Biofuels Bioproducts & Biorefining-Biofpr最新文献

Olive tree pruning (OTP) is one of the most abundant sources of biomass waste in the Mediterranean basin. This is especially relevant in southern Spain where olive oil production represents a large part of the economy. Olive tree prunings are mostly either burned or are spread in olive orchards as an organic amendment, or used for heat generation on a domestic scale. However, the lignocellulosic composition of OTP makes it a potential source of biopolymers, thus providing an excellent economic alternative for the olive oil sector. In this work, pretreated OTP fibers were subjected to an optimized alkaline treatment followed by a single-step bleaching reaction with H₂O₂. Afterwards, the cellulose pulp was transformed chemically to obtain cellulose acetate. Noncellulosic components were removed effectively from OTP, thus obtaining a pulp highly purified in cellulose with 71% crystallinity and 355 °C maximum degradation temperature. Nevertheless, a very large amount of cellulose (ca. 50%) was eliminated throughout the process, especially during acid pretreatment, which was responsible for 38% solubilization. A similar level of acetylation and degree of substitution was obtained by using acetylation times in the range of 1 to 6 h. No large differences were observed in the infrared spectra and X-ray diffractograms of the synthesized acetates. However, their thermal stability varied significantly with reaction time, evolving from a multistep degradation pattern to a single and sharp peak between 300 and 400 °C with increasing time. Thermogravimetric curves revealed that at least 5 h (preferably 6 h) were needed to obtain cellulose acetate from OTP with adequate thermal stability for further processing.

In recent years there has been a growing interest in the scale-up and commercialization of lignocellulosic biorefinery. Process simulation is a crucial preliminary study, conducted at the system level, to evaluate the feasibility of industrializing biorefinery operations. Numerous research studies have been conducted on the application of process simulation in lignocellulosic biorefinery, making it essential to provide a detailed introduction to this topic. This paper summarizes two aspects of the application of process simulation in lignocellulosic biorefinery: the production of bioenergy and the production of biochemicals. The bioenergy section describes the application of process simulation to hydrochar, syngas, and bioethanol. The biochemicals section relates to the production processes for cellulose, lignin, and hemicellulose. Additionally, the research status of process simulation in biorefinery are detailed from the following aspects: physical property parameters, kinetic study, the variety of raw materials and validation. Finally, this paper discusses some advances in biorefinery process simulation. It is hoped that this paper will assist the industrialization of lignocellulosic biorefinery.

In this work, the pyrolysis of barley straw (BS) and brown algae (BA) mixed with NaOH as a catalyst was compared. Four different catalyst-to-biomass mass ratios (i.e., 6:100, 8:100, 10:100, and 12:100) and five pyrolysis heating rates were examined. The kinetic parameters (e.g., the activation energy and pre-exponential factor) were evaluated using the Friedman method and kinetic models. For noncatalytic pyrolysis, the average activation energies for BS and BA samples were 139.71 and 183.19 kJ mol⁻¹, respectively. However, the addition of catalyst generally increased the average activation energy of BS samples but decreased that of BA samples. The enthalpy change and Gibbs free energy change revealed that both catalytic and noncatalytic pyrolysis processes were nonspontaneous and endothermic, and the inclusion of catalyst increased the average entropy change of the BS samples but decreased that of the BA samples. Char and biochar yields after pyrolysis were also analyzed quantitatively. These observations provide insight into the differences in catalytic pyrolysis between lignocellulosic and algal biomass species.

Peroxidase is an industrially important enzyme with a broad range of applications. In this study, the extraction, isolation, and purification of peroxidase was conducted with wheat bran as a feedstock. Several commercially available buffers (K₂HPO₄, Na₃PO₄, CH₃COONa, and Tris-base) were explored for the extraction of peroxidase from wheat bran. Of the tested media, sodium acetate buffer gave an excellent performance and displayed maximum protein (0.44 mg mL⁻¹) and enzyme activity (28 U mL⁻¹). A process optimization study was also conducted to obtain the maximum protein concentration and enzyme activity. The intensified process provided 1.39 mg mL⁻¹ protein concentration with 90 U mL⁻¹ enzyme activity with specific enzyme activity of 135.8 U mg⁻¹. Crude enzyme was purified using a three-step process: (a) precipitation, (b) ultrafiltration, and (c) chromatographic purification. Commercially available strong and weak ion exchange resins, with different surface properties, were tested for purification. The weak anion exchange resin showed an excellent performance for maximum binding of peroxidase. Adsorption study investigated the best fit model of Freundlich isotherm with maximum binding capacity of 54 mg mL⁻¹. Overall, purification provided peroxidase with a protein concentration of 1.24 mg mL⁻¹ and 727.58 U mg ⁻¹ specific enzyme activity with purity increased by around ~6.6 fold. The reported process provides a simple and efficient method for the extraction and purification of peroxidase enzyme from wheat bran for its efficient valorization.

The transition to a low-carbon economy endangered the revenues of many oil-dependent regions. This is the case in Rio de Janeiro state, Brazil, which has become highly dependent on oil and gas royalties since the 1970s. At the same time, the circular blue bioeconomy has emerged as a pathway for environmentally sound socioeconomic development. In such a context, a biological resource in many oil-dependent regions is fish processing residue, from which high added-value compounds can be obtained, such as collagen, hydroxyapatite, gelatin, lipids, enzymes, hydrolysates, and bioactive peptides. The present study aims to understand the potential for a future fish waste hydroxyapatite (FHAp) market in the state of Rio de Janeiro (SRJ). The methodological approach integrates technology roadmapping with market and innovation ecosystem assessment. We found that the main techniques for obtaining FHAp were chemical hydrolysis and calcination, and the most innovative and value-added applications were biomaterial for tissue regeneration (BTR) and physical sunblock (PS). The mapping of SRJ companies showed that the state has qualified players in cosmetic and biomedical industries that could develop innovations in BTR and PS made of FHAp. However, the mapping also showed a gap in the FHAp extraction stage, which is essential for the value chain. To find and encourage players to compound this innovation ecosystem, the public power can therefore act as an articulator, providing financial incentives and creating infrastructural conditions, such as a waste pretreatment plant next to the state fishing pole.

The macroalgae residue from the industrial agar extraction process contains a significant amount of carbon and has potential as a renewable feedstock. Unfortunately, it is often overlooked and is poorly utilized. This study aims to valorize this macroalgae residue through pyrolysis to produce silica-rich biochar and other value-added products in the form of biocrude oil (BCO) and biopyrolysis gas. The macroalgae residue was pyrolyzed at 300–700 °C with a heating rate of 20–40 °C/min. Yields of biochar, BCO, and gas of 62%, 25%, and 13% were obtained at a temperature of 700 °C and a heating rate of 20 °C/min. Biochar has a porous structure, a surface area exceeding 15 m²/g, and is dominated by amorphous silica of up to 13%. This silica-rich biochar also contains Na and K, which hold potential benefits in agriculture, serving as soil ameliorants and playing a crucial role in enhancing soil fertility and promoting plant growth. In the meantime, BCO contains 29.3% carboxylic acid group as the most important chemical component. Other than that, the biopyrolysis gas contains mainly CH₄ and H₂ (up to 24–32%), which can act as chemical building blocks. Finally, a simple business scenario of silica-rich biochar production reveals that it has a specific cost of 0.37 US$/kg. It could be economically viable as a soil ameliorant or fertilizer. However, challenges persist in scaling up production to an industrial scale.

In transitioning to a carbon-neutral chemical industry, the intake of fossil feedstocks will have to be reduced by maximizing end-of-life product recycling and introducing alternative feedstocks based on renewable carbon. This perspective article analyses the potential of domestically grown and sourced woody biomass for the supply of renewable carbon for chemicals in Europe. The European chemical industry can become a major consumer of woody biomass in a context where burning wood for energy production is viewed as an unsustainable practice.

The Finnish government has set a target of reaching carbon neutrality by 2035 and renewable energy is playing an increasingly important role in the Finnish energy sector. Bioenergy from forest biomass is currently the most utilized renewable energy resource. European Union regulations are imposing limitations on the use of forest biomass for environmental reasons, however, and the energy sector is having to look for alternative renewable energy options to reach carbon neutrality. This paper reviews the latest changes in the energy industry in Finland and evaluates prospective renewable energy development and fossil fuel replacement in the future Finnish energy system. The study shows that only a combination of all available renewable energy forms can enable the carbon neutrality target to be achieved by 2035. There is a good possibility that Finland can replace fossil fuels fully in the energy sector; wind energy will increase its share of electricity production, and biomass will continue to play a crucial role in the heating sector. Industry and the transport sector, however, face greater challenges and should be studied in more detail.

Biochar is emerging as a potential solution for biomass conversion to meet the ever increasing demand for sustainable energy. Efficient management systems are needed in order to exploit fully the potential of biochar. Modern machine learning (ML) techniques, and in particular ensemble approaches and explainable AI methods, are valuable for forecasting the properties and efficiency of biochar properly. Machine-learning-based forecasts, optimization, and feature selection are critical for improving biomass management techniques. In this research, we explore the influences of these techniques on the accurate forecasting of biochar yield and properties for a range of biomass sources. We emphasize the importance of the interpretability of a model, as this improves human comprehension and trust in ML predictions. Sensitivity analysis is shown to be an effective technique for finding crucial biomass characteristics that influence the synthesis of biochar. Precision prognostics have far-reaching ramifications, influencing industries such as biomass logistics, conversion technologies, and the successful use of biomass as renewable energy. These advances can make a substantial contribution to a greener future and can encourage the development of a circular biobased economy. This work emphasizes the importance of using sophisticated data-driven methodologies such as ML in biochar synthesis, to usher in ecologically friendly energy solutions. These breakthroughs hold the key to a more sustainable and environmentally friendly future.

This study presents a multidisciplinary approach for dealing with the environmental problems related to agro-industrial coffee residues. The exploitation of these residues allows biomolecules to be obtained from renewable sources and enables the preparation of CO₂-neutral biocomposites, with the advantages of reducing fossil depletion, avoiding climate-altering emissions, and limiting plastic pollution. Coffee silverskin (CSS), a by-product deriving from coffee bean roasting, was subjected to different eco-friendly extraction processes, such as ultrasound-assisted, CO₂-supercritical, and water-subcritical extractions to recover caffeine, phytosterols, and polyphenols. The residues remaining after the extractions were further valorized as fillers into biocomposites based on poly(1,4-butylene succinate) (PBS). Biocomposites (filler content up to 30 wt%) were prepared by melt mixing, and they were characterized in terms of their thermal, mechanical, and morphological performance. The effect of the presence of residues derived from different extraction procedures on the resulting properties of biocomposites was assessed and discussed, and the ultrasound-assisted treatment was found to leave the CSS residue as the most compatible with the PBS matrix. The results of this study indicate that the proposed bio-refinery could successfully and fully valorize the CSS agro-industrial residues, even in its ultimate step, producing biocomposites characterized by low economic and environmental impact; these new materials will be a possible bio-alternative to the traditional polymers commonly used by the packaging industry.