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An attempt was made to generate gasoline-range aromatics from pyrolysis oil derived from rubberwood. Catalytic cracking of the pyrolysis oil was conducted using an HZSM-5 catalyst in a dual reactor. The effects of reaction temperature, catalyst weight, and nitrogen flow rate were investigated to determine the yield of organic liquid product (OLP) and the percentage of gasoline aromatics in the OLP. The results showed that the maximum OLP yield was about 13.6 wt%, which was achieved at 511 C, a catalyst weight of 3.2 g, and an N2 flow rate of 3 mL/min. The maximum percentage of gasoline aromatics was about 27 wt%, which was obtained at 595 C, a catalyst weight of 5 g, and an N2 flow rate of 3 mL/min. Although the yield of gasoline aromatics was low, the expected components were detected in the OLP, including benzene, toluene, ethyl benzene, and xylenes (BTEX). These findings demonstrated that green gasoline aromatics can be produced from rubberwood pyrolysis oil via zeolite cracking.

This research provides a novel approach for the determination of water content and higher heating value of pyrolysis oil. Pyrolysis oil from Napier grass was used in this study. Water content was determined with pH adjustment using a Karl Fischer titration unit. An equation for actual water in the oil was developed and used, and the results were compared with the traditional Karl Fischer method. The oil was found to have between 42 and 64% moisture under the same pyrolysis condition depending on the properties of the Napier grass prior to the pyrolysis. The higher heating value of the pyrolysis oil was determined using an oil-diesel mixture, and 20 to 25 wt% of the oil in the mixture gave optimum and stable results. A new model was developed for evaluation of higher heating value of dry pyrolysis oil. The dry oil has higher heating values in the range between 19 and 26 MJ/kg. The developed protocols and equations may serve as a reliable alternative means for establishing the actual water content and the higher heating value of pyrolysis oil.

Abstract In this study, effect of waste tire (WT) addition to cotton stalk (CS) pyrolysis is investigated with a focus on liquid co-pyrolysis yield quantity and quality. Various blend ratios (i.e. CS/WT 1:0, 4:1, 3:2, 2:3, 0:1) of the two feedstocks were experimented in a fixed bed reactor at 20 °C/min heating ramp rate up to 550 °C with 50 ml/min flowrate of nitrogen as sweeping gas. Blend ratio CS/WT (2:3) showed maximum oil yield (48 wt%) with organic phase (OP) above 78 wt% of the total liquid yield (OP + aqueous phase, AP). OP of CS/WT (2:3) along with those of CS/WT (1:0) and (0:1) were further analyzed qualitatively using analytical techniques including, FTIR, GC-MS, bomb calorimetry and elemental analyzer. Significant increase in carbon and decrease in oxygen content of the CS/WT (2:3) pyrolytic oil was observed which improved its calorific value to 41 MJ/kg. Among the three OP samples, only CS/WT (2:3) oil showed significant presence of alkanes in GC-MS results, which is, thus, associated with the synergistic effect of the co-pyrolysis process. Addition of WT to CS pyrolysis feedstock improved liquid yield and its quality, thus requiring lesser further processing for its commercial use as compared to that of CS/WT (1:0) oil. Graphical abstract Image Highlights • Co-pyrolysis of waste tire and cotton stalk was investigated for the first time. • Increased Oil and char yield found in co-pyrolysis oil; maximum for CS/WT (3:2). • CS/WT (3:2) oil showed calorific value of 41 MJ/kg, comparable to diesel. • CS/WT (3:2) oil contained higher sulfur, aldehydes and ketonic content. [ABSTRACT FROM AUTHOR]

This study aimed to produce and improve the quality of pyrolysis oil as a source of bioenergy that is made by mixing palm empty fruit bunch (EFB) with high-density polyethylene (HDPE) plastic waste. The slow co-pyrolysis method was employed, and HDPE waste and EFB were fed into the pyrolysis reactor at HDPE amounts of 0, 10, 25, 50, 75, and 100% by weight. The pyrolysis oil product was obtained by co-firing EFB with HDPE using the slow co-pyrolysis method in a fixed bed reactor at 500°C with a flow rate of 750 mL/min and a heating rate of 5°C/min. The chemical compositions of pyrolysis oil were analyzed by gas chromatographymass spectroscopy. A pyrolysis oil produced by HDPE 100 wt.% was dominated by the chemical compounds of phenols, aromatics, aliphatic, and acids, while for EFB 100 wt.% was dominated with aldehydes, acids, phenols, furan and aliphatic. The addition of HDPE reduced the amount of pyrolysis oil yield, increased the pH, reduced the viscosity, and reduced the oxygen content of the pyrolysis oil. These results proved that the HDPE affected the decrease in pyrolysis oil and the increase in gas production from co-firing HDPE and EFB using the slow co-pyrolysis method. [ABSTRACT FROM AUTHOR]

Abstract Pyrolysis is a promising technology for disposing of waste printed circuit boards (WPCBs) with organics removal and materials recovery. However, pyrolysis oil contains various hazardous and carcinogenic components, leading to difficulty to reuse and refine. Therefore, novel methods for utilizing pyrolysis oil were needed. The purpose of this study is to reuse pyrolysis oil as raw material to synthesize oil-based resin. The pyrolysis oil was produced by argon pyrolysis of WPCBs at 600 °C and temperature-controlled condensation at 100 °C. The results showed that the optimum parameters for synthesizing oil-based resin were the mole ratio of phenols in pyrolysis oil and formaldehyde of 1:0.8, synthesis temperature of 90 °C, reaction time of 2.0 h, and HCl concentration of 5.0%. Besides, the kinetic model of curing reaction was established by Kissinger and Kaelble methods, which agreed well with the experimental data. The results of SEM, TG-DTG, FT-IR, and NMR indicated that oil-based resin had the similar morphology, thermostability, functional groups and chemical structure compared with commercial resin, indicating that the oil-based resin had huge economic value. Besides, other ingredients in pyrolysis oil participated in the synthesis process of oil-based resin, resulting in the decrease of oil-based resin molecular weight. The proposed mechanism of synthesis oil-based resin can be concluded as protonation, addition and condensation polymerization. This study raises a novel method to utilize pyrolysis oil effectively, sustainably and environmentally friendly. Graphical abstract Image 1 Highlights • Pyrolysis oil was collected and separated by temperature-controlled condensation technique. • Pyrolysis oil, as raw material, was used to synthesize oil-based resin. • The structure and thermostability of oil-based resin were similar to commercial resin. • Synthesis mechanism of oil-based resin was analyze. [ABSTRACT FROM AUTHOR]

Red mud (RM) is an alkaline waste generated in the Bayer process of alumina production. In the present study red mud supported nickel catalysts (Ni/RM) were prepared at different concentrations of nickel (10, 20, 30, 40, 50, and 65 wt.%) and used to hydrodeoxygenate (HDO) pinyon-juniper (PJ) catalytic pyrolysis oil. Increasing the nickel content improved the activity of Ni/RM catalysts for HDO reactions. Maximum organic liquid yield (68.6%) was obtained when 40%Ni/RM was used. The upgraded oil had oxygen content of 1.35 wt.% and higher heating value of 45.77 MJ/kg compared to 24.88 wt.% and 28.41 MJ/kg, respectively, for the crude oil. For comparison, commercial Ni/SiO 2 -Al 2 O 3 was also evaluated in HDO experiments. The HDO oil properties obtained using 40%Ni/RM at reaction temperature of 400 °C was similar to that of commercial Ni/SiO 2 -Al 2 O 3 at reaction temperature of 450 °C. However, the organic liquid yield was much higher for 40%Ni/RM (68.6%) compared to the commercial Ni/SiO 2 -Al 2 O 3 (41.8%). The commercial Ni/SiO 2 -Al 2 O 3 produced more gas (27.6%) than the 40%Ni/RM (16.4%) and the coke yields for the commercial catalyst and Ni/RM catalyst were 7.3% and 4.2% respectively. Overall, application of Ni/RM improved HDO reactions and reduced cracking and coke formation compared to commercial Ni/SiO 2 -Al 2 O 3 . [ABSTRACT FROM AUTHOR]

Pyrolysis oil is a promising material for renewable energy through a hydrogenation process. However, the polymerization, initiated especially by pyrolysis oil water-soluble fraction (PS), is a big hurdle to hydrogenation. The types and structures of the polymerization chemicals, their polymerization mechanisms are very important for upgrading pyrolysis oil. This study firstly compared the polymerization rates of water-soluble fraction (PS) and water-insoluble fraction (PL) by accelerating aging fresh PS and PL at different temperatures (80 °C, 90 °C, 100 °C and 110 °C) for 24 h and at 110 °C for different durations (12 h, 24 h, 36 h, 48 h and 60 h), respectively. The thermogravimetric and differential thermogravimetry analysis results showed that PS polymerized much more rapidly than PL. Then, PS polymerization was further investigated by evaluating the changes in its physical properties (water content, viscosity and element content) and chemical compositions (gas chromatography and liquid chromatogram) before and after aging. The results showed that hydroxy aldehydes and ketones (especially glycoaldehyde, hydroxyacetone and levoglucosan), dicarbonyl compounds (especially succindialdehyde) and α, β-unsaturated carbonyl compounds (especially 3-methyl-2-cyclopenten-1-one and dehydrate resultants of some aldol condensation products) were mainly responsible for PS polymerization. [ABSTRACT FROM AUTHOR]

This article studies co-pyrolysis of combustible municipal solid waste (MSW) without/with additives (CaO, CuCl2, zeolite powder, and MnO2). Co-pyrolysis of different MSW components mixing and adding additives in co-pyrolysis could change yield of oil, high heating value (HHV), and products distribution. The yield of oil increases noticeably, but HHV decreases with ratio (sawdust: paper) increasing. Moreover, the yield of phenols increases. After adding fabric, the yield of acids and alcohols increases and that of aldehyde decreases. The yield of oil decreases after adding CaO and MnO2, and HHV of co-pyrolysis increases after adding CaO, zeolite powder, and MnO2. Adding MnO2 has the most impact on the decrease of aldehyde, and adding CuCl2 has the biggest effect on phenol reducing. The yield of ketone is affected most greatly by adding CaO. [ABSTRACT FROM AUTHOR]

Researchers examined how nozzle design influences the combustion and emissions of a 10 kW, pure fast pyrolysis oil (FPO) flame from a swirl burner within an insulated combustor using an internally mixed air-blast nozzle. No other studies are known that conducted a detailed investigation of the effect of nozzle design on the combustion and emissions of a pure FPO spray flame. FPO (also called bio-oil or pyrolysis liquid biofuel) is a biofuel made from waste wood, but its properties, especially its high water content, make efficient combustion challenging. Combustion experiments showed how carbon monoxide (CO) emissions, nitric oxide (NO) emissions, carbonaceous residue, flame stability and nozzle coking were influenced by the nozzle's mixing chamber diameter and outlet number/diameter, angle and total area. Ultimately, an optimized nozzle was designed that achieved a self-sustaining FPO flame with excellent stability, low emissions and low coking; it also operated under "cold-start" conditions and at steady-state conditions, did not require a pilot flame to maintain a stable, seated flame. The results show that with careful nozzle design, FPO is able to perform very effectively in burners and can therefore help to facilitate the replacement of fossil fuels. [ABSTRACT FROM AUTHOR]

The study investigated potential of scrap tire and sugarcane bagasse as co-pyrolysis feedstock with a focus on liquid yield. Two raw materials were fed to fixed-bed reactor in various mixing ratios. The experiments were carried out at 500 °C with heating rate of 20 °C/min and Nitrogen (flowrate: 50 mL/min) was used as carrier gas. Sugarcane bagasse/scrap tire 1:3 produced highest liquid yield (49.7 wt% against 42.1 wt% of pure sugarcane bagasse), which was then characterized for physical and chemical properties using different chromatographic and spectroscopic analytical techniques. Significant synergistic effects were indicated by the quality and quantity of the co-pyrolysis liquid yield. The optimum feedstock mix produced oil with calorific value of 41 MJ/kg with lesser viscosity as compared to pure sugarcane bagasse pyrolysis oil. Co-pyrolysis oil showed high potential to be used as feedstock for fuel production after required processing. [ABSTRACT FROM AUTHOR]

In this study, microwave-assisted co-pyrolysis of high ash Indian coal and rice husk is investigated to evaluate the yield and quality of the pyrolysis oil, and to understand the interactions during co-pyrolysis. Microwave co-pyrolysis experiments were conducted in a bench scale unit, and the effects of various parameters such as microwave power (420 W and 560 W), coal:rice husk ratio, and feed:susceptor (graphite) ratio on product yields and oil composition were thoroughly evaluated. Oil yield was not significantly affected by microwave power and feed:susceptor ratio for a particular coal:rice husk ratio. The oil yields were 11 ± 2 wt%, 15 ± 2 wt%, 18 ± 2 wt%, 21 ± 2 wt% and 26 ± 2 wt% for 100:0, 75:25, 50:50, 25:75 and 0:100 wt./wt. coal:rice husk, respectively, at both microwave powers, and followed an additive effect with increase in rice husk amount in the mixtures. Pyrolysis oil contained monoaromatic hydrocarbons, naphthalene derivatives, aliphatic hydrocarbons and phenolic derivatives. The interactions between coal and rice husk pyrolysis intermediates were evidenced in the form of enhanced yields of polyaromatic hydrocarbons with a concomitant reduction in yield of methoxy phenols. Pyrolysis oil from coal had highest heating value (36–38 MJ kg −1 ) due to the presence of aliphatic hydrocarbons, while that from rice husk had the lowest heating value (28–30 MJ kg −1 ) due to high oxygenate content. The heating values of co-pyrolysis oils were in the range of 30–36 MJ kg −1 . Hydrogen constituted a major fraction in the pyrolysis gases, and the addition of rice husk to coal promoted the evolution of CO. [ABSTRACT FROM AUTHOR]

Neutralization of the bio-oil pH has been shown to generate a neutralized bio-oil aqueous phase (NBOAP) that includes most of the acidic components and a neutralized bio-oil organic phase (NBOOP) that includes hydrophobic organics, such as phenols. NBOOP can be used for fuel production, while NBOAP can be fed to microbial electrolysis cells (MECs) for hydrogen production. After pH neutralization, some organic acidic components remain in NBOOP. This work is focused on capturing acidic compounds from NBOOP through water extraction and electrosorption, and demonstrating hydrogen production via MECs. Capacitive deionization (CDI) is proven effective in capturing ions from NBOOP-contacted water and NBOAP via electrosorption. Captured acidic compounds enable the MEC application to effectively produce renewable hydrogen. Chemical oxygen demand (COD) removal of 49.2%, 61.5%, and 60.8% for 2, 4, and 10 g/L-anode/day loading were observed, corresponding to a total COD degradation of 0.19 g/L, 0.79 g/L, and 1.3 g/L, respectively. A maximum hydrogen productivity of 4.3 L-H 2 /L-anode/day was obtained. Major compounds in the water phase such as fatty acids, sugar derivatives, furanic and phenolic compounds were converted to hydrogen with an efficiency of 80–90%. This approach may lead the entire biomass pyrolysis process to be an overall carbon-neutral process. [ABSTRACT FROM AUTHOR]

Pyrolysis oil of rubber seed oil (RSO) was upgraded by methyl esterificationusingSO 4 2− /ZrO 2 solid acid as catalyst. The activity and reusability of SO 4 2− /ZrO 2 solid acid were investigated and the experiment indicated that the esterification rate could reach 99.62% and was still above 95% in the third reaction. The component of SO 4 2− /ZrO 2 solid acid changed little after the third used. The properties of the obtained biofuel were studied and the results showed they were superior to pyrolysis oil and biodiesel, and similar to 0 # diesel. The methyl esterification reaction kinetics was researched. The kinetics calculation indicated that the reaction order of the methyl esterification is 1.058, and Arrhenius equation can be expressed as k 1 = 7.711 × 10 6 e - 47.913 RT . [ABSTRACT FROM AUTHOR]

Rigid polyurethane (PU) foams are widely used for instance in building insulation. Two component systems comprising of a polyol as component A and a diisocyanate as component B are generally applied. Both components are produced from fossil oil resources. The liquid products from fast pyrolysis of biomass contain a large variety of organic compounds with OH functional groups. This gives rise to the idea to substitute the polyol component in PU foams with such biomass based intermediates. Pyrolysis condensates derived from woody and herbaceous biomass were dried and samples of PU foams were produced with varying amounts of condensate substituting the polyol component. Especially the foams made from condensates produced from straw showed good insulation properties, which were expressed as low thermal conductivity. Here, with a substitution degree of 80% a thermal conductivity of 0.0283 Wm −1 K −1 was achieved, which was 8% lower than for the foams produced from commercial components (0.0308 Wm −1 K −1 ). Preliminary results for the measurement of compressive strength indicated that the required value of 150 kPa can easily be achieved, especially with a high degree of substitution. These results show a high potential for the application of bio-based intermediates in the building sector. Further research on other properties is necessary, but the main requirements for thermal conductivity are already met without optimization of the catalyst/stabilizer system. [ABSTRACT FROM AUTHOR]

Solvent extraction of valuables compounds from pyrolysis oil is a promising way for biorefineries optimization, and the design of such operations requires accurate thermodynamic models based on experimental data. Liquid-liquid equilibria (LLE) were investigated at atmospheric pressure and 298.15, 303.15 and 313.15 K between pyrolysis oil compounds in aqueous phase and organic solvents. New liquid –liquid equilibrium data were measured involving seven typical pyrolysis oil organic compounds (acetic acid, acetol, furfural, guaiacol, methanol, phenol and propanal), water and two potential extraction solvents (Toluene and Isopropyl acetate). These new datasets together with literature LLE data have been correlated with UNIQUAC and NRTL models. Both compositions and solutes partition coefficients have been successfully correlated with those models. [ABSTRACT FROM AUTHOR]

This work presents a study on intermediate pyrolysis of the organic fraction of municipal solid waste (OFMSW) and characterisation of organic liquid product (pyrolysis oils) with particular focus on aging and rheological characteristics. The feedstock was a real municipal waste sample received from a local waste treatment plant. Shredded into small particles, it contained a high amount of moisture (51.2%) and ash (17.4%). A pilot-scale intermediate pyrolysis system was used to process the material. The process mass balance showed that the yield pyrolysis oil was 10.6%. GC-MS and FTIR experiments showed that the accelerated aging (80 °C for 24 hours) did not cause an obvious change in the liquid chemical composition, but led to a significant reduction in the solids and moisture contents. The dynamic viscosity tests demonstrated that the intermediate pyrolysis oil derived from OFMSW is a non-Newtonian fluid. The dynamic viscosity of the pyrolysis oil reduced with the increase of temperature or shear rate, which can be modelled by WLF function and the Carreau model, respectively. A shear rate-temperature superposition method was proposed to construct the viscosity master curve at a wide range of shear rate, where WLF function was employed to model the shear rate-temperature shift factor. The accelerated aging caused an obvious reduction in dynamic viscosity, resulting from the decomposition of the semisolid organic agglomerates in the solids content during the aging of the OFMSW intermediate pyrolysis oil. The relatively high viscosity and reduced viscosity after aging of the OFMSW pyrolysis oil has indicated its potential for application as a substitute of the light fraction in the bitumen for road construction. [ABSTRACT FROM AUTHOR]

Mo (content ranging from 0 to 18.8 wt%) is used as an additive in Ni‐containing sol‐gel derived catalysts NiCuMo/SiO2 for the hydrotreatment of guaiacol as a model compound in biomass derived pyrolysis liquids. The catalysts had a high Ni loading, from 39 to 51 wt%, promoted by copper with an atomic ratio Cu/Ni close to 0.12. The experiments were done in autoclave at 320 °C, at a hydrogen pressure of 9 MPa. Addition of molybdenum results in an increase in activity of the catalyst, accompanied with an increase in selectivity towards the deoxygenation reactions. This is attributed to the formation of solid solutions NiMo(Cu) and 4+ and 5+ charge states of Mo on the catalyst surface. Moreover, an increased mean metal particles size is observed at higher Mo loading, due to the weakening of the interaction between the active component (Ni) and the stabilizer (SiO2) in the presence of Mo. [ABSTRACT FROM AUTHOR]

Biomass as a renewable energy source is an alternative to fossil fuels. Due to its lower energy density compared to fossil fuels, different ways of converting biomass into an energy-dense fuel are sought after. Fast pyrolysis of biomass into pyrolysis oil represents such method, allowing wider substitution of fossil fuels. Pyrolysis is an energy-intensive process but its efficiency can be improved by integration of pyrolysis reactor into a combined heat and power plant. In this study environmental analyses are conducted on the production of 50 000 tons of pyrolysis oil from wood to substitute for heavy fuel oil. The pyrolysis oil is produced either in a stand-alone reactor or as an integrated part of a combined heat and power plant. The combined heat and power plant is wood and peat fueled, producing of 820 GWh of energy. The cradle-to-grave emissions of CO 2 -eq, NO x , SO 2, and PM are calculated by using two methods: 1) life cycle assessment and 2) the Tool for Sustainability Impact Assessment. Reductions in environmental loads of over 75% in (fossil) CO 2 -eq and over 90% in NO x , SO 2, and PM can be achieved when heavy fuel oil is replaced by pyrolysis oil. The pyrolysis is 20% more efficient if integrated with CHP production. The potential reductions vary several percent between the applied methods because of different system boundaries. Nevertheless, integrating the pyrolysis reactor into a combined heat and power plant appears as the best option irrespective of the method used. Extending the system boundaries with the life cycle inventories results in significant increases of emissions in many processes; however, combustion in plants has a dominant role in overall emissions but is not subject to the boundary extensions, and thus, the totals of emissions between the methods are nearly the same. [ABSTRACT FROM AUTHOR]

A process model of a 2000 metric ton per day eucalyptus Tail Gas Reactive Pyrolysis (TGRP) and electricity generation plant was developed and simulated in Pro/II software for the purpose of evaluating its techno-economic viability in Brazil. Two scenarios were compared based on operational conditions in the country: a single biomass to bio-oil TGRP production facility and a distributed/satellite processing that consists of several small TGRP production facilities with aggregate capacity similar to the single one, both feeding into one centralized electricity generation plant. The selling price at the breakeven point of the electricity generated via TGRP was estimated to be US$0.34 and US$0.62 per kWh for the single and the distributed scenarios respectively, considering a 10-year payback period. The single capacity pyrolysis and electricity generation facility is found to have better economic benefits over the distributed plants of small sizes under the current conditions in Brazil. The results therefore indicate that pyrolysis of eucalyptus wood for electricity in a single facility cannot be competitive with the current electricity cost in Brazil (US$0.08–0.13/kWh) at present time. Considering auxiliary benefits such as climate change and carbon credits, plus the continuous increasing in the electricity market price in Brazil, both scenarios could be competitive in the future. [ABSTRACT FROM AUTHOR]

The effect of the blend ratio and reactor temperature on the gasification characteristics of pyrolysis oil (PO) and black liquor (BL) blends with up to 20 wt% PO was studied in a pilot-scale entrained-flow gasifier. In addition to unblended BL, three blends with PO/BL ratios of 10/90, 15/85, and 20/80 wt% were gasified at a constant load of 2.75 MWth. The 15/85 PO/BL blend was used to investigate the effect of temperature in the range 1000–1100 °C. The decrease in fuel inorganic content with increasing PO fraction resulted in more dilute green liquor (GL), and a greater portion of the feedstock carbon ended up in syngas as CO. As a consequence, the cold gas efficiency increased by about 5%-units. Carbon conversion was in the range 98.8–99.5% and did not vary systematically with either fuel composition or temperature. Although the measured reactor temperatures increased slightly with increasing PO fraction, both unblended BL and the 15% PO blend exhibited largely similar behavior in response to temperature variations. The results from this study show that blending BL with the more energy-rich PO can increase the cold gas efficiency and improve the process carbon distribution without adversely affecting either carbon conversion or the general process performance. [ABSTRACT FROM AUTHOR]

Chemical looping of iron oxides has emerged as a promising approach to produce hydrogen with inherent gas separation. In this work, we use sol-gel-prepared Fe2O3/MgAl2O4 as an oxygen carrier to produce hydrogen from biomass pyrolysis oil. The results showed that 950 8C was the optimum gasification temperature to achieve a high carbon conversion and gas yield. At this temperature, we produced hydrogen by chemical looping. However, the produced hydrogen was polluted severely by CO and CO2 because of coke formation during reduction. To solve this problem, we adjusted the reduction atmosphere by adding steam, which was an effective method to enhance the hydrogen purity. At a steam-to-oil ratio of 1.5, the purity of hydrogen reached 96% in contrast to 84% without steam. In the presence of steam, we also found a more stable porosity, which led to improved cyclic performance. Our current results demonstrate an approach to enhance hydrogen purity and material recyclability. This can be extended to improve other thermochemical hydrogen- production processes. [ABSTRACT FROM AUTHOR]

Abstract: Lignocellulosic biomass conversion into value‐added platform chemicals in the non‐toxic, water‐tolerant Lewis acid, and water solutions bears the hallmark of green chemistry. Lactic acid derived from biomass is an important chemical building block for biodegradable polymers such as polylactide. Herein, a universal method of converting lignocellulosic sugars into lactic acid using catalytic amount of water‐stable Lewis acid La(OTf)3 is demonstrated. The lignocellulosic sugars studied in this work include 1) pyrolytic sugars from pyrolysis oil, and 2) sugars derived from ionic liquid (IL)‐pretreated biomass. Under moderate conditions (250 °C, 1 h), levoglucosan (major pyrolytic sugar), glucose, and xylose were converted into lactic acid with carbon‐based molar yields of 75, 74, and 61 %, respectively. Furthermore, roughly 49 mol % (based on levoglucosan) and 74 wt % (relative to pretreated biomass) of lactic acid were obtained from the conversion of pyrolytic sugars and sugar‐rich fraction after lignin removal from switchgrass, respectively. To our knowledge, this is the first reported conversion of pyrolytic sugar into lactic acid by chemocatalysis and also lignocellulosic sugars are converted into lactic acid without hydrolysis. This approach could potentially be extended to other lignocellulosic sugars after simple removal of lignin from biomass pretreatment, rendering moderate to high yields of lactic acid. [ABSTRACT FROM AUTHOR]

The utilization of plastic solid wastes for sustainable energy production is a crucial aspect of the circular economy. This study focuses on pyrolysis as an effective method to convert this feedstock into renewable drop-in fuel. To achieve this, it is essential to have a comprehensive understanding of feedstock composition, pyrolysis process parameters, and the physicochemical characteristics of the resulting fuel, all correlated with engine combustion parameters. Considering this full value chain, this study provides the first unbiased and up-to-date benchmark of polypropylene and polystyrene pyrolysis oils (PPO and PSO) produced in an industrial-grade batch reactor. The pyrolysis process was optimized to achieve ultra-high liquid yield levels of 92% for PPO and 98% for PSO with minimum energy consumption. After post-processing, blending with diesel, and normative fuel analytics, combustion/emission tests involving 20 species preceded under fully controllable conditions using a state-of-the-art single-cylinder research engine. The fuel analysis results revealed significant disparities between the properties of PPO and PSO. PPO exhibited a diverse carbon structure, resulting in very low density and high volatility. On the other hand, PSO was predominantly composed of aromatics, leading to low viscosity and poor auto-ignition properties. Engine tests showed that PPO blends exhibited combustion characteristics similar to diesel, while PSO blends exhibited significant differences, particularly during the premixed combustion stage attributed to pilot injection. Following the combustion response, the addition of PPO had minimal impact on emissions, while PSO acted as an emission enhancer, resulting in over twofold increase in particulate matter at high loads. Consequently, PSO showed elevated carbon monoxide and hydrocarbon emissions due to the higher contribution of aromatics. Ultimately, this study challenges the prevailing perception of plastic-derived fuels as "dirty". By implementing feedstock segregation to minimize polystyrene content, it is possible to achieve a fossil substitute level of 40% while meeting all emission and safety regulations for diesel engines with a minimum economic burden. [Display omitted] • Fast pyrolysis in batch reactor produced high-yield of oils from plastic. • A blend of 40% plastic oil with diesel showcases its feasibility as a drop-in fuel. • The combustion of polypropylene oil exhibits negligible effects on emissions. • Polystyrene oil shows a tendency to misfire and increases particulates emissions. [ABSTRACT FROM AUTHOR]

In this experiment, different combinations and blends based on 50% biodiesel and 50% pyrolysis oil were prepared to create 4 fuel samples for all tests. These samples were provided to the test engine operated on the conventional mode and homogeneous charge compression-ignition (HCCI) mode aiming to evaluate the performance, emission, and combustion characteristics of these modes. In the HCCI mode, a steady flow of 3 L per minute of compressed natural gas (CNG) was injected together with the air. As a result, preheated 50% Pongamia biodiesel/50% plastic pyrolysis oil combined with enriched CNG for the HCCI mode was found to be superior to those of other fuels according to performance, combustion, and emission characteristics although brake thermal efficiency was slightly lower than the conventional diesel engine. In addition, the performance and emission parameters of the HCCI engine were also predicted by using three machine learning models such as Decision Tree, Random Forest, and Support Vector Regression. Finally, Random Forest and Support Vector Regression approaches were recommended to predict the operation parameters of the HCCI engine with an accuracy level as high as nearly 99% in most instances, except for HC and CO with 80% and 90% of accuracy levels, respectively. [Display omitted] • Performance, combustion, emission of HCCI engine under dual-fuel mode were analyzed. • CNG-enriched HCCI ran on biodiesel/pyrolysis oil blends under dual-fuel mode. • Dual-fuel HCCI mode exhibited better performance and lower NOx emissions. • DT, RF, and SVR models were used to predict the operating parameters of test engine. • SVR and RF models performed with 99% of accuracy in most of the instances. [ABSTRACT FROM AUTHOR]