transportation fuels through the hydrotreating process has become the most attractive and promising technical pathway for producing biofuels. This work produced bio-jet fuel (C9-C14 hydrocarbons) from palm olein oil through hydrocracking over varied metal phosphide supported on porous biochar catalysts. Relative metal phosphide catalysts were investigated for the highest performance for bio-jet fuel production. The palm oil's fiber-derived porous biochar (PFC) revealed its high potential as a catalyst supporter. A series of PFC-supported cobalt, nickel, iron, and molybdenum metal phosphides (Co-P/PFC, Ni-P/PFC, Fe-P/PFC, and Mo-P/PFC) catalysts with a metal-loading content of 10 wt.% were synthesized by wet-impregnation and a reduction process. The performance of the prepared catalysts was tested for palm oil hydrocracking in a trickle-bed continuous flow reactor under fixed conditions; a reaction temperature of 420 °C, LHSV of 1 h-1, and H2 pressure of 50 bar was found. The Fe-P/PFC catalyst represented the highest hydrocracking performance based on 100% conversion with 94.6% bio-jet selectivity due to its higher active phase dispersion along with high acidity, which is higher than other synthesized catalysts. Moreover, the Fe-P/PFC catalyst was found to be the most selective to C9 (35.4%) and C10 (37.6%) hydrocarbons.

Biosynthesis of alkanes/alkenes from fatty acids or derivatives (triacylglycerols or fatty aldehydes).

This review summarizes the most relevant advances in the biological transformation of fatty acids (or derivatives) into hydrocarbons to be used as biofuels (biogasoline, green diesel and jet biofuel). Among the used enzymes, the fatty acid decarboxylase from Jeotgalicoccus sp. ATCC 8456 (OleTJE) stands out as a promising enzyme. OleTJE may be coupled in cascade reactions with metalloenzymes or reductases from the Old Yellow Enzymes (OYE) family to perform the hydrogenation of α-olefins into paraffins. The photodecarboxylase from Chlorella variabilis NC64A (CvFAP) is an example of coupling biocatalysis and photocatalysis to produce alkanes. Besides the (photo)decarboxylation of free fatty acids and/or triacyclglycerols to produce alkanes/alkenes, by enzymes has also been employed. The cyanobacterial aldehyde decarbonylase (cAD) from Nostoc punctiforme is an outstanding example of this kind of enzymes used to produce alkanes. Overall, these kinds of enzymes open up new possibilities to the production of biofuels from renewable sources, even if they have many limitations on the current situation. The possibilities of improving enzymes features via immobilization or coimmobilization, as well as the utilization of whole cells haves been also reviewed.

Valorization of CO2 to ß-farnesene in Rhodobacter sphaeroides.

The valorization of CO2 into valuable products is a sustainable strategy to help overcome the climate crisis. In particular, biological conversion is attractive as it can produce long-chain hydrocarbons such as terpenoids. This study reports the high yield of ß-farnesene production from CO2 by expressing heterologous ß-farnesene synthase (FS) into Rhodobacter sphaeroides. To increase the expression of FS, a strong active promoter and a ribosome binding site (RBS) were engineered. Moreover, ß-farnesene production was improved further through the supply of exogenous antioxidants and additional nutrients. Finally, ß-farnesene was produced from CO2 at a titer of 44.53 mg/L and yield of 234.08 mg/g, values that were correspondingly 23 times and 46 times higher than those from the initial production of ß-farnesene. Altogether, the results here suggest that the autotrophic production of ß-farnesene can provide a starting point for achieving a circular carbon economy.

[Development of bio-jet fuel production technology: a review].

Due to the large amount of greenhouse gas emissions and the high dependence on fossil fuels, the sustainable development of aviation industry has attracted worldwide attention. Bio-jet fuel is considered to be a promising alternative to traditional aviation fuel. This article summarizes the representative technological route, development status, opportunities and challenges faced by the development of bio-jet fuel industry. So far, several bio-jet fuel production technologies have been certified by the American Society for Testing and Materials (ASTM). Hydroprocessed esters and fatty acids is currently the most mature process that can be fully commercialized. Considering economic characteristics and technology maturity, Fischer-Tropsch is promising in near term.

MgO-modified activated biochar for biojet fuels from pyrolysis of sawdust on a simple tandem micro-pyrolyzer.

The aim of this work was to study on MgO-modified KOH activated biochar (AC) catalysts, in the pyrolysis of sawdust for the direct production of bio-jet fuels using a tandem micro-pyrolyzer. AC catalysts with various MgO contents (5 to 20 wt%) were synthesized using an impregnation method. The mesopores generated (4 to 18 nm) in the carbon has a great potential in the conversion of oxygenated to jet fuel. The importance of basic nature in the catalysts is demonstrated with the maximum bio-jet fuel yield of 29 % at 10 % MgO. Further, the temperature of 600 °C and a catalyst/sawdust ratio of 10 are identified as the optimal conditions. The nanosize of MgO and the synergism of acid and base sites seemed to enhance deoxygenation, via decarboxylation and decarbonylation, and oligomerization, which are required for jet fuel formation in high amounts from sawdust pyrolysis.

Toward net-zero sustainable aviation fuel with wet waste-derived volatile fatty acids.

With the increasing demand for net-zero sustainable aviation fuels (SAF), new conversion technologies are needed to process waste feedstocks and meet carbon reduction and cost targets. Wet waste is a low-cost, prevalent feedstock with the energy potential to displace over 20% of US jet fuel consumption; however, its complexity and high moisture typically relegates its use to methane production from anaerobic digestion. To overcome this, methanogenesis can be arrested during fermentation to instead produce C2 to C8 volatile fatty acids (VFA) for catalytic upgrading to SAF. Here, we evaluate the catalytic conversion of food waste-derived VFAs to produce n-paraffin SAF for near-term use as a 10 vol% blend for ASTM "Fast Track" qualification and produce a highly branched, isoparaffin VFA-SAF to increase the renewable blend limit. VFA ketonization models assessed the carbon chain length distributions suitable for each VFA-SAF conversion pathway, and food waste-derived VFA ketonization was demonstrated for >100 h of time on stream at approximately theoretical yield. Fuel property blending models and experimental testing determined normal paraffin VFA-SAF meets 10 vol% fuel specifications for "Fast Track." Synergistic blending with isoparaffin VFA-SAF increased the blend limit to 70 vol% by addressing flashpoint and viscosity constraints, with sooting 34% lower than fossil jet. Techno-economic analysis evaluated the major catalytic process cost-drivers, determining the minimum fuel selling price as a function of VFA production costs. Life cycle analysis determined that if food waste is diverted from landfills to avoid methane emissions, VFA-SAF could enable up to 165% reduction in greenhouse gas emissions relative to fossil jet.

Sustainable Production of Microbial Isoprenoid Derived Advanced Biojet Fuels Using Different Generation Feedstocks: A Review.

As the fastest mode of transport, the aircraft is a major driver for globalization and economic growth. The development of alternative advanced liquid fuels is critical to sustainable development within the sector. Such fuels should be compatible with existing infrastructure and derived from second generation feedstocks to avoid competition with food markets. With properties similar to petroleum based fuels, isoprenoid derived compounds such as limonene, bisabolane, farnesane, and pinene dimers are of increasing interest as "drop-in" replacement jet fuels. In this review potential isoprenoid derived jet fuels and progress toward their microbial production was discussed in detail. Although substantial advancements have been achieved, the use of first generation feedstocks remains ubiquitous. Lignocellulosic biomass is the most abundant raw material available for biofuel production, however, technological constraints associated with its pretreatment and saccharification hinder its economic feasibility for low-value commodity production. Non-conventional microbes with novel characteristics including cellulolytic bacteria and fungi capable of highly efficient lignocellulose degradation and xylose fermenting oleaginous yeast with enhanced lignin-associated inhibitor tolerance were investigated as alternatives to traditional model hosts. Finally, innovative bioprocessing methods including consolidated bioprocessing and sequential bioreactor approaches, with potential to capitalize on such unique natural capabilities were considered.

Comparison of Real-Time Virtual Sonography Navigation Versus BioJet Navigation on Magnetic Resonance Imaging-Guided Prostate Needle Biopsy: A Single Institutional Analysis.

Objective: To analyze the effectiveness and complication rate of MRI-guided prostate needle biopsies by using real-time virtual sonography (RVS) vs BioJet navigation. Methods: We retrospectively reviewed 171 patients who underwent an MRI-guided prostate needle biopsy at our institution. Patients whose prostate-specific antigen level was >4.0 ng/mL and who had suspicious prostate cancer (PCa) lesions by multiparametric MRI (mpMRI) underwent 2-core MRI-guided targeted biopsy (TB) and for MRI-guided TB: RVS and BioJet. RVS navigation synchronized mpMRI images with transrectal ultrasound (TRUS) images. BioJet navigation used a software program that merged images from mpMRI and TRUS to produce a composite image. We retrospectively compared the detection rate of PCa and the frequency of severe adverse events (AEs) between these two navigation systems, focusing on patients. In addition, we compared the detection rate of MRI-guided TB cores of two navigation systems regarding anatomical position (transitional zone [TZ] or peripheral zone [PZ]). Results: Data from RVS and BioJet biopsy groups were from 65 and 106 patients, respectively. Of these, RVS-TB included 141 cores (PZ: 49 cores, TZ: 92 cores), and BioJet-TB included 276 cores (PZ: 73 cores, TZ: 203 cores). In detecting PCa, by conducting both systematic biopsy and TB, and AEs in patients, a significant difference was not noted between RVS and BioJet navigation systems. In addition, there was no significant difference in the total detection rate for PCa in TB cores between the two methods. However, in the TZ, BioJet navigation showed a significantly higher detection rate of PCa than RVS navigation (35.0% vs 17.4%, p = 0.0023) by analyzing the cores of MRI-guided TB. Conclusion: When targeting TZ lesions, BioJet navigation had a greater detection rate for PCa compared with that of RVS navigation.

Synthesis and characterization of sulfonated activated carbon as a catalyst for bio-jet fuel production from biomass and waste plastics.

Sulfonated activated carbon-based catalysts were prepared by microwaved-assisted carbonization of phosphoric acid activated corncob followed by sulfonation using concentrated sulfuric acid. Sulfonation at different temperatures and times resulted in varied SO3H group density of the SAC catalysts. Sulfonation temperature showed a significant effect on the introduction of SO3H on the AC precursor while time had minor role. The SAC catalysts were characterized by means of N2 sorption analysis (specific surface area, pore-volume, average pore width), FTIR spectroscopy, SEM imaging, and sulfur analysis. The impact of catalysts SO3H density on the product distribution and bio-oil composition from the catalytic co-pyrolysis of Douglas fir and LDPE was evaluated. The highest bio-jet fuels (aromatics and C9-16 alkanes) obtained was 97.51% using the SAC catalyst sulfonated at 100 °C for 5 h. Results showed that SAC has great potential as catalyst in the co-pyrolysis of biomass and plastics for the production of jet-fuel range hydrocarbons.

Potential yields and emission reductions of biojet fuels produced via hydrotreatment of biocrudes produced through direct thermochemical liquefaction.

BACKGROUND: The hydrotreatment of oleochemical/lipid feedstocks is currently the only technology that provides significant volumes (millions of litres per year) of "conventional" biojet/sustainable aviation fuels (SAF). However, if biojet fuels are to be produced in sustainably sourced volumes (billions of litres per year) at a price comparable with fossil jet fuel, biomass-derived "advanced" biojet fuels will be needed. Three direct thermochemical liquefaction technologies, fast pyrolysis, catalytic fast pyrolysis and hydrothermal liquefaction were assessed for their potential to produce "biocrudes" which were subsequently upgraded to drop-in biofuels by either dedicated hydrotreatment or co-processed hydrotreatment. RESULTS: A significant biojet fraction (between 20.8 and 36.6% of total upgraded fuel volume) was produced by all of the processes. When the fractions were assessed against general ASTM D7566 specifications they showed significant compliance, despite a lack of optimization in any of the process steps. When the life cycle analysis GHGenius model was used to assess the carbon intensity of the various products, significant emission reductions (up to 74%) could be achieved. CONCLUSIONS: It was apparent that the production of biojet fuels based on direct thermochemical liquefaction of biocrudes, followed by hydrotreating, has considerable potential.

Empirical equations and economical study for blending biofuel with petroleum jet fuel.

Distillate of upgraded palm biodiesel was blended in different volume percentages (5, 10, 15, and 20%) with jet A-1. The mixture can be used as a replacement for petroleum Jet fuel. Physical properties of blends were measured and compared with those of jet A-1. Empirical equations were developed to predict the properties of blended fuel, including density, kinematic viscosity, freezing point, H/C ratio, and acid value. The statistical analysis indicated that the proposed equations predictions agree well with the experimental data. The predicted model shows an (R2) between 0.99-0.98, indicating good fitting between the experimental data and proposed model. The distillate of upgraded palm biodiesel was miscible with the kerosene jet A-1 in all volume fractions under study 5-20%. The economic analysis shows that the production cost per unit of the produced bio jet fuel was much higher than the selling price of the petroleum jet fuel. This price difference is due to the raw materials cost; as the palm oil used is nearly three times that of crude oil. The economic evaluation study reveals that the operating cost of prepared bio jet equals to 2360 $/ton, which is a promising result.

Optimization of multi-pathway production chains and multi-criteria decision-making through sustainability evaluation: a biojet fuel production case study.

Selection of optimal technologies for novel biobased products and processes is a major challenge in process design, especially when are considered many alternatives available to transform materials into valuable products. Furthermore, such technological alternatives vary in their technical performances and cause different levels of economic and environmental impacts throughout their life cycles. Additionally, selection of optimal production pathways requires a shift from the traditional materials management practices to more sustainable practices. This contribution provides a method for optimizing multi-product network systems from a sustainability perspective by applying the GREENSCOPE framework as a sustainable objective function. A case study is presented in which the four GREENSCOPE target areas (i.e., efficiency, energy, economics, and environment) are evaluated by 21 preselected indicators as part of a multi-objective optimization problem of a biojet fuel production network. The biojet fuel production network evaluated in this study consists of four main elements: (1) feedstocks management, (2) conversion technologies, (3) co-products upgrading, and (4) auxiliary sections for in situ production of raw materials and utilities. For the sustainability objective function, the 21 indicators are analyzed considering multiple perspectives of stakeholders to study their influence on the decision-making process. It is, different sets of weighting factors are assigned to each of the four target areas. Hence, this sustainability evaluation from different stakeholders' perspectives allows identifying optimal networks, specific target areas with great potential for improvements, and processing steps with great influence in the entire network performance. As a result, diverse optimal network arrangements were obtained according to the multiple stakeholders' perspectives. This evidences that a win-win situation for all sustainability aspects considered can hardly be reached. Finally, this contribution demonstrated the applicability of the proposed methodology for sustainability evaluation, optimization, and decision-making in the context of a multi-product material facility by developing a multi-objective optimization model.