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1.
Bioresour Technol ; 331: 124934, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33798864

RESUMO

This study investigates the potential of producing graphene oxide (GO) from biomass via green (comparatively) processing and the impact of graphitization temperature on GO quality. Our findings show that it is possible to convert biomass into highly pyrolytic biochar, followed by shear exfoliation to produce few-layer GO. However, pyrolysis temperature is key in ensuring that the biochar is suited for effective exfoliation. Low temperatures (<1000 °C) would preserve undesirable heterogenous, complex cellular structure of biomass whilst excessive temperatures (≥1300 °C) result in uncontrolled melting, coalescence and loss of functional groups. Results show 1200 °C to be the optimum graphitization temperature for miscanthus, where the resultant biochar is highly aromatic with sufficient functional groups to weaken van der Waals forces, thus facilitating exfoliation to form 6-layer GO with specific surface area of 545.3 m2g-1. This study demonstrates the potential of producing high quality, fit-for-purpose graphene materials from renewable sources.


Assuntos
Grafite , Pirólise , Biomassa , Carbono , Carvão Vegetal , Temperatura Alta , Temperatura
2.
J Chromatogr A ; 1644: 462087, 2021 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-33819678

RESUMO

For analytical purpose, thermal desorption is now used in gas chromatographs developed to analyse the chemical composition of planetary environments. Due to technical constraints, the thermal desorption cannot be as finely controlled as in the laboratory resulting in possible thermal alteration of the adsorbents used. For these reasons, the influence of heat on physical and chemical properties of various adsorbents, either used or that could be used in gas chromatographs for space exploration, is studied. If the adsorbents made of carbon molecular sieves and graphitised carbon black that were tested show a very high thermal stability up to 800°C, the porous polymers tested are highly degraded from a minimum temperature that depends on the nature of the polymer. Poly-2,6-diphenylphenylene oxide is shown to be the more thermally robust as it is degraded at higher temperatures, confirming it is currently the best choice for analysing organic molecules with a space instrument. Finally, the products of degradation of the porous polymers tested were analysed after heating the porous polymers at 400 °C and 800 °C. They were identified and listed as potential contaminants of analyses performed with this type of adsorbent. If the exposure to the higher temperature produces numerous organic compounds, mainly aromatic ones, a few ones are also detected at the lower temperature tested, meaning they should be considered as potential contaminants. Again poly-2,6-diphenylphenylene oxide should be preferred because it releases less organic compounds, the structure of which is completely specific to the adsorbent composition.


Assuntos
Cromatografia Gasosa/métodos , Voo Espacial , Temperatura , Adsorção , Gases/análise , Polímeros/química , Pirólise , Termogravimetria , Fatores de Tempo , Volatilização
3.
Bioresour Technol ; 332: 125040, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33831790

RESUMO

The higher heating value (HHV) and exergy of ultrasound-assisted deep eutectic solvent pretreated watermelon rind (WMR) biomass were investigated. Thereafter, the co-pyrolysis of the WMR biomass and coal blends was studied. The pyrolysis kinetics and thermodynamic parameters of the WMR-coal blends were determined using four isoconversional models (Flynn-Wall-Ozawa, Kissinger-Akahira-Sunose, Friedman and Starink). The HHVs of the pretreated WMR ranged between 12.73 and 19.28 MJ/kg, while the exergy value for the raw and pretreated WMR were 16.08 and 21.55 MJ/kg, respectively. The lower heating value related exergy had the greatest influence on the overall exergy of the WMR. The values of the pre-exponential factor showed variations in wide range, and the change in entropy of the system displayed both negative and positive entropies. The activation energy and enthalpy varied directly with the amount of coal in the blends. Amongst the isoconversional model methods, Friedman model was the best predictor of the kinetic parameters.


Assuntos
Citrullus , Pirólise , Biomassa , Calefação , Cinética , Solventes , Termodinâmica , Termogravimetria
4.
Bioresour Technol ; 332: 125115, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33839512

RESUMO

This study was devoted to proposing an effective experimental method based on bio-oil composition inversion for understanding biomass pyrolysis vapor evolution in four-staged condensers. The effective length of each condenser was 200 mm. The evolution curves and heat maps of condensable vapors in the whole multi-staged condensing field were provided by Logistics model fitting. With changing condition from "365-345-325-305" to "345-325-305-285", the condensing efficiency of the first condenser increased by 100% but that of the third condenser decreased by 80%. Under condition "365-345-325-305", the largest recovery rate of water was observed at 400 mm away from multi-staged condensing field entrance while that of eugenol was observed at 50 mm away from the entrance, which explained that water was primarily recovered by the second and third condensers whereas eugenol was recovered by the first condenser, and verified the remarkable effect of fractional condensation on the separation of water and high-boiling phenols.


Assuntos
Temperatura Alta , Pirólise , Biocombustíveis , Biomassa , Gases , Água
5.
Bioresour Technol ; 332: 125068, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33849751

RESUMO

Hydrothermal pretreatment (HTP) (Hot water extraction (HWE) and steam pretreatment) and pyrolysis have the potential to liquefy lignocellulosic biomass. HTP produces hydrolysate, consisting mainly of solubilized hemicellulose, while pyrolysis produces aqueous pyrolysis liquid (APL). The liquid products, either as main products or by-product, can be used as anaerobic digestion (AD) feeds, overcoming shortcomings of solid-state AD (SS-AD). This paper reviews HWE, steam pretreatment, and pyrolysis pretreatment methods used to liquefy lignocellulosic biomass, AD of liquefied products, effects of inhibition from intermediate by-products such as furan and phenolic compounds, and pretreatment tuning to increase methane yield. HTP, focusing on methane production, produces less inhibitory compounds when carried out at moderate temperatures. APL is a challenging feed for AD due to its complexity, including various inhibitory substances. Pre-treatment of biomass before pyrolysis, adaptation of microorganism to inhibitors, and additives, such as biochar, may help the AD cultures cope with inhibitors in APL.


Assuntos
Lignina , Metano , Anaerobiose , Biocombustíveis , Biomassa , Lignina/metabolismo , Pirólise
6.
Environ Sci Technol ; 55(9): 6373-6385, 2021 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-33844510

RESUMO

Algae pyrolytic bio-oil contains a large quantity of N-containing components (NCCs), which can be processed as valuable chemicals, while the harmful gases can also be released during bio-oil upgrading. However, the characteristics of NCCs in the bio-oil, especially the composition of heavy NCCs (molecular weight ≥200 Da), have not been fully studied due to the limitation of advanced analytical methods. In this study, three kinds of algae rich in lipids, proteins, and carbohydrates were rapidly pyrolyzed (10-25 °C/s) at different temperatures (300-700 °C). The bio-oil was analyzed using a Fourier transform ion cyclotron resonance mass spectrometer equipped with electrospray ionization, and the characteristics and evolution of nitrogen in heavy components were first obtained. The results indicated that the molecular weight of most heavy NCCs was distributed in the 200-400 Da range. N1-3 compounds account for over 60% in lipid and protein-rich samples, while N0 and N4 components are prominent in carbohydrate-rich samples. As temperature increases, most NCCs become more aromatic and contain less O due to the strong Maillard and deoxygenation reactions. Moreover, the heavier NCCs were promoted to form lighter compounds with more nitrogen atoms through decomposition (mainly denitrogenation and deoxygenation). Finally, some strategies to deal with the NCCs for high-quality bio-oil production were proposed.


Assuntos
Nitrogênio , Pirólise , Biocombustíveis , Biomassa , Temperatura Alta , Óleos Vegetais , Polifenóis
7.
Bioresour Technol ; 331: 125013, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33773414

RESUMO

With the aims of exploring the effectiveness of Cu(II) adsorption performed by cow manure biochars (CMBCs) for the treatment and recycling of livestock wastes, the physicochemical characteristics and Cu(II) adsorption behaviors of CMBCs at various pyrolysis temperatures (T) were analyzed. CMBCs displayed surface heterogeneity and the dominant Cu(II) adsorption reactions were chemical adsorption, including mineral co-precipitation and cations exchange, was account for 93.75% - 97.01% of the adsorption contribution. Pearson correlation analysis and quantitative analysis showed that the adsorption capacity of co-precipitation (Qcp) and cations exchange (Qci) were significantly positively correlated with ash content and cations exchange capacity (p < 0.01), respectively. The quantitative relationships between total adsorption capacity (Qt), Qcp or Qci and T are Qt = 54.01 + 0.39exp(0.0051 T), Qcp = 71.80-101.91exp(-0.0024 T), Qci = 12.25 + 311.73exp(-0.0093 T) and Qt = 0.93 Qci + 0.91 Qcp + 7.70.


Assuntos
Esterco , Pirólise , Adsorção , Animais , Bovinos , Carvão Vegetal , Feminino , Temperatura
8.
Bioresour Technol ; 331: 124955, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33774570

RESUMO

Superheated steam (SHS) has been used as a carrier gas for pressurized steam torrefaction, steam explosion or pyrolysis, but is barely used as a heat source. However, SHS is superior in thermal capacity and heat transfer coefficient resulting in even heating and fast heating rates. Therefore, this work applied SHS as the sole heat source for torrefaction at ambient pressure. A setup was specially designed and capable of heating wood shavings at a rate >120 °C•min-1. Solid products were analyzed in many aspects and demonstrated the enhanced organics conversion owing to SHS torrefaction. Torrefied biomass was comparable to slow pyrolysis char in fuel quality and superior to that of conventional torrefactions. Moreover, SHS torrefaction was super-timesaving. A coal-like product (HHV of 27.84 MJ•kg-1) was achieved in only 15 min at 350 °C. Overall, SHS torrefaction boosted biomass densification and gaveriseto greater production efficiency.


Assuntos
Temperatura Alta , Vapor , Biomassa , Pirólise , Temperatura , Madeira
9.
Bioresour Technol ; 330: 124975, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33770733

RESUMO

Valorization of biomass to olefin or aromatics harbours tremendous practical value due to growing concerns about sustainable production of chemicals. Herein, the olefin or aromatics yields of ex-situ catalytic pyrolysis of pine can be regulated by impregnating Sn on hollow-structured ZSM-5 (M-ZSM-5) and microporous ZSM-5 catalysts in fixed-bed reactor, respectively. Results showed that Sn/ZSM-5 catalyst simultaneously increased medium acidic sites and maintained strong acidic sites, which obtained the maximum carbon yield of aromatics (33.77%) due to enhanced cracking and deoxygenation reactions. In addition, Sn boosted alkylation between olefin and aromatics, generating more alkylbenzene. In contrast, Sn/M-ZSM-5 catalyst produced the highest olefins carbon yield (12.39%) because the reduction of strong acidic sites and microporous volume inhibited the olefin aromatization. Moreover, olefins were easier to desorb from Sn/M-ZSM-5 due to the enhanced mass transfer ability, which weakened the alkylation reactions. The synergistic effect harbours great significance to manipulate the distribution of products.


Assuntos
Alcenos , Pirólise , Biomassa , Catálise , Estanho
10.
Bioresour Technol ; 329: 124874, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33647605

RESUMO

This study investigated on the co-pyrolysis of microalgae Chlorella vulgaris and high-density polyethylene (HDPE) waste mixtures which was performed with three types of catalysts, namely limestone (LS), HZSM-5 zeolite, and novel bi-functional LS/HZSM-5/LS. Kissinger-Kai (K-K) model-free method was coupled with Particle Swarm Optimization (PSO) model-fitting method using the thermogravimetric experimental data. A global sensitivity analysis was carried out using Latin Hypercube Sampling and rank transformation to assess the extent of impact of the input kinetic parameters on the output results. Furthermore, a thermodynamic analysis was performed to obtain parameters such as enthalpy change (ΔH), Gibb's free energy (ΔG), and entropy change (ΔS). The activation energy (EA) of the microalgae Chlorella vulgaris and HDPE binary mixture were found to be lower upon the addition of catalysts. Among the catalyst used, bi-functional LS/HZSM-5 catalyst exhibited the lowest EA (83.59 kJ/mol) and ΔH (78 kJ/mol) as compared to LS and HZSM-5 catalysts.


Assuntos
Chlorella vulgaris , Catálise , Cinética , Plásticos , Pirólise , Termogravimetria
11.
Bioresour Technol ; 329: 124856, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33652191

RESUMO

In this study, the sulfonic group was introduced to prepare high-performance Eucommia ulmoides lignin-based biochar, which was used to remove tetracycline hydrochloride. The BET area (2008 m2 g-1) of sulfonated biochar was twice that of unmodified biochar. Through XRD and Raman analysis, the synergetic pyrolysis mechanism of the sulfonic group in the formation of the porous structure was discussed. Sulfonated biochar had excellent adsorption performance for tetracycline hydrochloride (Qm: 1163 mg g-1), while the adsorption performance of unmodified biochar was about only one-fourth (Qm: 277.7 mg g-1) of that. The adsorption of tetracycline hydrochloride by the sulfonated biochar was spontaneously endothermic and conformed to the Langmuir isotherm model. The adsorption process was confirmed by pseudo-second-order kinetic model. Moreover, the sulfonic group on the sulfonated biochar significantly promoted the formation of the hydrogen bond and greatly improved the adsorption performance.


Assuntos
Eucommiaceae , Poluentes Químicos da Água , Adsorção , Carvão Vegetal , Cinética , Lignina , Pirólise , Tetraciclina/análise , Poluentes Químicos da Água/análise
12.
Bioresour Technol ; 329: 124907, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33706175

RESUMO

To further explain effects of pyrolysis temperature on physicochemical properties of corn stalk pellet biochar from a new perspective, various lab physicochemical analysis methods combining microcomputed tomography were used to characterize biochar in this study. The results showed that at pyrolysis temperatures from 300 °C to 800 °C, yield of biochar decreased logarithmically with increasing pyrolysis temperature (T); changes of proximate and elemental compositions all showed significant differences, but the change rules were not consistent; high temperature pyrolysis biochar had high stability, high hardness and was convenient for storage and transportation; the proportions of hydroxyl group and amino group were highest in BC800 and BC600, respectively, contributing to the adsorption and removal of pollutants; BC400 had the best combustion performance; X-ray mean attenuation coefficient (XMAC) showed the following correlations, namely, XMAC = 0.003*ln(T-285.329) + 0.011 (R2 = 0.904) and XMAC = -0.031*(VM/100) + 0.021*(Ash/100) + 0.027 (R2 = 0.915). Above results provide important basic data support for development of corn stalk pellet biochar.


Assuntos
Pirólise , Zea mays , Adsorção , Carvão Vegetal , Temperatura , Microtomografia por Raio-X
13.
Molecules ; 26(4)2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33671928

RESUMO

Metal organic framework (MOF)-derived carbon nanostructures (MDC) synthesized by either calcinations or carbonization or pyrolysis are emerging as attractive materials for a wide range of applications like batteries, super-capacitors, sensors, water treatment, etc. But the process of transformation of MOFs into MDCs is time-consuming, with reactions requiring inert atmospheres and reaction time typically running into hours. In this manuscript, we report the transformation of 1,4-diazabicyclo[2.2.2]octane, (DABCO)-based MOFs into iron nitride nanoparticles embedded in nitrogen-doped carbon nanotubes by simple, fast and facile microwave pyrolysis. By using graphene oxide and carbon fiber as microwave susceptible surfaces, three-dimensional nitrogen-doped carbon nanotubes vertically grown on reduced graphene oxide (MDNCNT@rGO) and carbon fibers (MDCNT@CF), respectively, were obtained, whose utility as anode material in sodium-ion batteries (MDNCNT@rGO) and for EMI (electromagnetic interference) shielding material (MDCNT@CF) is reported.


Assuntos
Carbono/química , Fontes de Energia Elétrica , Fenômenos Eletromagnéticos , Estruturas Metalorgânicas/química , Nanoestruturas/química , Nitrogênio/química , Sódio/química , Fibra de Carbono/química , Eletrodos , Íons , Nanoestruturas/ultraestrutura , Nanotubos de Carbono/ultraestrutura , Espectroscopia Fotoeletrônica , Pirólise , Análise Espectral Raman , Difração de Raios X
14.
J Environ Manage ; 287: 112292, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33690014

RESUMO

This paper presents the experimental results obtained after incorporating the recovered Carbon Black (rCB) produced in an industrial-scale waste tire pyrolysis plant into a Natural Rubber (NR) formulation. The purpose of this study is to increase the technical knowledge on the use of rCB as a sustainable raw material in the rubber industry. The rCB and virgin Carbon Black (vCB) (ref. N550) under study were characterized using elemental and proximate analyses, X-Ray Fluorescence (XRF), Fourier Transform Infrared (FTIR) spectroscopy, and Scanning Electron Microscopy (SEM) were used, and different measures, including the Brunauer-Emmett-Teller (BET) surface area (SBET), particle size distribution (PSD), specific gravity, and pH, were estimated. The effect of rCB incorporation on the rheological, thermal, structural, and mechanical properties of the NR composites was assessed and compared to those obtained with vCB alone. The NR composites were prepared using different loads of vCB (20, 30, 40, and 50 phr), which was also replaced with rCB at different proportions (0, 50, and 100%). According to the characterization results, rCB offers lower reinforcement properties than vCB, which is attributable to its higher volatile matter and ash contents, higher apparent PSD, lower presence of acidic functional groups, and lower SBET. Despite this, interesting performances can be achieved when rCB is partially incorporated into the formulations or by increasing its load in the composites. For instance, when 50% of vCB was replaced with rCB, the values of the aforementioned properties were found to be between those obtained with the NR composites prepared with vCB and rCB. In addition, when increasing the rCB loading, some properties matched the behavior exhibited by vCB alone, thus compensating for the low reinforcement properties of rCB. These results are expected to provide an important impetus to move towards circular economy strategies having very positive impacts from the sustainable perspective.


Assuntos
Pirólise , Fuligem , Carbono , Resíduos Industriais , Borracha
15.
J Environ Manage ; 287: 112269, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33711665

RESUMO

The limited literature on the cost of various recycling methodologies for thermoset composites sets the background of this work, focusing mainly on the identification of an upper and lower economic value of glass fibre recovered from wind turbine blades recycling. The study briefly reviews the materials used by various original equipment manufacturers (OEM) for wind turbine blades. Successively, it provides an overview of the various recycling methods with interest in recovered materials, mechanical and physical properties, which are used, for estimating a maximum expected value. All recycling processes show a negative effect on mechanical properties with strength loss between 30% and 60%. Process energy demands are reviewed, and considerations are set forward to estimate the minimum cost of operating mechanical, pyrolysis and fluidized bed plants in Germany. Ultimately, current applications of recovered material and related markets are explored. Through interviews and secondary data, it is highlighted that despite the lower mechanical properties, grinded material finds applications in traditional processes, cement kilns and new products. It is also found that pyrolysed fibres can be used as insulation material and oils can be easy to distil. Pyrolysis is a relatively expensive process, thereby, distillation of the oils and energy recovery are necessary enablers towards commercial viability. Mechanically grinded material presents the lowest process cost with ca. €90/tonne, thus, below landfilling and incineration and falling within the attention of private businesses. Numerous markets are available for recovered materials from wind turbine blades, primarily for grinded products and secondly for pyrolysed glass fibre.


Assuntos
Pirólise , Reciclagem , Alemanha
16.
Carbohydr Polym ; 260: 117827, 2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-33712167

RESUMO

Alginates, a kind of naturally occurring polysaccharides, have been exploited for functional materials owing to their versatility, sustainability, nontoxicity, and relatively low cost. Inherent flame retardancy is one of the most attractive features of alginates, as it enables the high-value-added utilization of alginates for eco-friendly flame-retardant materials. Now, the influence of metal ions on the flame retardancy and pyrolysis behaviors of alginates has been systematically studied; besides, the applications of alginates for flame-retardant materials have been greatly developed, such as for preparing flame-retardant fibers, fabrics, aerogel composites, and foams, as well as serving as a component or modifier of functional coatings, hybrids, and additives. This review will give an overview of the recent progress and the prospects of using alginates in flame-retardant fields, which can guide the design of bio-based flame retardants and benefit the further development of more diverse applications of alginates.


Assuntos
Alginatos/química , Retardadores de Chama/análise , Géis/química , Metais/química , Polímeros/química , Pirólise , Viscosidade
17.
Environ Pollut ; 279: 116934, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-33744627

RESUMO

The COVID-19 pandemic has exerted great shocks and challenges to the environment, society and economy. Simultaneously, an intractable issue appeared: a considerable number of hazardous medical wastes have been generated from the hospitals, clinics, and other health care facilities, constituting a serious threat to public health and environmental sustainability without proper management. Traditional disposal methods like incineration, landfill and autoclaving are unable to reduce environmental burden due to the issues such as toxic gas release, large land occupation, and unsustainability. While the application of clean and safe pyrolysis technology on the medical wastes treatment to produce high-grade bioproducts has the potential to alleviate the situation. Besides, medical wastes are excellent and ideal raw materials, which possess high hydrogen, carbon content and heating value. Consequently, pyrolysis of medical wastes can deal with wastes and generate valuable products like bio-oil and biochar. Consequently, this paper presents a critical and comprehensive review of the pyrolysis of medical wastes. It demonstrates the feasibility of pyrolysis, which mainly includes pyrolysis characteristics, product properties, related problems, the prospects and future challenges of pyrolysis of medical wastes.


Assuntos
Resíduos de Serviços de Saúde , Humanos , Pandemias , Pirólise
18.
Waste Manag ; 125: 77-86, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33677181

RESUMO

Pyrolysis of furfural residue (FR) was performed at 450-850 °C by employing a fluidized bed pyrolyzer (FBP). Addition of Kaolin and Ca-bentonite to FR considerably increased the condensate yields. The highest condensate yield (24.96 wt%) was obtained at 650 °C when Ca-bentonite was added. Fourier transform infra-red (FTIR) spectrum of pyrolysis oil (PO) indicated that catalysts promoted generation of alkene, amine, sulfate, sulfonyl chloride and oxime during pyrolysis. Gas chromatography mass spectrometry (GC-MS) demonstrated that catalysts significantly increased the content of furfural and phenol in PO and the maximum phenol content (15.36%) was achieved in PO650-3 for CaO. The quite low relative proportion (RP) of ammonia nitrogen in liquid indicated that the dominant form of nitrogen in liquid was not ammonia nitrogen. CaO had the ability to reduce H2S release, indicating significant sulfur retention capacity. The maximum RP (99.29%) of chlorine in bio-char (BC) was observed with the addition of CaO, showing its strong chlorine retention capacity.


Assuntos
Furaldeído , Pirólise , Biocombustíveis/análise , Catálise , Gases , Temperatura Alta
19.
Waste Manag ; 125: 145-153, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33689990

RESUMO

Waste tire was heat-treated to prepare sulfur self-doped chars via pyrolysis and activation processes. Pyrolytic waste tire chars were activated at different temperatures (600 °C, 800 °C, 1000 °C, and 1200 °C) with K2FeO4 additive ratios (mass ratio of K2FeO4 to char) being 0.5, 1, 2, and 3, respectively. The effective activation occurred over 600 °C with K2FeO4 additive ratios over 0.5. The strongest activation occurred at 1000 °C with K2FeO4 additive ratio of 3, and the specific capacitance increased to 129.5 F/g at 1 A/g, which was six times higher than that without K2FeO4. The activation mechanism revealed that higher K2FeO4 additive ratio promoted the transformation of large aromatic ring systems (≥6 rings) to small ones and smaller pores formation. When K2FeO4 additive ratio was less than 2, high ratio not only promoted alkyl-aryl C-C bonds formation, but also inhibited sulfur enrichment with S 2p3/2 (sulphide bridge) converting to S 2p5/2 (sulphone bridge). But when the ratio was further increased, slight decomposition of alkyl-aryl C-C bonds with the promoted conversion of S 2p5/2 to S 2p3/2 was witnessed. Furthermore, higher activation temperature promoted the conversion of aromatic ring systems and alkyl-aryl C-C bonds to form ordered graphitic structures. S 2p3/2 was enriched before 800 °C, but both S 2p3/2 and S 2p5/2 were released at higher temperature. Formation of smaller pores was promoted before 1000 °C, but the char structure was then destroyed to form larger pores when temperature was further increased.


Assuntos
Temperatura Alta , Pirólise , Enxofre , Temperatura
20.
Environ Pollut ; 278: 116836, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33689952

RESUMO

The remarkable journey of progression of mankind has created various impacts in the form of polluted environment, amassed heavy metals and depleting resources. This alarming situation demands sustainable energy resources and approaches to deal with these environmental hazards and power deficit. Pyrolysis and co-pyrolysis address both energy and environmental issues caused by civilization and industrialization. The processes use hazardous waste materials including waste tires, plastic and medical waste, and biomass waste such as livestock waste and agricultural waste as feedstock to produce gas, char and pyrolysis oil for energy production. Usage of hazardous materials as pyrolysis and co-pyrolysis feedstock reduces disposal of harmful substances into environment, reducing occurrence of soil and water pollution, and substituting the non-renewable feedstock, fossil fuels. As compared to combustion, pyrolysis and co-pyrolysis have less emission of air pollutants and act as alternative options to landfill disposal and incineration for hazardous materials and biomass waste. Hence, stabilizing heavy metals and solving the energy and waste management problems. This review discusses the pyrolysis and co-pyrolysis of biomass and harmful wastes to strive towards circular economy and eco-friendly, cleaner energy with minimum waste disposal, reducing negative impact on the planet and creating future possibilities.


Assuntos
Pirólise , Eliminação de Resíduos , Biomassa , Substâncias Perigosas , Incineração
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