By-product Of Pyrolysis Research Articles

Infiltration of direct-spun carbon nanotube articles

A key step towards realizing the promise of macroscopic carbon nanotube (CNT) articles in high-performance structural applications is polymer infiltration into the porous CNT structure, which improves stress transfer and promotes long-term material integrity. However, infiltration is often found to be sub-optimal - a significant impediment to the scaling and adoption of CNT-article composites that has thus far received little systematic attention. In this study, a unique combination of inverse gas chromatography (IGC) and a statistical thermodynamic model is used to accurately quantify the energetic driving force for infiltration into CNT articles for the first time. This is measured to have a very low value. Using gas chromatography-mass spectroscopy, IGC analysis and electron microscopy, this low energy is found to result from near-complete surface coverage by non-graphitic pyrolysis byproducts. The surface energy is improved by plasma treatment as confirmed by IGC analysis. The effects of the surface treatment and modifications to the porous structure on the infiltration rate of model liquids are studied by optical imaging. Accurate surface energy measurements and image analysis are coupled to shed light on the critical parameters in these CNT articles that dictate the infiltration physics, which can be tuned to maximize the rate and extent of space filling.

Biochars derived from by-products of microalgae pyrolysis for sorption of gaseous H2S

KOH-modified biochars derived from by-products of microalgae pyrolysis were prepared to adsorb gaseous H2S. Influences of various parameters (e.g., mass ratio between KOH and biochars, and adsorption temperature) on desulfurization performance were investigated. Kinetics/mechanisms of H2S adsorption, and reutilization of spent adsorbents for capturing gaseous Hg0 were also explored. Results exhibited that KOH modification greatly improved the desulfurization performance of biochars via improving the pore structures of biochar and increasing the surfaces oxygen-containing group. The modified biochars (CK2 and SK2) achieve optimal desulfurization performance, with an adsorption capacity of 59.10 mg/g for CK2 and 42.30 mg/g for SK2, respectively. Adsorption temperature showed a double effect on desulfurization. S0 and sulfate were successfully detected on biochar surface after adsorption via XPS and XRD analysis, indicating that chemical adsorption occurred in the H2S adsorption. Kinetic study showed that physical adsorption governed the H2S adsorption process, and mass transfer was the main control step of the desulfurization process. The spent adsorbents (i.e., spent containing-sulfur biochars) could capture efficiently Hg0 in gas and shown good competitiveness as compared with commercial activated carbon.

Fast pyrolysis of elephant grass: Intensification of levoglucosan yield and other value-added pyrolytic by-products

The aim of this research is to intensify levoglucosan yield from elephant grass by fast pyrolysis and show the potential of elephant grass as a biomass to obtain other value-added byproducts. The biomass was subjected to acetic acid pretreatment at 90 °C prior to pyrolysis. The experiments were carried out in a GC/MS coupled with a pyroprobe reactor at 350–600 °C, resulting in more than 30 formed compounds including pyrolytic sugars, organic acids, ketones, aldehydes, furans, and phenolic compounds. The acid treatment contributed to hemicellulose and lignin reduction, of approximately 2 and 2.4 times, respectively. Consequently, the cellulose relative content in the biomass increased from 25.7% to 66.6%, contributing to an 11-fold increase in the levoglucosan content, compared to untreated biomass. Acid treatment prior to fast pyrolysis resulted essentially in the: a) removal of alkali and alkaline earth metals, confirmed by ICP, and b) biomass morphological changes confirmed by SEM, as well as probable chemical and structural changes suggested by FTIR qualitative analysis. In both cases, these results can explain levoglucosan yield increase and other changes in value-added byproduct formation observed after pyrolysis. In addition, the liquid fraction showed a reduction in the formation of oxygenated compounds, which are responsible for several undesirable properties of bio-oil as biofuel. Thus, the attained results can contribute to the development of the elephant grass agribusiness chain for energy purposes.

Products from pyrolysis textile sludge as a potential antibacterial and alternative source of fuel oil

The aim of this study was to evaluate the potential use of textile sludge and its pyrolysis by-products in the energy sector and the potential use of the oily phase fraction (OPF) as an antibacterial against selected microorganisms. Characterization assays were carried out, for the raw textile sludge (TS) and pyrolysis by-products, as pH variation, elemental analysis, metal content, FTIR, and higher heating value. The OPF was also fractionated using a column chromatography with different solvents (n-hexane, dichloromethane, and methanol) as mobile phases, and then each fraction was analyzed by gas chromatography coupled with mass spectrometry (GC-MS). Due to the biocide activity of the OPF, antibacterial assays were carried out against Escherichia coli (ATCC 700336), Staphylococcus aureus (ATCC 25923), Pseudomonas aeruginosa (ATCC BAA-47), and Klebsiella pneumoniae (ATCC 10031). From the results, it was observed that: the obtained OPF was able to high inhibition performance in the bacterial growth at concentrations >17 mg mL -1 ; and the TS, OPF, and tar (TRF) presented higher heating value > 20 MJ kg -1 . The results show the potential use of OPF as a low-cost antibacterial agent and the feasibility of using textile sludge and pyrolytic oil fractions as an alternative source of fuel for energy generation. The textile sludge was submitted to pyrolysis, and its by-products (char and liquid fractions) were evaluated as potential alternative source of fuel for energy generation. Bio-oil was also evaluated as an antibacterial against selected microorganisms. • Pyrolysis conditions. • Characterization of the raw sludge and the pyrolysis by-products. • Bio-oil was fractionated in liquid column and the fractions were analyzed by GC/MS. • Evaluation of pyrolysis by-products and raw sludge as an alternative fuel. • Evaluation of bio-oil as a potential low-cost antibacterial agent.

Synthesis of an environmentally friendly binding material using pyrolysis by-products and modified starch binder for slow-release fertilizers

Biochar-based slow-release fertilizers (BSRFs) are vital for the development of eco-friendly and sustainable agriculture. Considerable attention has been given to enhancing the efficiency of fertilizers (EEFs) by appropriate modification or binding to reduce nutrient waste and improve the slow-release effect on the growth of plants. In this study, sustained binding materials were presented for BSRF synthesis, including pyroligneous acids (PA), bio-oil (BO), and modified starch binder (MSB). The results show that the release ratio of phosphorus from PA + BO+MSB was 4.7%, 15.2%, and 21.2% slower than that of PA, BO, and MSB alone, respectively. The BSRFs were characterized by SEM, XRD, FT-IR, XPS, and EDS, and the release kinetic outcome revealed that PA + BO+MSB contributed to the formation of a satisfactory structure in the BSRFs. The MSB viscosity significantly influences the slow-release performance and accumulation of N, P, and K nutrients. Moreover, economic assessments showed that PA + BO+MSB exhibited the lowest cost.

Pyrolysis-Based Municipal Solid Waste Management in Poland—SWOT Analysis

Poland’s management of municipal waste, which amounts to over 13 million tons/year, is not efficient—about 60% of the waste is subjected to recovery processes, about 20% of all municipal waste is converted into energy, and almost 40% is landfilled. The authors of this article recognize the potential of pyrolysis as a method of the thermal processing of waste allowing the potential of the energy contained in the waste to be utilized. Pyrolysis is an economically attractive alternative to incineration, with a significantly lower environmental impact, allowing efficient waste management and the use of pyrolysis by-products in the energy sector (pyrolysis gas), or in the building materials sector (biochar). Despite so many advantages, this method is not employed in Poland. The aim of the paper is to indicate a recommended strategy for the application of pyrolysis in Poland as a method of the thermal processing of municipal solid waste. SWOT (strengths, weaknesses, opportunities, threats) analysis was used as a research method. In the first step, on the basis of the literature review, the factors which may affect the use of pyrolysis in Poland were identified. In the second step, five experts evaluated the weights of those factors and the interactions between them. The products of the weights and interactions allowed, in accordance with SWOT analysis methodology, the most desirable strategy of pyrolysis application in Poland to be determined, which turned out to be an aggressive one. This means that pyrolysis as a thermal waste processing method should be implemented on a large scale in Poland to improve the indicators of municipal waste management.

Valorizing the Carbon Byproduct of Methane Pyrolysis in Batteries

Valorizing the Carbon Byproduct of Methane Pyrolysis in Batteries

Pyrolytic Biochar Precursors from Agricultural and Forest Residues Towards Toluene Removal in Wastewater Applications: Fast Pyrolysis By-Products Upgrading and Alternative Co-Production Process Scenario

Pyrolytic Biochar Precursors from Agricultural and Forest Residues Towards Toluene Removal in Wastewater Applications: Fast Pyrolysis By-Products Upgrading and Alternative Co-Production Process Scenario

Exploring the potential neurotoxicity of vaping vitamin E or vitamin E acetate

Serious adverse health effects have been reported with the use of vaping products, including neurologic disorders and e-cigarette or vaping product use-associated lung injury (EVALI). Vitamin E acetate, likely added as a diluent to cannabis-containing products, was linked to EVALI. Literature searches were performed on vitamin E and vitamin E acetate-associated neurotoxicity. Blood brain barrier (BBB) penetration potential of vitamin E and vitamin E acetate were evaluated using cheminformatic techniques. Review of the literature showed that the neurotoxic potential of inhalation exposures to these compounds in humans is unknown. Physico-chemical properties demonstrate these compounds are lipophilic, and molecular weights indicate vitamin E and vitamin E acetate have the potential for BBB permeability. Computational models also predict both compounds may cross the BBB via passive diffusion. Based on literature search, no experimental nonclinical studies and clinical information on the neurotoxic potential of vitamin E via inhalation. Neurotoxic effects from pyrolysis by-product, phenyl acetate, structurally analogous to vitamin E acetate, suggests vitamin E acetate has potential for central nervous system (CNS) impairment. Cheminformatic model predictions provide a theoretical basis for potential CNS permeability of these inhaled dietary ingredients suggesting prioritization to evaluate for potential hazard to the CNS.

Spray atomization characteristics of biomass pyrolysis tar: Influence of methanol addition, temperature, and atomization pressure

Pyrolysis tar, the main by-product of low-temperature biomass pyrolysis, can potentially replace fossil fuels and help achieve carbon neutrality. The efficient atomization of pyrolysis tar is a prerequisite for clean combustion. In this study, an experimental platform was built to explore the influence of methanol addition, temperature, and atomization pressure on the spray atomization of pyrolysis tar. The results indicated that methanol addition was more effective at improving the pyrolysis tar fluidity than heating at temperatures lower than 40 °C. There was no significant change in the composition of pyrolysis tar after adding methanol. The atomization results showed that the optimal experimental parameters were 12 wt% methanol, 80 °C, and an air pressure of 0.6 MPa. The addition of methanol had little effect on the spray angle, which was mainly affected by the atomization pressure. The r value was used to measure the degree of the effect of process parameters, and the degree of the effect increased with the r value. For the spray droplet size, the r values of methanol addition, temperature, and air pressure were 57.3, 9.1, and 8.8. In contrast, for the spray angle, the r values were 3.6, 2.4, and 9.8, respectively.

C18-functionalized Fe3O4/SiO2 magnetic nano-sorbent for PAHs removal from water

Magnetic sorbents represent very promising materials for environmental applications due to their simple synthesis, separability in a magnetic field, low toxicity, wide range of possible modifications, and usability in heterogeneous systems. We report on the synthesis, characterization, and application of magnetically separable Fe3O4/SiO2 sorbent surface-modified with octadecyl chains (C18). Preparation of Fe3O4 cores by co-precipitation from Fe2＋ and Fe3＋ chlorides in an alkaline aqueous solution was followed by SiO2 shell synthesis and functionalization with C18. Fe3O4, Fe3O4/SiO2, and Fe3O4/SiO2-C18 samples were characterized by SEM, TOC, XRD, BET, and tested for purification of water contaminated by various polycyclic aromatic hydrocarbons (PAHs). Since PAHs are formed as by-products of pyrolysis, a rapidly evolving technology for transformation of waste into green chemicals, there is a need for efficient sorbents suitable for PAHs removal from the environment. The use of Fe3O4/SiO2-C18 for adsorption of 16 different PAHs has not yet been reported. The adsorption was examined by gas chromatography with mass spectrometry and studied using molecular modeling. Comparison of adsorption efficiency η for Fe3O4, Fe3O4/SiO2, and Fe3O4/SiO2-C18 revealed a positive effect of C18. When averaging all Fe3O4/SiO2-C18 doses tested (1–8 g/L), η > 80% and > 90% was found for 14 and 7 PAHs, respectively, out of a total of 16 tested PAHs. The highest η values were found for medium-heavy PAHs (178.2–228.2 g/mol). Exhibiting high efficiency and average capacity of ∼1μg/g, the Fe3O4/SiO2-C18 is suitable for pre-concentration purposes of PAHs in analytical sample extractions from water.

Nitrogen-doped activated carbons derived from microalgae pyrolysis by-products by microwave/KOH activation for CO2 adsorption

Two types of nitrogen-doped activated carbons derived from microalgae pyrolysis by-products by microwave/KOH activation (thermal/KOH activation as comparison) were synthesized to separate CO2 from flue gas. The nitrogen-doped activated carbons were characterized, and CO2 adsorption performance, kinetics and thermodynamics and regeneration ability on nitrogen-doped activated carbons were studied. Results display that microwave/KOH activation contributes to developed pore structure and abundant active functional groups, resulting in high CO2 adsorption capacities. CO2 adsorption processes over nitrogen-doped activated carbons (C-NMK(2)/chlorella and S-NMK(2)/spirulina) are controlled via external mass transfer and are mainly physisorption. CO2 adsorption capacities of nitrogen-doped activated carbons by microwave/KOH activation are obviously better than thermal/KOH activation. The maximal CO2 adsorption capacities of C-NK(2) and S-NK(2) by thermal/KOH activation are 3.44 mmol/g and 3.09 mmol/g (25 °C), respectively, while the maximal CO2 adsorption capacities of C-NMK(2) and S-NMK(2) by microwave/KOH activation reach 4.21 mmol/g and 3.57 mmol/g (25 °C), respectively. The improvement of CO2 adsorption capacity (microwave vs. thermal) is attributed to more developed pore structure. CO2 adsorption capacities of C-NMK(2) and S-NMK(2) only reduce slightly (less than 10 %) after ten regeneration tests, showing excellent cyclic stability. The results offer beneficial reference for the application of low-cost microalgae nitrogen-doped activated carbons for CO2 separation, and effectively realize the utilization of microalgae pyrolysis by-products.

Influence of Pyroligneous Acid on Fermentation Parameters, CO2 Production and Bacterial Communities of Rice Straw and Stylo Silage

Carbon dioxide (CO2) is a primary greenhouse gas and the main cause of global warming. Respiration from plant cells and microorganisms enables CO2 to be produced during ensiling, a method of moist forage preservation applied worldwide. However, limited information is available regarding CO2 emissions and mitigation during ensiling. Pyroligneous acid, a by-product of plant biomass pyrolysis, has a strong antibacterial capacity. To investigate CO2 production and the influence of pyroligneous acid, fresh stylo, and rice straw were ensiled with or without 1% or 2% pyroligneous acid. Dynamics of the fermentation characteristics, CO2 production, and bacterial communities during ensiling were analyzed. Pyroligneous acid increased the lactic acid content and decreased the weight losses, pH, ammonia-N content, butyric acid content, and coliform bacterial numbers (all P < 0.05). It also increased the relative abundance of Lactobacillus and decreased the relative abundances of harmful bacteria such as Enterobacter and Lachnoclostridium. Adding pyrolytic acids reduced the gas production, especially of CO2. It also increased the relative abundances of CO2-producing bacterial genera and of genera with the potential for CO2 fixation. In conclusion, adding pyroligneous acid improved the fermentation quality of the two silages. During ensiling, CO2 production was correlated with bacterial community alterations. Using pyroligneous acid altered the bacterial community to reduce CO2 production during ensiling. Given the large production and demand for silage worldwide, application of pyroligneous acid may be an effective method of mitigating global warming via CO2 emissions.

Experimental study on feeding characteristics of conical bottom pneumatic spout feeder for biomass pyrolysis

To solve the inherent problems that bridging and agglomeration phenomena of biomass feedstock existing in the biomass pyrolysis process, and the pyrolysis by-product can not be recycled reasonably, a novel conical bottom pneumatic spout feeder was designed, which used a conical hopper, pressure chamber and inclined spout pipe and utilized the gravitational potential energy of biomass to achieve a continuous and stable feeding process. Various tests were conducted experimentally to obtain the feeding characteristics of the new feeder, where different parameters of biomass and spout pipes were included. The results showed that a high moisture content and a large particle diameter had negative impacts on the feeding. The inclined angle and inner diameter (ID) of the spout pipe at the optimal feeding effect were 30°, 20mm, respectively, and the optimal range of spout gas velocity was 5-7m/s. A physical model of gas-solid flow was established based on Ergun and Bernoulli equations, and the mathematical correlation of the feeding rate was obtained. The deviation between the calculated values and the experimental values was within ±7%, indicating that the model had a high predict accuracy.

Screening and Ranking Methodology Applied to Biochars Aimed at Acidic and Calcareous Sandy Soil Improvement

The application of biochar (the by-product of biomass pyrolysis), as a soil amendment has been accepted as a sustainable solution to improve soil quality. The current study aims to establish a decision support tool for characterizing, ranking, and selecting biochars of different origins for soil improvement, thereby contributing to the development of a systematic approach, which lacks in the existing literature.The development of a Multi-Criteria Decision Support Approach applying a banded and weighted rating and scoring system allowed the selection and ranking of various biochars suitable for improving sandy soils before application. First, 14 selected, different biochar products (produced from industrial by-products, herbaceous, wood-based and manure-based feedstocks) were characterized with several physicochemical, biological and ecotoxicological methods taking into account both the technological and the environmental efficiency aspects of biochar utilization. Then, a system for the assessment and ranking of biochars for acidic, and calcareous neutral sandy soil improvement was developed, which could be flexibly adapted to different soil problems as well. Based on their performance in the tests, scores from (−5) to (+5) were assigned to each biochar. As a result, the grain husks and paper fiber sludge biochar was ranked as the most suitable for both acidic and neutral calcareous sandy soil improvement, with 55 and 43 scores, respectively (from the maximum 100). The applicability of this innovative multicriteria scoring-ranking system, as a tool for potential biochar users, was verified in microcosms and field-scale experiments, demonstrating the positive influence of this biochar on the acidic sandy soil.

Recovery of Ionic Liquid from Aqueous Phase Pyrolytic Oil: A Simulation Using ASPEN HYSYS V10

Aqueous phase pyrolytic oil is generally considered less important and often discarded as a pyrolysis by-product due to lack of specific applications. Although, recent studies have proposed production of hydrogen via catalytic aqueous and steam reforming from this stream, however, these processes require complex system. Imidazole is one of the major components of aqueous phase pyrolytic oil which can be converted into different products. This study presents a new valorisation strategy of aqueous phase pyrolytic oil into renewable ionic liquid through simulation. A steady state process simulation for recovery of imidazole from aqueous phase pyrolytic oil and subsequent conversion into ionic liquid was developed using ASPEN HYSYS V10 ®. Effects of different operating variables such as feed flow rate, composition and temperature on the imidazole recovery, ionic liquid yield and composition were investigated. The simulation results revealed that high yield of renewable ionic liquid with physicochemical properties comparable to that of commercially available ionic liquids can be produced from aqueous phase pyrolytic oil. This product can be utilised for biomass refining since ionic liquid have been reported to selectively remove hemicellulose and lignin in many biomass related applications such as pre-treatment and characterization.

Lignocellulose pyrolysis by-products as an underestimated source of chemicals: separation and characterisation

Within the valorisation of lignocellulosic biomass, it is important not only to isolate the dominant compounds, but also to extract and purify the by-products. In this study, birch (Betula pendula) chips were used as feedstock in fast pyrolysis to obtain and purify levoglucosenone. Levoglucosenone was isolated by distillation, but the residual by-products were further fractionated by solid-phase extraction with a sequence of solvents: water, methanol, acetone and hexane. The focus was on the separation of the distillation residues and valorisation of levoglucosenone production by-products in order to promote a biorefinery approach to biomass pyrolysis. Combination of different analytical techniques—UHPLC-UV/MS, SEC-UV, FTIR, GC-MS and Py-GC-MS—has shown significant qualitative differences in the obtained fractions of the distillation residues, enabling a comprehensive characterisation and evaluation of the pyrolysis by-products.

A three-stage heating system of dual-fuel controlled by negative feedback for fluidized bed fast pyrolysis

To ensure the reduction of unnecessary consumption of thermal energy, precise control of the pyrolysis temperature, reasonable use of pyrolysis by-products, and the self-supply of thermal energy in the pyrolysis process, a novel three-stage heating system for pyrolysis was designed, which used liquefied petroleum gas (LPG) and non-condensable gas (NCG) as dual fuels. The programmable logic controller (PLC) adopted the negative feedback to individually control the four key temperatures in the heating system, and finally realized the precise control of pyrolysis temperature. In the case of only LPG to combust, the heating and reaction characteristics of the experimental apparatus were obtained in the initial experiment. The results showed that the heating system had the basis for NCG to replace LPG to combust. From the perspective of saving energy and reducing consumption energy, when LPG and NCG combusted simultaneously and the yield of liquid product was 59%, the self-supply of thermal energy can be realized, that was, reaching the point of energy balance. When the pyrolysis temperature was 500 °C and the packing height was 100 mm/50 mm, the peak value of the combustion gas replacement rate reached 78.2%, and the ideal working conditions were realized at this time.

A comprehensive study on by-products of food processing industry pyrolysis using a thermobalance reactor coupled to GC-FID/TCD: Mass, atomic and energy balances, thermokinetic modeling, product distribution, and characterization

The current study aims to investigate the pyrolysis process and bioenergetic potential of pineapple peel and passion fruit shell wastes (by-products of food processing industry) by the physicochemical characterization, mass balance, energy balance, atomic balance, and kinetic study. Pyrolysis was performed at low heating rates (5, 10, and 15 °C min−1) in an argon atmosphere in a thermobalance reactor coupled to GC-FID/TCD. The pyrolysis showed a higher yield of non-condensable gases that had low calorific value (<3.51 MJ kg−1gas) due to the high concentration of CO2, which are from oxygenated functional groups. The fraction of solid and liquid had calorific value greater than 26.84 MJ kg−1, where biochar is favorable for application in steam gasification due the ash composition. For the energy balance, it was observed that the pyrolysis condition in the current study provided little exothermic characteristics for global process of both biomasses. Thermogravimetric data showed two main regions of pyrolysis (active pyrolysis and passive pyrolysis). The high release of CO and CO2 with high weight loss rate were observed in active pyrolysis (<370 °C), while the release of CH4 and H2 with low weight loss rate were observed in passive pyrolysis (>370 °C). For the kinetic study, it was assumed the presence of four pseudo-components, which were extracted from thermogravimetric data using the deconvolution tool. The kinetic parameters obtained from the Vyazovkin method, compensation effect, and mater plot could satisfactorily describe the pyrolysis process of both biomasses, with a determination coefficient greater than 0.9.

New horizons in the application of a neglected biomass pyrolysis byproduct: A marked simultaneous decrease in ammonia and carbon dioxide emissions

During the process of biochar production, large amounts of wood vinegar (WV) are obtained as a byproduct, and the objective of this study was to investigate the efficiency of this byproduct in reducing the ammonia (NH3) pollution and greenhouse gas emissions that are associated with animal husbandry. Special attention was given to the potential of WV in bringing about NH3 and carbon dioxide (CO2) emission reductions, and the dynamic mean of the concentrations of NH3 and CO2 as well as the effect of WV on several environmental indicators were investigated. For the first time, a positive correlation was observed between the removal efficiencies of NH3 and CO2 and WV concentration. Specifically, when the concentration of WV was 7%, the highest removal efficiencies for NH3 and CO2 were obtained (79.1 ± 1.8 and 54.3 ± 4.9%, respectively). These results confirmed that acidification using WV could be a promising approach for the synergistic mitigation of NH3 and CO2 emission in swine houses. The results of this study also clarify the connection between the products of biomass pyrolysis, livestock sector pollution, and gas emission reduction. Therefore, it is expected that the results of this study will generate a global discussion regarding the removal of the pollutants that are associated with animal housing facilities and these three fields to the end of promoting green development and cleaner production globally.