Simultaneous Production Research Articles

Techno-economic ionic liquid-based capturing, electrochemical reduction, and hydrogenation of carbon dioxide in the simultaneous production of formic acid and biomethane

CO2 utilization is vital for mitigating climate change by converting CO2 into valuable products, promoting environmental protection and resource efficiency. Novel pathways for CO2 utilization to produce formic acid are proposed namely solute phase electroreduction, gas phase electroreduction, and hydrogenation, are investigated. Employing multi-objective optimization with a deep neural network surrogate model, this study identifies optimal process conditions balancing capital and operational expenditures. The result shows that CO2 hydrogenation ($868 ton−1) exhibits the lowest production cost followed by gas-phase electroreduction ($986 ton−1) and solute-phase electroreduction ($2103 ton−1). The result also shows that without any intervention at all only hydrogenation can generate profit. Furthermore, an in-depth analysis of CO2 emissions indicates that gas phase electroreduction results in the lowest CO2 emissions (0.7 kg CO2 kgHCOOH−1) among the examined pathways. Insights from our research suggest a minimum current density of 417.3 mA cm−2 is recommended to achieve at least parity with hydrogenation in terms of production cost. To push the commercialization of gas-phase electroreduction, besides current density improvement, electricity cost reduction, and carbon trading mechanism is proposed to reduce the production cost.

Investigating the efficiency of a two-stage anaerobic-aerobic process for the treatment of confectionery industry wastewaters with simultaneous production of biohydrogen and polyhydroxyalkanoates.

The scope of the current study was to investigate the efficiency of a two-stage anaerobic-aerobic process for the simultaneous treatment and valorization of selective wastewater streams from a confectionary industry. The specific wastewater (confectionary industry wastewater, CIW) was a mixture of the rinsing eluting during washing of the cauldrons in which jellies and syrups were produced, and contained mainly readily fermentable sugars, being thus of high organic load. The first stage of the process was the dark fermentation (DF) of the CIW in continuous, attached-biomass systems, in which the effect on hydrogen yields and distribution of metabolites were studied for different packing materials (ceramic or plastic), hydraulic retention times, HRTs (12 h–30 h) and feed substrate concentration (20 g COD/L- 50 g COD/L). In the second stage, the effectiveness of the aerobic treatment of the DF effluents was evaluated in terms of the reduction of the organic load and the production of polyhydroxyalkanoates (PHAs) through an enriched mixed microbial culture (MMC). The MMC was developed in a continuous draw and fill system, in which the accumulation potential of PHAs was studied. It was shown that the hydrogen production rates decreased for increasing substrate concentration and HRTs, with a maximum of 12.70 ± 0.35 m3 H2/m3 initial CIW achieved for the lowest HRT and feed concentration and using ceramic beads as packing material. Butyrate, acetate and lactate were the main metabolites generated in all cases, in different ratios. The distribution of metabolites during DF was shown to highly affect the efficiency of the second process in terms of both the reduction of organic load and the PHAs yields. The highest removal of organic load achieved after 48 h of aerobic treatment was 84.0 ± 0.9 %, whereas the maximum PHAs yield was 21.46 ± 0.13 kg PHAs/m3 initial CIW.

Driving tetracycline hydrochloride degradation and concomitant hydrogen peroxide photosynthesis in a neutral environment over sulphur and oxygen codoped carbon nitride

The investigation of an artificial photosynthesis system for contaminant treatment and consecutive hydrogen peroxide formation is imperative but challenging, whereas the conversion efficiency is relatively low and far away from the demand for social development. Herein, oxygen and sulphur were collectively introduced into carbon nitride nanosheets (OSCN), together with sufficient edge and basal plane active sites. The as-synthesized sample could achieve a degradation efficiency of 84% for 100 mg/L tetracycline hydrochloride, together with simultaneous hydrogen peroxide production of 366 μmol g−1 h−1 under environmentally friendly neutral conditions. Intriguingly, the addition of tetracycline hydrochloride can accelerate hydrogen peroxide generation, which thus in turn speed up tetracycline hydrochloride degradation. It was revealed that the optimized electronic structure, promoted light-harvesting, and enhanced charge carriers separation capacity are conducive for the synchronous oxygen reduction and contaminant oxidation procedure in large measure. Furthermore, the degradation and hydrogen peroxide generation can be maintained even after 15 cycles, demonstrating the stability of OSCN and its possibility for practical applications. The degradation pathway and in-deep reaction mechanism are carried out accordingly. Additionally, such a synchronously promoted reaction can be extended to some other pollutants, like phenol and 2,4-dichlorophenol. This interesting work provides a novel strategy for pollutants removal and concurrent hydrogen peroxide generation.

Designing and fabricating a neoteric immobilized Z-scheme V2O5/FeVO4/430-stainless steel foil photocatalyst composite film for tetracycline degradation with synchronous hydrogen production

For traditional photocatalyst composite films, the produced hydrogen and carbon dioxide are mixed together, which is not conducive to the direct use of hydrogen. In this study, a novel immobilized Z-scheme V2O5/FeVO4/430-stainless steel foil (V2O5/FeVO4/430-SSF) photocatalyst composite film was constructed. Thereby, the hydrogen and the carbon dioxide can separately generated on both sides of the photocatalytst film and the pure hydrogen can be obtained. The results show that the photocatalyst composite film prepared under optimal conditions has excellent photocatalytic activity in organic pollutant degradation with simultaneous hydrogen production. Under simulated sunlight irradiation for 120 min, the degradation ratio of tetracycline is 77.53% and the hydrogen production amount reaches 370.81 µmol/dm2. It is hoped that this work could provide some guiding suggestions to designing a photocatalyst composite film for efficient photocatalytic degradation of organic pollutants with simultaneous production of pure hydrogen in the future.

Photoelectrocatalytic activation of sulfate for sulfamethoxazole degradation and simultaneous H2 production by bifunctional N,P co-doped black-blue TiO2 nanotube array electrode

In recent years, sulfate radical (SO4•−)-based advanced oxidation processes and hybrid water electrolysis for hydrogen production have attracted widespread attention. However, the conventional electrochemical persulfate activation requires mass/expensive persulfate reagent, limiting its practical application due to high operation cost. In this work, using bifunctional N, P co-doped black-blue TiO2 nanotube arrays (N,P-BTNAs) as a wide-spectrum absorptive photoanode, we report the synergistic PEC sulfate activation for effective degrading sulfamethoxazole (SMX) antibiotic and simultaneous generating H2 at N,P-BTNAs cathode. With sulfate as h+ scavenger and SO4•− precursor, HO•, SO4•−, 1O2 and h+ are generated during PEC activation process. Detailed physicochemical characterization and density functional theory (DFT) calculations revealed that the Ti3+, P5+, N triple-doping induced a narrowed band gap (2.78 eV), a rapid separation/transfer of photo-induced carriers, an accelerated h+ extraction/utilization, and an optimized H binding/releasing ability, resulting in an outstanding PEC sulfate activation for SMX degradation (0.05368 min−1) and H2 evolution efficiency (132.3 μmol/cm2/h) under optimal conditions. This study provides a novel strategy for efficient contaminants removal and stable H2 production simultaneously, via the synergistic PEC activation of the coexisted sulfate using the bifunctional N,P-BTNAs electrode.

Bifunctional nickel phosphide nanoparticle/nickel cobalt sulfide nanosheet framework for electrocatalytic simultaneous hydrogen evolution and 2,5-Furandicaroxylic acid production

Replacing the O2 evolution reaction of water splitting with a thermodynamically more favorable reaction has attracted considerable attention for simultaneous value-added feedstock formation coupled with H2 production. Herein, bifunctional nickel phosphide nanoparticle/nickel cobalt sulfide nanosheet framework (NCSP150) is constructed on Ni foam for electrocatalytic hydrogen evolution reaction (HER) and 5-hydroxymethyl furfural (HMF) oxidation reaction (HMFOR) to 2,5-furandicaroxylic acid (FDCA) in 0.1 M KOH where HMF degradation is negligible. NCSP150 respectively demonstrates a Faradaic efficiency of 98.5 % for H2 generation at 10 mA cm−2 in 0.1 M KOH aqueous solution and exhibits a Faradaic efficiency of 95.2 % for FDCA formation at 1.52 V vs. RHE in a 10 mM HMF/0.1 M KOH aqueous solution. Moreover, NCSP150 sustains superior electrocatalytic performances for at least 12 h in the 0.1 M KOH electrolyte. In a two-electrode H cell using NCSP150 as both cathode and anode, the cell voltage required to afford the current density of 10 mA cm−2 is less 153 mV than water electrolysis when adding 5 mM HMF in 0.1 M KOH. This work emphasizes bifunctional NCSP150 as a promising non-precious-metal electrocatalyst for simultaneous hydrogen evolution and FDCA production in 0.1 M KOH, suitable for scaling up industrial production.

Revisiting the role of ascorbate oxidase in plant systems.

Ascorbic acid (AsA) plays an indispensable role in plants, serving as both an antioxidant and a master regulator of the cellular redox balance. Ascorbate oxidase (AO) is a blue copper oxidase that is responsible for the oxidation of AsA with the concomitant production of water. For many decades, AO was erroneously postulated as an enzyme without any obvious advantage, as it decreases the AsA pool size and thus is expected to weaken plant stress resistance. It was only a decade ago that this perspective shifted towards the fundamental role of AO in orchestrating both AsA and oxygen levels by influencing the overall redox balance in the extracellular matrix. Consistent with its localization in the apoplast, AO is involved in cell expansion, division, resource allocation, and overall plant yield. An increasing number of transgenic studies has demonstrated that AO can also facilitate communication between the surrounding environment and the cell, as its gene expression is highly responsive to factors such as hormonal signaling, oxidative stress, and mechanical injury. This review aims to describe the multiple functions of AO in plant growth, development, and stress resilience, and explore any additional roles the enzyme might have in fruits during the course of ripening.

Applications of Geothermal Energy for Desalination: A Review Technological Advancement and Water Security

Geothermal energy, harnessed through the Earth's thermal resources, emerges as an enduring and sustainable remedy to tackle the urgent concern of water scarcity through desalination. By harnessing the innate thermal reservoirs within the planet, geothermal energy provides a distinctive avenue for generating heat and electricity, particularly when synergistically aligned with desalination procedures. To understand the insights of the implications of geothermal energy for desalination, we conducted a comprehensive literature review analysis. Main objectives of the review are to (i.) disseminate insights into geothermal-driven desalination, (ii.) explore potentialities and obstacles of geothermal-driven desalination, and (iii.) evaluate forthcoming environmental, socio-economic predicaments associated with this approach. We selected 50 peer reviewed scholarly communications published using Google Scholar from 2000 to 2022, focusing on impactful English-language publications within esteemed scientific journals. We found multi-effect evaporation/distillation (MED); multi-stage flash distillation (MSF); thermal vapor compression (TVC) and mechanical vapor compression (MVC). Membrane processes include electrodialysis (ED), reverse osmosis (RO), and membrane desalination are the common techniques used across mainly in Australia, USA, UAE, Sub-Saharan and African nations, and Japan. The integration of innovative designs of these methods can enhance the efficacy and cost-efficiency of geothermal desalination systems. Furthermore, critical environmental, social, and economic concerns linked to geothermal-driven desalination were identified. We noted that high-capacity factor for stable heat supply, independent of seasonal changes, ideal temperatures (70-90° C) for low-temperature desalination, cost-effectiveness with simultaneous power and water production, environmentally friendly with no emissions, versatile to meet energy demand across scales are some of main advantages of selection of geothermal energy for desalination. Some studies showed that geothermal energy for desalination is practical and effective, especially in areas facing water scarcity, strengthening water security. However, challenges persist, necessitating inventive solutions encompassing the pursuit of robust materials designed for high-temperature operation and streamlining energy conversion and integration processes. Other foreseen difficulties include the potential environmental impacts on geothermal reservoirs and the necessity for careful resource management to maintain a fair socio-economic equilibrium. Thus, the future research direction should be mainly focus on harnessing geothermal heat to drive the process, significantly reducing energy consumption and mitigating carbon emissions to potentially be employed across the world.
 
 Keywords: Carbon emission mitigation, Desalination, Energy conservation, Geothermal Energy, Water security

Renewable gases production coupled to synthetic wastewater treatment through a microbial electrolysis cell

This study describes the use of a microbial electrolysis cells for the production of gaseous biofuels sustained by the oxidation of a synthetic wastewater. During the overall experimental investigation, the MEC’s bioanode removed on average 855 ± 57 mgCOD/d producing an average electric current of 66 ± 7 mA which was diverted into gaseous biofuels like biomethane, biohydrogen and biohythane. Three different MEC cathodic configurations were investigated selecting the electrodic materials (graphite granules GG, and mixed metal oxide MMO) and operating conditions (pH of the catholyte, additional sorption chamber). Biomethane production increased from 26 ± 4–102 ± 8 meq/d when the MMO electrode was used with respect to GG electrodic material. In contrast, the MMO electrode in combination with a CO2 sorption chamber was successfully utilized for simultaneous H2 production and CO2 sorption from a N2/CO2 mixture which simulates an anaerobic digestion biogas. The combination of H2 production and CO2 sorption allowed to obtain a gaseous mixture composed of 9% H2, 5% CO2, and 80% N2 that according to the assumption of replacing the N2/CO2 mixture with real biogas corresponded to a commercial-grade biohythane. Overall, the results highlight the potential of MECs as an efficient approach for biogas upgrading, allowing biohythane production increasing CH4 content and lowering CO2 concentration.

Membrane performance of pressure-retarded osmosis using simulated hydroxide-based CO2-captured draw solutions

This study proposes a novel hybrid process that integrates direct air capture (DAC) and pressure-retarded osmosis (PRO) to address high water and energy demands of the DAC process and achieve simultaneous decarbonization and energy production. To explore the PRO performance in this hybrid process, membrane fouling behaviors were investigated by employing forward osmosis membranes in the PRO mode with various Na- and K-based draw solutions that simulated hydroxide-based CO2-captured solutions. Especially calcium (Ca2+) and alginate were dosed into the draw solutions as representatives of scaling precursor and organic foulants during long-term DAC-PRO operation respectively. The results revealed that (1) the presence of calcium in the NaHCO3 and KHCO3 draw solutions formed CaCO3 precipitates, whose amounts, morphologies, and particle size were associated with the dosed Ca2+ concentration and alkali solution type. (2) Higher calcium amounts in the NaHCO3 and KHCO3 draw solutions promoted more deposition of rhombohedral CaCO3 crystals on the membrane, leading to a lower water flux (Jw) and higher reverse salt flux (Js) due to increased hydraulic resistance and cake-layer-enhanced concentration polarization. (3) Dosing calcium (40 mM) into a mixture of HCO3- and CO32- draw solution resulted in accumulation of irregular-shape CaCO3 crystals on the membrane and an increase of Jw, possibly relating to the increased membrane hydrophilicity due to decreased solubility of the solute at a higher pH level. (4) The addition of alginate into calcium-dosed (40 mM) draw solutions did not influence Jw and Js but increased deposited foulants. This suggests that deposited alginate may loosely attach to CaCO3 crystals, instead of creating a dense fouling layer by bridging with Ca2+.

Cyan Hydrogen Process: A New Route for Simultaneous Hydrogen Production and Carbon Valorization.

Hydrogen is expected to largely contribute to the near-future circular economy. Today, most hydrogen is still produced from fossil fuels or renewable pathways with low efficiency and high cost. Herein, a proof of concept for a novel hydrogen production process is proposed, here named cyan hydrogen, inspired by a combination of the green and blue processes, due to the key role played by water and the low carbon content in the gas phase, respectively. The developed novel process, recently patented and demonstrated at the lab scale, is based on successive steps in which ethanol (5.0 mL) and water (10.0 mL) are alternately fed, with a fixed initial amount of sodium metaborate (2.0 g), in a batch reactor at 300 °C. Preliminary results showed the simultaneous production of a 95% v/v hydrogen stream, a polymeric byproduct with a repetitive carbon pattern -CH2-CH2-, and a liquid phase rich in oxygenated chemicals at temperatures lower than conventional hydrogen production processes.

Two at once: simultaneous increased production of astaxanthin and mycosporines in a single batch culture using a Phaffia rhodozyma mutant strain.

Phaffia rhodozyma is a basidiomycetous yeast characterized by its production of the carotenoid pigment astaxanthin, which holds high commercial value for its significance in aquaculture, cosmetics and as nutraceutics, and the UV-B-absorbing compound mycosporine-glutaminol-glucoside (MGG), which is of great biotechnological relevance for its incorporation into natural sunscreens. However, the industrial exploitation has been limited to the production of astaxanthin in small quantities. On the other hand, the accumulation of MGG in P. rhodozyma was recently reported and could add value to the simultaneous production of both metabolites. In this work, we obtain a mutant strain that overproduces both compounds, furthermore we determined how the accumulation of each is affected by the carbon-to-nitrogen ratio and six biotic and abiotic factors. The mutant obtained produces 159% more astaxanthin (470.1μgg-1) and 220% more MGG (57.9mgg-1) than the parental strain (295.8μgg-1 and 26.2mgg-1 respectively). Furthermore, we establish that the carotenoids accumulate during the exponential growth phase while MGG accumulates during the stationary phase. The carbon-to-nitrogen ratio affects each metabolite differently, high ratios favoring carotenoid accumulation while low ratios favoring MGG accumulation. Finally, the accumulation of both metabolites is stimulated only by photosynthetically active radiation and low concentrations of hydrogen peroxide. The mutant strain obtained is the first hyper-productive mutant capable of accumulating high concentrations of MGG and astaxanthin described to date. The characterization of how both compounds accumulate during growth and the factors that stimulate their accumulation, are the first steps toward the future commercial exploitation of strains for the simultaneous production of two biotechnologically important metabolites.

Prospects for combined analyses of hadronic emission from γ\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\gamma $$\\end{document}-ray sources in the Milky Way with CTA and KM3NeT

The Cherenkov Telescope Array and the KM3NeT neutrino telescopes are major upcoming facilities in the fields of γ\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\gamma $$\\end{document}-ray and neutrino astronomy, respectively. Possible simultaneous production of γ\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\gamma $$\\end{document} rays and neutrinos in astrophysical accelerators of cosmic-ray nuclei motivates a combination of their data. We assess the potential of a combined analysis of CTA and KM3NeT data to determine the contribution of hadronic emission processes in known Galactic γ\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\gamma $$\\end{document}-ray emitters, comparing this result to the cases of two separate analyses. In doing so, we demonstrate the capability of Gammapy, an open-source software package for the analysis of γ\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\gamma $$\\end{document}-ray data, to also process data from neutrino telescopes. For a selection of prototypical γ\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\gamma $$\\end{document}-ray sources within our Galaxy, we obtain models for primary proton and electron spectra in the hadronic and leptonic emission scenario, respectively, by fitting published γ\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\gamma $$\\end{document}-ray spectra. Using these models and instrument response functions for both detectors, we employ the Gammapy package to generate pseudo data sets, where we assume 200 h of CTA observations and 10 years of KM3NeT detector operation. We then apply a three-dimensional binned likelihood analysis to these data sets, separately for each instrument and jointly for both. We find that the largest benefit of the combined analysis lies in the possibility of a consistent modelling of the γ\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\gamma $$\\end{document}-ray and neutrino emission. Assuming a purely leptonic scenario as input, we obtain, for the most favourable source, an average expected 68% credible interval that constrains the contribution of hadronic processes to the observed γ\\documentclass[12pt]{minimal} \\usepackage{amsmath} \\usepackage{wasysym} \\usepackage{amsfonts} \\usepackage{amssymb} \\usepackage{amsbsy} \\usepackage{mathrsfs} \\usepackage{upgreek} \\setlength{\\oddsidemargin}{-69pt} \\begin{document}$$\\gamma $$\\end{document}-ray emission to below 15%.

Control of odorants in swine manure and food waste co-composting via zero-valent iron /H2O2 System

Odors have posed challenges to the advancement of aerobic composting. This work aims to identify the primary components responsible for odors and assess the effectiveness and mechanisms of the zero-valent iron/H2O2 system controlling various odorants in aerobic composting. Swine manure and food waste were used as composting materials, with the addition of zero-valent iron and hydrogen peroxide to mitigate odor emissions. Results revealed that odorants included ammonia, hydrogen sulfide, and 22 types of volatile organic compounds (VOCs), with ethyl acetate, heptane, and dimethyl disulfide being predominant. Among the odorants emitted, ammonia accounted for 75.43%, hydrogen sulfide for 0.09%, and identified VOCs for 24.48%. The ZVI/H2O2 system showed a significant reduction in ammonia and VOCs emission, with the reduction of 51% (ammonia) and 41.3% (VOCs) respectively, primarily observed during the thermophilic period. The occurrence of Fenton-like reactions and changes in key microbial populations were the main mechanisms accounting for odor control. The occurrence of Fenton-like reaction was confirmed by X-ray photoelectron spectroscopy and reactive oxygen detection, showing the oxidation of zero-valent iron by H2O2 to higher valence elemental iron, and the simultaneous production of ·OH. Microbial analysis indicated that an enrichment of specific microorganisms with Bacillus contributed to feammonx and Bacillaceae contributed to organic biodegradation. Redundancy analysis highlighted the role of key microbial species (Bacillaceae, Bacillus, and Ureibacillus) in effectively reducing the level of ammonia and volatile organic compounds. These novelty findings illustrated that the potential of this system is promising for controlling the emission of odorants and aerobic composting reinforcement.

A fuel gas waste heat recovery-based multigeneration plant integrated with a LNG cold energy process, a water desalination unit, and a CO2 separation process

Development of the multigeneration plants based on the simultaneous production of water and energy can solve many of the current problems of these two major fields. In addition, the integration of fossil power plants with waste heat recovery processes in order to prevent the release of pollutants in the environment can simultaneously cover the environmental and thermodynamic improvements. Besides, the addition of a carbon dioxide (CO2) capturing cycles with such plants is a key issue towards a sustainable environment. Accordingly, a novel waste heat recovery-based multigeneration plant integrated with a carbon dioxide separation/liquefaction cycle is proposed and investigated under multi-variable assessments (energy/exergy, financial, and environmental). The offered multigeneration system is able to generate various beneficial outputs (electricity, liquefied CO2 (L-CO2), natural gas (NG), and freshwater). In the offered system, the liquified natural gas (LNG) cold energy is used to carry out condensation processes, which is a relatively new idea. Based on the results, the outputs rates of net power, NG, L-CO2, and water were determined to be approximately 42.72 MW and 18.01E+03, 612 and 3.56E+03 kmol/h, respectively. Moreover, the multigeneration plant was efficient about 32.08% and 87.72%, respectively, in terms of energy and exergy. Economic estimates indicated that the unit product costs of electricity and liquefied carbon dioxide production, respectively, were around 0.0466 USD per kWh and 0.0728 USD per kg-CO2. Finally, the total released CO2 was about 0.034 kg per kWh. According to a comprehensive comparison, the offered multigeneration plant can provide superior environmental, thermodynamic, and economic performances compared to similar plants. Moreover, there was no need to purchase electricity from the grid.

Advances in the co-production of biosurfactant and other biomolecules: statistical approaches for process optimization.

An efficient microbial conversion for simultaneous synthesis of multiple high-value compounds, such as biosurfactants and enzymes, is one of the most promising aspects for an economical bioprocess leading to a marked reduction in production cost. Although biosurfactant and enzyme production separately have been much explored, there are limited reports on the predictions and optimization studies on simultaneous production of biosurfactants and other industrially important enzymes, including lipase, protease, and amylase. Enzymes are suited for an integrated production process with biosurfactants as multiple common industrial processes and applications are catalysed by these molecules. However, the complexity in microbial metabolism complicates the production process. This study details the work done on biosurfactant and enzyme co-production and explores the application and scope of various statistical tools and methodologies in this area of research. The use of advanced computational tools is yet to be explored for the optimization of downstream strategies in the co-production process. Given the complexity of the co-production process and with various new methodologies based on artificial intelligence (AI) being invented, the scope of AI in shaping the biosurfactant-enzyme co-production process is immense and would lead to not only efficient and rapid optimization, but economical extraction of multiple biomolecules as well.

Application of Trametes pubescens for dye removal and biological pretreatment of sugarcane bagasse

AbstractSugarcane bagasse (SB) is an abundantly available agrowaste that is used extensively as a substrate for the production of different industrial enzymes. It is a renewable resource, rich in fermentable sugars. However, the presence of lignin makes it difficult for microbes to degrade it and so it is difficult to utilize it. Keeping in mind the role of white rot fungi in lignin degradation, Trametes pubescens MB89 was used in this study for the delignification of SB with the simultaneous production of laccase. The fungus was also used for the degradation of malachite green dye. A Box–Behnken design (BBD) was used to optimize variables affecting solid state fermentation of SB for laccase production. The leftover SB after fermentation was used for cellulase production by the thermophilic bacterium Neobacillus sedimentimangrovi UE25. The BBD depicted optimized conditions as 60% moisture, particle size 100 μ, 10 days’ incubation period, 450 μM CuSO4, and a temperature of 30 °C. The laccase titers of 1271 IU mL−1 were obtained under optimized conditions. Neobacillus sedimentimangrovi UE25 produced 4.574 IU mL−1 of endoglucanase and 1.812 IU mL−1 of β‐glucosidase by utilizing fungal pretreated SB. Scanning electron microscopy and Fourier transform infrared spectroscopy confirmed the impact of fungal cultivation on SB. Pores were observed after microbial pretreatment and there were changes in the morphological characteristics such as the pith and fiber of SB. To test the ability of laccase to break down aromatic dyes, we grew the fungus T. pubescens MB89 in a nutrient‐rich medium supplemented with malachite green dye. The fungus was able to remove 73.68% of the malachite green dye from the medium in 24 h. This shows that T. pubescens MB89 has a range of potential applications for environmental and industrial purposes.

A math-heuristic approach for scheduling the production and delivery of a mobile additive manufacturing hub

This paper investigates an innovative printing-while-delivering paradigm within a mobile additive manufacturing (MAM) hub. Different from the conventional production-first-delivery-second (PFDS) mode, the MAM hub, comprising a 3D printer and a truck, can seamlessly integrate the production and delivery processes. Throughout the delivery process of the MAM hub, the embedded 3D printer within the truck concurrently prints products for customers in batches. This capability significantly diminishes customer dissatisfaction caused by time delays between order placement and product receipt, which requires coordinating the delivery routing of truck and the production scheduling of 3D printer. To tackle this problem, a mixed integer programming model is firstly established to minimize the required time of the MAM hub returning to depot after completing all deliveries. Then, a math-heuristic approach combining the genetic algorithm and branch-and-bound is devised to solve the mathematical model efficiently. The delivery sequence of truck is represented as a chromosome in the genetic algorithm; while, for each delivery sequence, the optimal production scheduling of 3D printer is obtained by branch-and-bound based on the theoretical analysis about the relationship between production and delivery sequences. In the numerical experiments, the proposed math-heuristic algorithm produces results identical to CPLEX solver outcomes in small-scale cases. For larger instances, it outperforms traditional genetic algorithms by 3.39% to 19.54%. The proposed batch printing mode consistently surpasses the non-batch mode by 10% to 25%. Moreover, compared to PFDS, the printing-while-delivering paradigm reduces trip time by over 40%. Finally, we analyze the effects of customer quantity, distribution radius, and printing time on the objective, providing management insights about optimal production and delivery strategy. The research finding not only aids in scheduling the MAM hub but also holds the potential to address other applications characterized by simultaneous production and delivery requirements.

Exploring biorefinery alternatives for biowaste valorization: a techno-economic assessment of enzymatic hydrolysis coupled with anaerobic digestion or solid-state fermentation for high-value bioproducts

ABSTRACT Enzymatic hydrolysis of organic waste is gaining relevance as a complementary technology to conventional biological treatments. Moreover, biorefineries are emerging as a sustainable scenario to integrate waste valorization and high-value bioproducts production. However, their application on municipal solid waste is still limited. This study systematically evaluates the techno-economic feasibility of the conversion of the organic fraction of municipal solid waste (OFMSW) into high-value bioproducts through enzymatic hydrolysis. Two key variables are examined: (a) the source of the enzymes: commercial or on-site produced using OFMSW, and (b) the treatment of the solid hydrolyzate fraction: solid-state fermentation (SSF) for the production of biopesticides or anaerobic digestion for the production of energy. As a result, four different biorefinery scenarios are generated and compared in terms of profitability. Results showed that the most profitable scenario was to produce enzymes on-site and valorize the solid fraction via SSF, with an internal rate of return of 13%. This scenario led to higher profit margins (74%) and a reduced payback time (6 years), in contrast with commercial enzymes that led to an unprofitable biorefinery. Also, the simultaneous production of higher-value bioproducts and energy reduced the economic dependence of OFMSW treatment on policy instruments while remaining energetically self-sufficient. The profitability of the biorefinery scenarios evaluated was heavily dependent on the enzyme price and the efficiency of the anaerobic digestion process, highlighting the importance of cost-efficient enzyme production alternatives and high-quality OFMSW. This paper contributes to understanding the potential role of enzymes in future OFMSW biorefineries and offers economical insights on different configurations.

Uncovering the electrooxidation behavior of 5-hydroxymethylfurfural on Ni/Co electrodes

Biomass, derived from plant photosynthesis that captures carbon dioxide to form carbohydrates, offers vast renewable reserves. The electrooxidation of biomass, coupled with the hydrogen evolution reaction, enables the simultaneous production of biomass-based plastic monomers and green hydrogen, attracting significant scholarly interest. However, ambiguity remains regarding the adsorption mechanism at the catalyst surface (Langmuir-Hinshelwood or Eley-Rideal) and the adsorbed substrate groups. To address this, we prepared a Ni/Co electrode for the electrooxidation of 5-hydroxymethylfurfural (HMF) into 2,5-furandicarboxylic acid (FDCA) through a corrosion reaction and electro-reduction pathway. HMF conversion reached 100.00%, FDCA yield reached 96.82%, and Faradic efficiency (FE) reached 92.14%. Meaningfully, utilizing in-situ spectroscopy and electrochemical methods, this work provided valuable insights into active sites and catalyst surface adsorption.