Wood Tar Research Articles

Hierarchical porous carbon derived from wood tar using crab as the template: Performance on supercapacitor

Owing to intrinsic structural limitations, it is difficult to control the pore structure of biomass to synthesize hierarchical porous carbons (HPCs) to achieve high supercapacitor performance. As an inevitable by-product of the thermochemical conversion of biomass, wood tar exhibits good thermoplasticity and high-carbon content, and can be used as an alternative carbon source for biomass to prepare HPCs. To improve the utilization of wood tar, a facile synthetic route is proposed for preparing HPCs, based on a natural biological template method coupled with KOH activation. The HPCs possess favorable features in terms of high solid-carbon yield, high oxygen content (~9 at%), large specific surface areas (626.43–2489.62 m2 g−1), and an interconnected hierarchical porous structure, which greatly improved wettability and synergistically enable the construction of high-performance supercapacitors in aqueous and organic systems. The optimized HPC electrode exhibits a specific capacitance of 338.5 F g−1 in a 6 M KOH electrolyte, and the constructed symmetric supercapacitors deliver high energy densities up to 9.9 Wh kg−1 and 33.87 Wh kg−1 in aqueous and organic electrolytes, respectively. This study provides an effective route for the utilization of wood tar and crab shell waste.

Preparation and Properties of Wood Tar-based Rejuvenated Asphalt.

In order to explore the applicability of the rejuvenated asphalt with wood tar as the main raw material, the orthogonal test was used to determine the optimal ratio of wood tar-based rejuvenator. The physical properties, rheological properties and components of matrix asphalt, aged asphalt, wood tar-based rejuvenated asphalt and commercial RA-102# rejuvenated asphalt were tested and compared. The results show that the optimal ratio of wood tar-based rejuvenator is 15wt% wood tar, 0.3wt% biomass fiber, 5wt% plasticizer, 0.3wt% compatibilizer, and 1wt% stabilizer of the mass of aged asphalt. Wood tar-based rejuvenator can restore the physical properties of the aged asphalt to meet the specification requirements. The synergistic effect of biomass fiber and plasticizer make the wood tar-based rejuvenated asphalt has good resistance to accumulated permanent deformation, but its low-temperature cracking resistance needs to be further improved. During the rejuvenation process of aged asphalt, the colloidal state changes from gel-state to sol-state, characterizing that the viscosity of asphalt decreased and the fluidity increased. Wood tar-based rejuvenator can react with aged asphalt to weaken the vibration strength of carbonyl and sulfoxide groups, so as to realize the recovery of service performance. Wood tar-based rejuvenator has better environmental protection and applicability, which is worthy of further study and promotion.

Mechanisms of lung toxicity induced by biomass burning aerosols

BackgroundCarbonaceous aerosols emitted from indoor and outdoor biomass burning are major risk factors contributing to the global burden of disease. Wood tar aerosols, namely, tar ball particles, compose a substantial fraction of carbonaceous emissions, especially from biomass smoldering. However, their health-related impacts and toxicity are still not well known. This study investigated the toxicity of the water-soluble fraction of pyrolyzed wood tar aerosols in exposed mice and lung epithelial cells.ResultsMice exposed to water-soluble wood tar aerosols showed increased inflammatory and oxidative stress responses. Bronchial epithelial cells exposed to the same water-soluble wood tar aerosols showed increased cell death with apoptotic characteristics. Alterations in oxidative status, including changes in reactive oxygen species (ROS) levels and reductions in the expression of antioxidant genes related to the transcription factor Nrf2, were observed and were confirmed by increased levels of MDA, a lipid peroxidation adduct. Damage to mitochondria was observed as an early event responsible for the aforementioned changes.ConclusionsThe toxicity and health effect-related mechanisms of water-soluble wood tar were investigated for the first time in the context of biomass burning. Wood tar particles may account for major responses such as cell death, oxidative stress, supression of protection mechnaisms and mitochondrial damaged cause by expsoure to biomass burning aerosols.

Deciphering the complexity of a ‘simple’ mesolithic phenomenon: Indicators for construction, use and taphonomy of pit hearths in Kampen (the Netherlands)

Pit hearth features form a common phenomenon in the Mesolithic of North-West Europe, and the Netherlands and adjacent parts of Germany and Belgium in particular. Using soil micromorphology, we investigated the genesis and taphonomy of several pit hearth features, embedded in sandy podzolic soils from Kampen (the Netherlands). This is one of the first studies to investigate one of such pits in its entirety, instead of only the lower, charcoal-rich fill. Our results show that the upper fill of these pits contains considerable amounts of non-charred degraded organic matter. The lower fill typically contains fragments of charcoal and some wood tar, but also black coatings around sand grains, that is interpreted as charred humus from a podzol B-horizon. These coatings indicate that material from the upper horizons of a podzol profile – e.g. in the form of turves - was used to control a fire on the floor of the pit.Fine charred material postdepositionally leached from the pit feature into the underlying deposits, associated with increased formation of limped clay coatings. This indicates that ash-induced alkaline charcoal degradation and associated clay translocation played a role in this process. The Kampen case provides strong evidence that fine charred organic material may contaminate underlying archaeological or sedimentary units.

Olea europaea Subsp. Cuspidata Wood Tar Oil as Anticorrosion for Mild steel in Acidic Media

Olea europaea Subsp. Cuspidata Wood Tar Oil as Anticorrosion for Mild steel in Acidic Media

Sickles of the Funnel Beaker culture in the light of use-wear and residue analysis

The aim of this paper is to present new data on the use of plants and on flint management by Funnel Beaker societies. Studies of usewear and residues on flint tools from the Polwica-Skrzypnik site complex located in SW Poland included microscopic analyses of traces, starch and phytoliths, and adhesives. According to the usewear analysis, most of the tools were used as sickle inserts. The production of sickles was mainly based on good-quality imported flint material, but local groups also supplemented their needs with local flint. The identified phytoliths can be assigned to the grass and sedge families Poaceae and Cyperaceae, respectively, and to the subfamily Panicoideae of Poaceae. Microscopic traces indicate that inserts were re-sharpened during use and recycled by modifying them into other morphological and functional tools, such as hide scrapers. FTIR and GC-MS analyses show that the resinous substance preserved on the surfaces of the flint tools is wood tar, obtained by a process of pyrolysis of the bark of Betulaceae trees.

Chemical characterization of laboratory-generated tar ball particles

Abstract. The chemical properties of laboratory-generated tar ball (Lab-TB) particles produced from dry distillate (wood tars) of three different wood species in the laboratory were investigated by analytical techniques that had never been used before for their characterization. The elemental compositions of laboratory-generated tar balls (Lab-TBs) from three tree species were very similar to one another and to those characteristic of atmospheric tar balls (TBs) collected from the savanna fire during the SAFARI 2000 sampling campaign. The O ∕ C and H ∕ C molar ratios of the generated Lab-TBs were at the upper limit characteristic of soot particles. The Fourier transform infrared spectroscopy (FT-IR) spectra of the generated Lab-TBs were very similar to one another as well and also showed some similarity with those of atmospheric humic-like substances (HULIS). The FT-IR measurements indicated that Lab-TBs have a higher proportion of aromatic structure than HULIS and the oxygen atoms of Lab-TBs are mainly found in hydroxyl and keto functional groups. Whereas Raman activity was detected in the starting materials of the Lab-TBs (wood tars) in the range of 1000–1800 cm−1, the Raman spectra of TBs were dominated by two pronounced bands with intensity maxima near 1580 (G band) and 1350 cm−1 (D band), indicating the presence of sp2-hybridized carbon structures and disorder in them, respectively. In the Py-GC-MS chromatograms of the Lab-TBs mostly aromatic compounds (aromatic hydrocarbons, oxygenated aromatics and heterocyclic aromatics) were identified in accordance with the results of Raman and FT-IR spectroscopy. According to organic carbon ∕ elemental carbon (OC ∕ EC) analysis using EUSAAR_2 thermal protocol, 22 % of the total carbon content of Lab-TBs was identified as EC, contrary to expectations based on the current understanding that negligible if any EC is present in this sub-fraction of the brown carbon family. Our results suggest that spherical atmospheric TBs with high C ∕ O molar ratios are closer to BC in many of their properties than to weakly absorbing HULIS.

Contact sensitivity in patients with venous leg ulcer: A multi-centric Indian study.

Venous leg ulcers are the most common form of non-healing leg ulcers. They are subjected to treatments such as topical medications, dressings, and compression therapies. This can lead to exposure to a number of allergens with subsequent sensitisation and contact dermatitis of the regional skin. This may contribute to the poor ulcer healing. To detect the various contact sensitisers in patients with venous leg ulcers through patch testing, patients from 6 centres across India with venous leg ulcers of longer than 6 weeks duration were enrolled for the study. They were patch tested using a special parch test kit with 27 antigens. A total of 172 patients were included in the study; 82 (48.2%) tested positive for at least 1 antigen. Among them, polyvalent sensitisation was noted in 71% of patients. Wood tar mix (10.4%) and the framycetin (8.7%) were the most common allergens. There is a high frequency of allergic sensitisation to various ingredients of topical therapies used in the venous ulcer management, which may interfere with wound healing. Avoiding them can help obtain a better therapeutic outcome.

Slow Pyrolysis Performance and Energy Balance of Corn Stover in Continuous Pyrolysis-Based Poly-Generation Systems

In order to analyze pyrolysis performance and energy balance of corn stover utilization in continuous pyrolysis, the continuous carbonization tests were carried out on a poly-generation unit of biochar, gas and liquid developed by our research team. Corn stover was naturally dried and crushed to length of 4-7mm, and the heating thermometers are 450, 550, 650℃, the physical and chemical properties, yield rate and influence of technological parameters on them were analyzed. On this basis, the system heat transfer calculation and energy balance analysis were done. Results show that the quality of corn stover char are affected tremendously by pyrolysis temperature and material residence time, the residence time generally should be not less than 30 min. The HHV of pyrolysis gases reach about 20 MJ/Nm3 at pyrolysis temperature of 550 and 650℃. In terms of energy balance, biochar at 47.88% accounts for most of the enthalpy of products, followed by pyrolysis gas (36.17%), and wood tar and light oil, accounting fo...

Characteristics of Wood Tar Produced as Byproduct from Two Types of The Kiln in The Manufacture of Oak Charcoal

This study investigated the characteristics of wood tar, produced as a byproduct during the production of charcoal using oak wood by the modified traditional kiln and mechanical steel kiln. The wood tar was analyzed with a number of techniques, including Py-GC/MS, NMR, MALDI-TOF, FT-IR, TG and DSC. The Py-GC/MS analysis indicated that modified traditional kiln generated a higher hydrocarbon ratio in the wood tar than that of mechanical steel kiln. On the other hand, mechanical steel kiln resulted in a higher proportion of phenolic and aromatic hydrocarbon components than that of modified traditional kiln. Those results were also confirmed by NMR analysis. The MALDI-TOF analysis suggested that the wood tar produced in the mechanical steel kiln had a slightly higher molecular weight than the wood tar produced in the modified traditional kiln. In addition, the FT-IR analysis showed characteristic peak of symmetrical stretching vibration of CH3 from the modified traditional kiln while characteristic peaks of the C-C and C-O stretching vibration were observed from the mechanical steel kiln. Moreover, TG and DSC analysis suggested that the mechanical steel kiln is more thermally stable than that of modified traditional kiln. Those findings clearly showed that the method of making charcoal greatly affects the properties of wood tar.

Outcome of the consultation with Member States and EFSA on the basic substance application for Landes pine tar for use in plant protection as protectant and repellent

EFSA Supporting PublicationsVolume 14, Issue 11 1311E Technical reportOpen Access Outcome of the consultation with Member States and EFSA on the basic substance application for Landes pine tar for use in plant protection as protectant and repellent European Food Safety Authority (EFSA), European Food Safety Authority (EFSA)Search for more papers by this author European Food Safety Authority (EFSA), European Food Safety Authority (EFSA)Search for more papers by this author First published: 20 November 2017 https://doi.org/10.2903/sp.efsa.2017.EN-1311 Requestor: European Commission Question number: EFSA-Q-2017-00611 AboutPDF ToolsExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat References SCCNFP (Scientific Committee on Cosmetics Products and non-Food Products), 2003. Opinion of the Scientific Committee on Cosmetics Products and non-Food Products intended for consumers concerning wood tars and wood tar preparations adopted by the SCCNFP during the 23rd plenary meeting of 18 March 2003. SCCNFP/0646/03, final, 12 pp. European Commission, 2008. Review Report for the active substance blood meal finalised in the Standing Committee on the Food Chain and Animal Health at its meeting on 28 October 2008 in view of the inclusion of blood meal in Annex I of Directive 91/414/EEC. SANCO/2604/08 - rev. 1-3, 9 March 2012. Volume14, Issue11November 20171311E ReferencesRelatedInformation

층상 이중 수화물(Mg-Al-LDH) 첨착 천연제올라이트(Clinoptilolite)를 이용한 가스화 발전설비의 목질계 타르폐수 처리

층상 이중 수화물(Mg-Al-LDH) 첨착 천연제올라이트(Clinoptilolite)를 이용한 가스화 발전설비의 목질계 타르폐수 처리

Preparation and Mechanical Properties of Melt-spun Carbon Fibers from Wood Tar and Wood Tar/Kraft Lignin Blends

Preparation and Mechanical Properties of Melt-spun Carbon Fibers from Wood Tar and Wood Tar/Kraft Lignin Blends

Organic substances from Egyptian jars of the Early Dynastic period (3100–2700 BCE): Mode of preparation, alteration processes and botanical (re)assessment of “cedrium”

Organic substances from three jars found at Abydos in the tombs of Kings from the two first Egyptian dynasties (3100–2700BCE) were investigated using gas chromatography–mass spectrometry in order to assess their biological origin, use and mode of preparation. The organic material was found to correspond to essential oils from conifers severely altered/oxidized. A predominant contribution from Cedrus libani was determined from the identification of sesquiterpenoid derivatives of the himachalene series which constitute new molecular tools for the identification of ancient oils made from real cedars. The presence of cuparene-related terpenoids suggests an additional contribution of members from the Cupressaceae family (junipers, cypresses). The genuine substances were most likely prepared in the Levant since neither C. libani nor junipers or cypresses are native from Egypt. Despite obvious analogies with “cedrium” used for embalming during later periods, their use as ingredients for embalming remains uncertain because true embalming only began in Egypt after 2500BCE. Instead, it is proposed that these substances have been used as cosmetics, medicinal substances or for cultual purposes. The predominance of low molecular weight sesquiterpenoids and the absence of typical markers for wood tars indicate that the substances have possibly been prepared by steam-distillation of odoriferous plant material rather than by pyrolysis. Our study gives clues to the controversy concerning the composition of “cedrium”, indicating that it most likely originates from mixed true cedar and junipers or cypresses, and not exclusively from real cedar vs. juniper oil.

3-3-4 木タールの接触熱分解によるガス燃料と機能性炭素の併産(3-3 ガス化1・熱分解3,Session 3 バイオマス等,研究発表)

3-3-4 木タールの接触熱分解によるガス燃料と機能性炭素の併産(3-3 ガス化1・熱分解3,Session 3 バイオマス等,研究発表)

Identification of alkyl guaiacyl dehydroabietates as novel markers of wood tar from Pinaceae in archaeological samples

Resinous material from conifers from the Pinaceae family is frequently found in an archaeological context. The material was used, notably, as waterproofing agent, as adhesive or for the caulking of boats. Two main types of material can be distinguished: resin, the exudate of conifer trees, and wood tar obtained by dry distillation of wood. Molecular investigation of such material aims, notably, at developing new molecular tools for the determination of the biological and geographical origin or of the manufacturing techniques, and for the discrimination between resin and wood tar. In this context, we report the identification by synthesis of alkyl guaiacyl dehydroabietates, which occur in a series of recent and archaeological conifer wood tar samples from shipwrecks and Gallo-Roman tar preparation sites. They most likely result from the reaction of dehydroabietic acid and alkyl guaiacols, the latter being typical wood pyrolysis products formed during the preparation of wood tar. Alkyl guaiacyl dehydroabietates are therefore proposed to be specific molecular markers for conifer wood tar, allowing a clear molecular distinction between this material and resin to be made. They are also more resistant to the alteration undergone by archaeological samples than other compounds previously proposed as markers of conifer wood tar such as anhydrosugars or alkyl guaiacols.

Wood-Derived Tar as a Carbon Binder Precursor for Carbon and Graphite Technology

In addition to the many benefits of coal tar pitch, these materials are known to contain polycyclic aromatic hydrocarbons. For this reason, studies are being developed to elaborate new, ecologically friendly, alternative binders for carbon–graphite technology. This article presents the results of wood tar recovered during thermal degradation of selected types of woods as alternative binders in the manufacture of carbon materials. Two kinds of wood tars obtained from different raw materials were analyzed. Sawdust thermal conversion makes it possible to obtain carbon binders with a lower coking value and quinoline-insoluble matters in comparison to coal tar pitch. These binders produce significantly reduced emissions of polycyclic aromatic hydrocarbons in carbon–graphite technology. Carbon samples manufactured using wood-derived binders with carbon fillers showed similar density and mechanical compression strength values compared to those based on conventional coal tar pitch binders.

Light absorption properties of laboratory-generated tar ball particles

Abstract. Tar balls (TBs) are a specific particle type that is abundant in the global troposphere, in particular in biomass smoke plumes. These particles belong to the family of atmospheric brown carbon (BrC), which can absorb light in the visible range of the solar spectrum. Albeit TBs are typically present as individual particles in biomass smoke plumes, their absorption properties have been only indirectly inferred from field observations or calculations based on their electron energy-loss spectra. This is because in biomass smoke TBs coexist with various other particle types (e.g., organic particles with inorganic inclusions and soot, the latter emitted mainly during flaming conditions) from which they cannot be physically separated; thus, a direct experimental determination of their absorption properties is not feasible. Very recently we have demonstrated that TBs can be generated in the laboratory from droplets of wood tar that resemble atmospheric TBs in all of their observed properties. As a follow-up study, we have installed on-line instruments to our laboratory set-up, which generate pure TB particles to measure the absorption and scattering, as well as the size distribution of the particles. In addition, samples were collected for transmission electron microscopy (TEM) and total carbon (TC) analysis. The effects of experimental parameters were also studied. The mass absorption coefficients of the laboratory-generated TBs were found to be in the range of 0.8–3.0 m2 g−1 at 550 nm, with absorption Ångström exponents (AAE) between 2.7 and 3.4 (average 2.9) in the wavelength range 467–652 nm. The refractive index of TBs as derived from Mie calculations was about 1.84 − 0.21i at 550 nm. In the brown carbon continuum, these values fall closer to those of soot than to other light-absorbing species such as humic-like substances (HULIS). Considering the abundance of TBs in biomass smoke and the global magnitude of biomass burning emissions, these findings may have substantial influence on the understanding of global radiative energy fluxes.

Semi-empirical model for estimating molar fraction of syngas produced by thermal cracking of wood tar

To optimize the efficiency of the wood gasification, tar which limits the use of syngas in thermal engines must be reduced. The quantity, quality and composition of syngas produced after thermal cracking of tar were analysed, and mathematical equations formulated based on Newton’s bivariate polynomial interpolation were used to estimate the molar fraction of the gases. The conceptual analysis of the problem was based on experimental data of temperature and residence time, and the semi-empirical model was simulated using Matlab to predict the composition of the syngas and the tar content in the gas mixture. The thermal cracking of tar increased the amount of syngas produced; in particular, the molar fraction of carbon monoxide and hydrogen. The gasification energy efficiency also improved with temperature and residence time, as the quantity of tar was reduced during cracking. The model was validated by comparing the experimental and numerical data. Keywords: Syngas, Gasification, Pyrolysis, Residence time, Thermal cracking of tar, Semi-empirical model

Properties and Combustion Characteristics of Molded Solid Fuel Particles Prepared by Pyrolytic Gasification or Sawdust Carbonized Carbon

Pyrolytic gasified charcoal (PGC) and tar are the solid and liquid products, respectively, yielded from biomass gasification technology. In this paper, PGC was molded with adhesives to prepare molded solid fuel (MSF). Tar and PGC were obtained from the pyrolytic gasification of wood chips and sawdust from pine and cedarwood. PGC was molded with phenol resin prepared by wood tar to prepare MSF (MSF-MP). Meanwhile, there were two other methods used to prepare MSF. PGC molded with common phenol resin was one method (MSF-P). PGC was molded with starch adhesive to prepare MSF-S. Wood powder carbonized carbon (WPCC) obtained from the marketplace was employed as a trial sample. The properties and combustion characteristics of MSFs and WPCC were studied. It was found that the shatter strength of these MSFs were more than 95%. MSFs had higher activation energy and comprehensive combustion index compared to WPCC. MSF-MP yielded the following data: shatter strength: 95.86%, lower heating value (LHV): 25.89 MJ∙kg-1, ignition: 325 °C, comprehensive combustion index: 1.73×10-10, and activation energy: 61.38 kJ∙mol-1. The LHV and activation energy of MSF-MP were superior to those of other MSFs. Therefore, MSF-MP has a market potential for use as barbecue charcoal in restaurant or family gatherings. The preparation of MSF-MP is a prospective method for the utilization of PGC and wood tar.