Properties Of Bio-oil Research Articles

Pyrolysis of sawdust in a horizontal tube furnace: Effects of temperature and heating rate on product composition

The abundant sawdust waste from the timber production industries in Malaysia can be a potential biomass feedstock for pyrolysis process. However, the understanding of product composition and bio-oil quality from sawdust pyrolysis remains limited in Malaysian’s context. In this study, pyrolysis of sawdust was conducted in a horizontal tube furnace to investigate the effects of temperatures (400-550 °C) and heating rates (10-20 °C/min) on the composition of products, quality and properties of bio-oil. According to Gas chromatography (GC) analysis, phenol group appears to be the major compound in the bio-oil. The chemical components of bio-oil were found to be richer at lower reaction temperatures (400-450 °C), where it showcased the presence of phenols, ketones, carboxylic acids, furans, aldehydes, alkenes, alcohols, ether and amine. At increased reaction temperatures (500–550 °C), the process favoured the production of catechol (17%). The yield of bio-char decreased with increasing temperatures and heating rates due to the loss of volatile matter, and 400 °C proved to be the optimum temperature for maximum biochar yield. The biochar also displays porous structure, with increased adsorption capacity. Since the pyrolysis of sawdust could produce phenolic compounds, it appears to be a potential feedstock for biomass pyrolysis.

Creation of Technology and Devices for the Preparation of Motor Fuels Containing Biocomponents

Background: In the world, active research is being conducted to create motor fuels containing bio-oil as a component, derived from renewable, environmentally friendly sources of raw materials such as wood processing waste, agriculture, marine algae, etc. One of the most commonly used technologies for bio-oil production is fast pyrolysis. Due to the physical and chemical properties of such bio-oil, direct blending with petroleum motor fuel is not possible. Objective: The goal of the conducted research was to develop technology and devices to address this issue. Fundamental developments in the field of nonlinear wave mechanics formed the basis for these endeavors. Methods: During the research, designs for motor fuel preparation devices were developed, and mathematical modeling of the mixing processes of fuel components was carried out. The obtained data were analyzed and transferred to natural samples, which were examined during experiments. Results: As a result, blended fuels based on bio-oil (up to 15% by weight) and diesel fuel (marine) with stability of up to 10 days without the use of surface-active substances (SF) and 25-30 days with the addition of SF (up to 0.5% by weight) were obtained. Conclusion: Fuel containing SF is re-homogenized by traditional stirring for at least 3 months. The obtained results confirmed the correctness of the chosen approach and the feasibility of using the developed technology for preparing blended motor fuel containing bio-oil. conclusion: Based on the research results, the developed technology and cavitation wave devices can be recommended for the preparation of mixtures of motor fuels with bio-oil

Physico-Chemical Properties of Bio-Oils as Cutting Fluids: A Comparative Investigation

Physico-Chemical Properties of Bio-Oils as Cutting Fluids: A Comparative Investigation

Improvement of Properties of Bio-Oil from Biomass Pyrolysis in Auger Reactor Coupled to Fluidized Catalytic Bed Reactor

The goal of this research work was to investigate the improvement of bio-oil issued from beechwood biomass through catalytic de-oxygenation. Pyrolysis was conducted in an auger reactor and the catalytic treatment was performed in a fluidized catalytic bed reactor. Lab-synthesized Fe-HZSM-5 catalysts with different iron concentrations were tested. BET specific surface area, BJH pore size distribution, and FT-IR technologies were used to characterize the catalysts. Thermogravimetric analysis was used to measure the amount of coke deposited on the catalysts after use. Gas chromatography coupled to mass spectrometry (GC-MS), flame ionization detection (GC-FID), and thermal conductivity detection (GC-TCD) were used to identify and quantify the liquid and gaseous products. The pyrolysis temperature proved to be the most influential factor on the final products. It was observed that a pyrolysis temperature of 500 °C, vapor residence time of 18 s, and solid residence time of 2 min resulted in a maximum bio-oil yield of 53 wt.%. A high percentage of oxygenated compounds, such as phenolic compounds, guaiacols, and the carboxylic acid group, was present in this bio-oil. Catalytic treatment with the Fe-HZSM-5 catalysts promoted gas production at the expense of the bio-oil yield, however, the composition of the bio-oil was strongly modified. These properties of the treated bio-oil changed as a function of the Fe loading on the catalyst, with 5%Fe-HZSM-5 giving the best performance. A higher iron loading of 5%Fe-HZSM-5 could have a negative impact on the catalyst performance due to increased coke formation.

Combination of integrated machine learning model frameworks and infrared spectroscopy towards fast and interpretable characterization of model pyrolysis oil

Model pyrolysis oil (bio-oil) is a promising bio-fuel with complex and unstable contents, making its fast characterization an essential demand in industrial production. This study proposed an integrated machine learning framework to predict elemental composition, low heating value, and unsaturated concentration from infrared spectra, achieving fast and interpretable characterization of bio-oil. In the integrated framework, a peak loading-based strategy was used to dimensionally reduce the spectral data. Bayesian optimized random forest (RF) and extreme gradient boosting (XGBoost) models were used to predict bio-oil properties from dimensionally reduced spectral data. Ensemble learning was used to combine RF and XGBoost models together for better predicting performance. Results showed that the proposed characterization method achieved an average accuracy of 99.53 %, a low RMSE value of 0.726, and an R2 of 0.98. The Shapley value analysis revealed that the vibration of NH2 stretch (1594 cm−1), C-H stretch (2868 cm−1), and C-N stretch in the aromatic ring (1229 cm−1) have a significant contribution to the characterization results. The working mechanism of the proposed characterization method was interpreted by the internal relationship among spectral peak location/height, functional group species/amount, and the predicted characteristics. The results are hoped to serve quality control in production of bio-oil.

State-of-the-Art Review on the Behavior of Bio-Asphalt Binders and Mixtures.

Asphalt binder is the most common material used in road construction. However, the need for more durable and safer pavements requires a better understanding of asphalt's aging mechanisms and how its characteristics can be improved. The current challenge for the road industry is to use renewable materials (i.e., biomaterials not subjected to depletion) as a partial replacement for petroleum-based asphalt, which leads to reducing the carbon footprint. The most promising is to utilize biomaterials following the principles of sustainability in the modification of the asphalt binder. However, to understand whether the application of renewable materials represents a reliable and viable solution or just a research idea, this review covers various techniques for extracting bio-oil and preparing bio-modified asphalt binders, technical aspects including physical properties of different bio-oils, the impact of bio-oil addition on asphalt binder performance, and the compatibility of bio-oils with conventional binders. Key findings indicate that bio-oil can enhance modified asphalt binders' low-temperature performance and aging resistance. However, the effect on high-temperature performance varies based on the bio-oil source and preparation method. The paper concludes that while bio-oils show promise as renewable modifiers for asphalt binders, further research is needed to optimize their use and fully understand their long-term performance implications.

The Potential Significance of Microwave-Assisted Catalytic Pyrolysis for Valuable Bio-Products Driven from Albizia Tree

The objective of this study is to investigate the feasibility of Na2CO3 and ZSM-5 as catalysts in the microwave pyrolysis of Albizia branches. An evaluation was conducted to determine the influence of power applied, experimental time, particle size, and catalysis type and ratio on the quality and quantity of pyrolysis products. Established methods such as GC-MS, FTIR, HHV, SEM, EDX, and BET were used to characterize the properties of bio-oil and biochar produced. The results demonstrated that using both catalyst types led to a substantial enhancement in biogas production. The improvement ranged from 5% to 41% with Na2CO3 and reached 45% with ZSM-5. At a lower power level of 300 W, the bio-oil yield augmented from 28% to 40% and 53% when using ZSM-5 and Na2CO3, respectively. The GC-MS analysis revealed that the utilizing of catalysts enhanced the levels of aromatic compounds, esters, and alcohols in bio-oil, along with an increase in the higher heating value (HHV) from 19.5 MJ/kg to 22 MJ/kg and 24.2 MJ/kg using Na2CO3 and ZSM-5, respectively. Moreover, the biochar's surface area and pore volume experienced a considerable rise, going from 0.5512 m2/g and 0.00011 cm3/g to a higher value of 115.2073 m2/g and 0.0774 cm3/g when treated with Na2CO3. The data indicated that both catalyst types enhanced the generation of CH4, and CO2 was lower with ZSM-5. The utilization of catalysts improves the quality of the biofuel produced and promotes the efficiency of the process in terms of energy consumption and processing time.

Insight into catalytic effects of alkali metal salts addition on bamboo and cellulose pyrolysis

Alkali metal compounds have vital influence on biomass pyrolysis conversion. In this study, cellulose, and bamboo catalytic pyrolysis with different alkali metal salts catalysts (KCl, K2SO4, K2CO3, NaCl, Na2SO4, and Na2CO3) were investigated in the fixed-bed reaction system. The effects of cations (K+ and Na+) and anions (Cl-, SO42−, and CO32-) on the evolution properties of biochar, bio-oil, and gas products were explored under both in-situ and ex-situ catalytic pyrolysis. Results showed that alkali metal salts facilitated the yields of biochar and gases at the expense of that of bio-oil. Alkali metal chloride and sulfate showed a weaker catalytic effect, while alkali metal carbonate greatly promoted the generation of gas products and increased the condensation degree of biochar. With the addition of K2CO3 and Na2CO3, cyclopentanones content was over 50% from cellulose catalytic pyrolysis, and phenols content (mainly alkylphenols) reached over 80% from bamboo catalytic pyrolysis. Moreover, solid-solid catalytic reactions with K2CO3 and Na2CO3 catalysts had an important role in strikingly promoting conversion of pyrolysis products, and the solid-solid and gas-solid catalytic reactions with alkali metal carbonate catalysts were stronger than those with alkali metal chloride and sulfate catalysts. Furthermore, the possible catalytic pyrolysis mechanism of alkali metal salts on biomass pyrolysis was proposed, which is important to the high-value utilization of biomass.

Nickel and cobalt incorporated mesoporous HZSM-5 catalysts for biofuel production from bio-oil model compounds

Bio-oil obtained through the gasification or pyrolysis of biomass is a renewable energy source with the potential to be used in motor vehicles. However, when the properties of bio-oil are compared to crude oil, bio-oil is observed to have high oxygen content and acidity. The aim of this study is to enhance the physical properties of bio-oil and produce new alternative fuels to crude oil. For this purpose, nickel and cobalt-incorporated mesoporous HZSM-5 catalysts have been synthesized. The synthesized catalysts were characterized by X-ray diffraction, N2 adsorption–desorption, Scanning electron microscopy energy dispersive spectroscopy, Inductively coupled plasma optical emission spectroscopy, Fourier-transformed infrared spectroscopy, and thermogravimetric/differential thermal analysis. In the study, formic acid, furfural, and hydroxypropanone were used as model components. To enhance catalyst activity, nickel was loaded onto the HZSM-5 catalyst. However, during biofuel production, a significant amount of coke was formed as a by-product. Therefore, cobalt was impregnated to reduce coke formation. In the activity test studies, a conversion in the range of 77–84% was achieved with HZSM-5 catalysts. Nickel addition increased the paraffin and olefin content in the biofuel along with bio-oil conversion. The maximum paraffin selectivity (97%) was provided with the 5Ni@HZSM-5 catalyst. However, the highest biofuel selectivity (77.5%) with the minimum coke formation (4%) was observed with the 5Co-5Ni@HZSM-5. In the study, the regeneration and long-term catalytic activity were also investigated, and the results showed that 5Co-5Ni@HZSM is an attractive catalyst for biofuel production from bio-oil.

Biodiesel production from eggshells derived bio-nano CaO catalyst–Microemulsion fuel blends for up-gradation of biodiesel

The utilization of bio-oil derived from biomass presents a promising alternative to fossil fuels, though it faces challenges when directly applied in diesel engines. Microemulsification has emerged as a viable strategy to enhance bio-oil properties, facilitating its use in hybrid fuels. This study explores the microemulsification of Jatropha bio-oil with ethanol, aided by a surfactant, to formulate a hybrid liquid fuel. Additionally, a bio-nano CaO heterogeneous catalyst synthesized from eggshells is employed to catalyse the production of Jatropha biodiesel from the microemulsified fuel using microwave irradiation. The catalyst is characterized through UV–Vis, XRD, and SEM analysis. The investigation reveals a significant reduction in CO, CO2, and NOX emissions with the utilization of microemulsion-based biodiesel blends. Various blends of conventional diesel, Jatropha biodiesel, and ethanol are prepared with different ethanol concentrations (5, 10, and 20 wt%). Engine performance parameters, including fuel consumption, NOX emission, and brake specific fuel consumption, are analyzed. Results indicate that the conventional diesel/Jatropha biodiesel/ethanol (10 wt%) blend exhibits superior performance compared to conventional diesel, Jatropha biodiesel, and other blends.The fuel consumption of the conventional diesel/Jatropha biodiesel/ethanol (10 wt%) blend is measured at 554.6 g/h, surpassing that of conventional diesel and other biodiesel blends. The presence of water (0.14 %) in the blend reduces the heating value, consequently increasing the energy requirement. CO and CO2 emissions for the conventional diesel/Jatropha biodiesel/ethanol (10 wt%) blend are notably lower compared to conventional C-18 hydrocarbons and various biodiesel blends. These findings accentuate the efficacy of the microemulsion process in enhancing fuel characteristics and reducing emissions. Further investigations could explore optimizing the emulsifying agents and their impact on engine performance and emission characteristics, contributing to the advancement of sustainable fuel technologies.

Sustainable Al2O3 nanoparticles in catalytic pyrolysis: Unlocking high-yield bio-oil from Melia azedarach fruit biomass with comprehensive physicochemical analysis

The catalytic pyrolysis of Melia azedarach fruit biomass in the presence of aluminium oxide (Al2O3) nanoparticles was studied using a fixed bed reactor. Cost-effective and sustainable Al2O3 nanoparticles were employed as a catalyst in biomass pyrolysis and these nanoparticles were synthesized by using the extract of Phyllanthus emblica seeds as a reducing and capping agent. The confirmation of fabricated Al2O3 nanoparticles was analyzed by EDS, SEM and XRD characterization techniques. The potential effects of pyrolysis process parameters including catalyst dose, temperature and time were investigated. The optimized catalytic bio-oil was further characterized by FTIR spectroscopy. Moreover, physiochemical analyses were also performed to examine the bio-oil properties as fuel. This study demonstrates that catalytic bio-oil produced from Melia azedarach fruit biomass has the potential to be used as a substitute for fossil fuel for the generation of energy and industrial applications.

Optimization of Operational Parameters Using Artificial Neural Network and Support Vector Machine for Bio-oil Extracted from Rice Husk.

Bio-oil production from rice husk, an abundant agricultural residue, has gained significant attention as a sustainable and renewable energy source. The current research aims to employ artificial neural network (ANN) and support vector machine (SVM) modeling techniques for the optimization of operating parameters for bio-oil extracted from rice husk ash (RHA) through pyrolysis. ANN and SVM methods are employed to model and optimize the operational conditions, including temperature, heating rate, and feedstock particle size, to enhance the yield and quality of bio-oil. Additionally, ANN modeling is utilized to create a predictive model for bio-oil properties, allowing for the efficient optimization of pyrolysis conditions. This research provides valuable insights into the production and properties of bio-oil from RHA. By harnessing the capabilities of ANN and SVM, this research not only aids in understanding the intricate relationships between process variables and bio-oil properties but also provides a means to systematically enhance the production process. The predictive results obtained from the ANN were found to be good when compared with the SVM. Several models with different numbers of neurons have been trained with different transfer functions. R values for the training, validation, and test phases are around 1.0, i.e., 0.9981, 0.9976, and 0.9978, respectively. The overall R-value was 0.9960 for the proposed network. The findings were considered acceptable, as the overall R-value was close to 1.0. The optimized operational parameters contribute to the efficient conversion of RHA into bio-oil, thereby promoting the use of this sustainable resource for renewable energy production. This approach aligns with the growing emphasis on reducing the environmental impact of traditional fossil fuels and advancing the utilization of alternative and environmentally friendly energy sources.

Effect of Co and Ni impregnated ZSM-5 catalyst on pyrolysis products of Tithonia diversifolia: Kinetic study and thermodynamics

Addressing the need for sustainable alternative fuels amid depleting petroleum resources and environmental concerns, this study investigates the conversion of abundant and eco-friendly lignocellulosic biomass, the invasive weedy plant Tithonia diversifolia (TD), through pyrolysis to bio-oil. The influence of ZSM-5 catalysts with Ni and Co impregnation is also explored on fixed bed-pyrolytic conversion as well as employing various kinetic and thermodynamic models. Characterization techniques including XRD, SEM, and EDX confirm successful metal loading while preserving microstructure. Catalysts significantly impact product distribution, and physicochemical analysis alongside NMR and GC-MS data reveal improved bio-oil properties, including reduced O content, increased C content, and higher calorific values when catalysts are employed. Kinetic analysis suggests lower activation energies for catalytic pyrolysis (Ea∼105–154 kJ/mol) compared to non-catalytic processes (Ea∼160 kJ/mol), emphasizing the catalytic role in enhancing biomass conversion. Thermodynamic analysis further supports catalytic enhancements of biomass devolatilization. This study offers valuable perspectives on the pivotal role of catalysts in biomass conversion.

Optimizing Seaweed (Ascophyllum nodosum) Thermal Pyrolysis for Environmental Sustainability: A Response Surface Methodology Approach and Analysis of Bio-Oil Properties

This study focuses on optimizing the thermal pyrolysis process to maximize pyrolysis oil yield using marine biomass or seaweed. The process, conducted in a batch reactor, was optimized using response surface methodology and Box–Behnken design. Variables like temperature, residence time, and stirring speed were adjusted to maximize bio-oil yield. The optimal conditions yielded 42.94% bio-oil at 463.13 °C, with a residence time of 65.75 min and stirring speed of 9.74 rpm. The analysis showed that temperature is the most critical factor for maximizing yield. The bio-oil produced contains 11 functional groups, primarily phenol, aromatics, and alcohol. Its high viscosity and water content make it unsuitable for engines but suitable for other applications like boilers and chemical additives. It is recommended to explore the potential of refining the bio-oil to reduce its viscosity and water content, making it more suitable for broader applications, including in engine fuels. Further research could also investigate the environmental impact and economic feasibility of scaling up this process.

Optimization of Bio Asphalt Derived from Pyrolysis Bio Oil for Bitumen Modification

Due to inadequate crude oil supply and a rising demand for petroleum asphalt in roadconstruction, the asphalt sector faces a continuing shortage. Continous research was conducted on renewable materials such as bio-oils derived via pyrolysis from local palm oil industries. Bio-oil is currently a viable option due to its renewability, environmental friendliness, and variety of sources. Despite numerous studies indicating that biooils enhance the properties of bitumen, the research on the effects of PKS biooil on bitumen properties is minimal and needed further investigations. The application of 2,4-diphenylmethane diisocyanate (MDI) in this study is established to enhance the properties of bio-oil modified bitumen. The objectives of this study are to analyse the relationship between the percentage andratio of PKS bio-oil and 2,4-diphenylmethane diisocyanate (MDI) of the modified bitumen, its physical and chemical effects and the optimization of bio-asphalt mixture after the 2,4diphenylmethane diisocyanate (MDI) has been blended with PKS bio-oil and bitumen. PKS bio-oil and MDI were applied into the bitumen as additive and replacement of bitumen at 3%, 5% and 7% with two different ratios; 1.0:0.6 and 1.0:1.0. The functional groups of the bitumen are identified using Fourier Transform Infrared (FTIR) analysis. The result generated from FTIR analysis showed that the modified bitumen samples were slightly different when compared to the conventional bitumen regarding the functional group. Response surface methodology (RSM)was implemented to determine the statistical analysis and optimum amount of PKS bio-oil and MDI content in the bitumen, through central composite design.

Semi-continuous hydrothermal processing of pine sawdust for integrated production of fuels precursors and platform chemicals

This research reports data for the integrated obtaining of fermentable sugars (FSs), bio-oil (BO), and hydro-char (HC) – all fuel precursors – as well as platform chemicals (PCs – acetic, formic, and levulinic acid, besides furfural, and hydroxymethylfurfural) through semi-continuous hydrothermal processing of sawdust from pine wood. The influence of temperature (260, 300, and 340 °C) and the water-to-biomass ratio (25 and 50 g H2O (g biomass)−1) were the parameters considered to evaluate the mass yields, kinetic profiles, and BO properties. For FSs (and PCs), a detailed analysis considering the kinetic profiles of obtaining cellobiose, glucose, xylose, and arabinose is presented. For the conditions evaluated, a distinct behavior concerning the process parameters was observed, where 7.11 and 9.28 g (100 g biomass)−1 of FSs and PCs were synergistically obtained, respectively, after 30 min, 20 MPa, 260 °C, and 50 g H2O (g biomass)−1. Contextually, 17.59 g (100 g biomass)−1 of BO was obtained at 340 °C and the same water/biomass ratio. FTIR analysis of the BO samples suggested the presence of aldehydes, carboxylic acids, ketones, hydrocarbons, ethers as well as aromatic, alcohols, and nitrogenous compounds. Similar HC yields were achieved among the conditions analyzed, where 24.68 g (100 g biomass)−1 were obtained at 340 °C and 50 g H2O (g biomass)−1 for a higher heating value of 29.14 MJ kg−1 (1.5 times higher than the in natura biomass).

Green catalyst for clean fuel production via hydrodeoxygenation.

The development of new fuel sources to replace nonrenewable fossil fuels has received substantial attention due to the ongoing demand for fossil fuels. Biomass and raw waste materials are crucial sources to produce suitable alternative fuels instead of nonrenewable fuels and offer a greener approach. Therefore, improving the fuel properties of biooils produced from the thermochemical conversion of biomass and raw waste materials is critical as it is used as an alternative to nonrenewable fuel. Developing an economical and eco-friendly method to produce sustainable and renewable oil by improving biooil containing large amounts of phenolic compounds has become imperative. One of the most intriguing and promising technologies for refining biooil to produce renewable fuels of comparable quality to conventional fossil fuels is the hydrodeoxygenation (HDO)-based process for converting biooil to renewable fuels. This method is almost one of the best improving methods described in the literature. At this point, it is of great importance that the HDO process is carried out catalytically. Carbon materials are preferred for both designing catalysts for HDO and supporting metal nanoparticles by providing chemically inert surfaces and tunable functional groups, high surface area and active sites. The HDO of biomass and raw waste materials has significantly advanced thanks to carbon-based catalysts. In this review, the effect of the surface character and catalytic ability of the carbon support, especially prepared by the green synthesis technique, on the HDO reaction during biooil improvement is discussed. Moreover, HDO reaction parameters and recent studies have been investigated in depth. Thus, green carbon catalysts' role in clean fuel production via the HDO process has been clarified.

Fractional condensation of sawdust pyrolysis vapors: Separation of complex components, enhancement of bio-oil properties, and life cycle assessment

This study investigates the fractional condensation of multicomponent vapors obtained from the pyrolysis of sawdust in a fluidized bed reactor at 500 °C, and the resulting pyrolytic vapors which were subjected to fractional condensation using a temperature-controlled system consisting of four condensers. The objective was to assess the effectiveness of this fractional condensation system in separating complex components and enhancing bio-oil properties. The characterization of the bio-oil included evaluating pH value, total acid number (TAN), heating value, and chemical compositions. The findings revealed that the last two condensers effectively collected most of small molecular chemicals such as acetic acid, ketones, esters, alcohols, aldehydes, and water. Notably, Benzenes (benzene, toluene, and ethylbenzene) and certain types of phenols (creosol and Phenol, 2,3-dimethyl-) tended to condense in SBO 1, as their temperatures were higher than their dew points. SBO 1 exhibited the highest calorific value of 29.42 MJ/kg, whereas SBO 2 displayed the lowest acidity (1.19 mol/L) and a higher calorific value (11.38 MJ/kg) compared to SBO 3 and SBO 4. Additionally, a life cycle assessment (LCA) demonstrated that the fractional condensation method possesses economic and environmental advantages. This approach offers a promising technique for effectively separating complex components in bio-oil derived from sawdust pyrolysis, leading to improved product properties and reduced environmental impact. Consequently, these findings contribute to the advancement of sustainable biomass conversion processes and underscore the potential for optimizing the production of valuable bio-based products.

Biofuels obtained from the crambe (Crambe abyssinica) oil

Among the biofuels, bio-oil and biodiesel stand out as more sustainable alternatives to fossil fuels, and non-edible oils are an interesting alternative feedstock as there is no competition with human food. This study aimed to obtain and evaluate the physicochemical properties of bio-oils and biodiesels obtained from crambe oil (Crambe abyssinica), which is not used in human food due to the large amount of erucic acid, which has considerable toxicity. Bio-oils were obtained by thermal cracking of the oil without catalyst at three different temperatures, 400, 600, and 800 °C, and methyl and ethyl biodiesel were obtained through alkaline transesterification reaction. The chemical components of the bio-oils were determined by gas chromatography and showed the presence of hydrocarbons, alcohols, ethers, and ketones, and the absence of aromatic compounds. The physico-chemical properties were evaluated, and all bio-oils and biodiesels presented values within the required range for commercialization as biofuels, except for the acidity index. Esterification of the bio-oils improved the acidity index, and moisture helped to improve the physico-chemical properties of the bio-oil, and as CCS600 presented the highest amount of hydrocarbons, it was the most suitable for use as bio-oil.

Fast pyrolysis simulation via kinetic approach and multivariate analysis to assess the effect of biomass properties on product yields, properties, and pyrolyzer performance

Fast pyrolysis (FP) is the thermochemical conversion of biomasses and other carbonaceous materials into bio-oil (liquid), char (solid), and gas products to be used to generate heat, power, chemicals, and fuels of lower greenhouse gas emissions. Considering biomass properties highly affect the FP performance, this work used simulation and multivariate analysis tools to assess the effect of the composition of nine Brazilian biomasses on the FP energy demands, product yields, and bio-oil properties. A simulation, representing a pyrolyzer (480 °C, 1-s residence time), product recovery, and char combustion to meet FP energy demands, was built in Aspen Plus v.10 and validated against experimental data. A dataset correlating biomass compositions from 60 sources and FP outputs was obtained and analyzed, via two statistical methods, to detect similarities between feedstocks and correlate biomass inputs and process outputs. Hierarchical cluster analysis (HCA) separated the feedstocks into two main clusters: agricultural and woody biomasses. The main differences were associated with agricultural feedstocks having higher biomass H/C ratios, lower carbon and volatiles contents, and being of the CHL type (cellulose > hemicellulose > lignin), resulting in lower char and higher gas yields. As for correlations between inputs and outputs, HCA and principal component analysis (PCA) divided the parameters into five main groups: (i) biomass O/C ratio and cellulose content; (ii) bio-oil yield, heating value, and extractives content; (iii) biomass H/C ratio, hemicellulose content, and bio-oil quality metrics; (iv) ash content, char yield, and pyrolyzer heat duty; and (v) biomass lignin, volatiles, and heating value with gas yield and heating value. Several anticorrelations were also detected (e.g., bio-oil yield anticorrelated to bio-oil properties; char yield anticorrelated to gas yield). This work hopes to serve as a simplified roadmap for relationships between biomass properties and FP performance, providing guidelines for biomass selection for different bio-oil downstream applications and perspectives on future works on FP simulation.