Pyrolysis bio-oil from biomass is a promising intermediate for producing transportation fuels and platform chemicals. However, its instability, often called aging, has been identified as critical hurdle that prevents being commercialized. The objective of this research to explore the aging mechanism by an accelerated test fractionated produced loblolly pine. When water soluble (WS), ether insoluble (EIS), pyrolytic lignin (PL) fractions were aged separately, increased molecular weight (Mw)...

The objective of this paper is to investigate the biomass torrefaction effect on bio-oil stability by comparing physicochemical and compositional properties aged bio-oils. Two aging methods, accelerated (held at 80 °C for 24 h) long-term natural (12-month storage 25 °C), were employed produce bio-oils such comparison. results indicate that made from heat-treated wood had similar behavior in terms increase water content, acid molecular weight, viscosity. rate, however, was found be different...

Biochar from lignocellulosic biomass is emerging as a sustainable material with versatile applications, but its detailed properties are poorly understood because of structural complexity. We propose biochar development model based on experimental results including composition analysis, surface area and pore X-ray diffraction electron microscopy imaging, energy loss spectroscopy. Loblolly pine derived biochars were produced at different carbonization temperatures between 300 to 1000 °C. Fixed...

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTDetermination of BTEX Compounds in Water by Solid-Phase Microextraction and Raman SpectroscopyBrian L. Wittkamp David C. TilottaCite this: Anal. Chem. 1995, 67, 3, 600–605Publication Date (Print):February 1, 1995Publication History Published online1 May 2002Published inissue 1 February 1995https://pubs.acs.org/doi/10.1021/ac00099a018https://doi.org/10.1021/ac00099a018research-articleACS PublicationsRequest reuse permissionsArticle...

A stationary Hadamard encodement mask has been designed from a liquid crystal display. This mask, when properly installed and positioned in dispersive instrument, allows the selected encoded spectral elements to be focused on single detector. Discussion of advantages derived by this technique is presented. Several emission spectra visible near-infrared region demonstrate usefulness transform technique. novel spectrometer can provide no-moving-parts spectroscopy for future applications.

The successful application of LC-SLM Hadamard transform spectrometry as a simultaneous multiwavelength detection system to Raman spectroscopy is presented. Multiplexed data are obtained with the use an Ar + laser lasing at 514.5 nm and room-temperature silicon photodiode. A conventional 90° scattering geometry employed for measurements. It demonstrated that spectrometer possesses capability performing spectral subtraction ability obtain depolarization ratios bands, can function selectively...

The existence of radicals in pyrolysis oil generated from loblolly pine three different reactor systems was verified with electron paramagnetic resonance (EPR) spectroscopy.

A simple method is described for determining aromatic compounds (i.e., benzene, toluene, ethylbenzene, etc.) in water that combines solid phase microextraction (SPME) and ultraviolet (UV) absorption spectroscopy. The extraction medium consists of a small "chip" poly(dimethylsiloxane) (total volume ∼80 μL) immersed sample contaminated with an compound. Equilibrium first allowed to establish between the analyte medium, concentration compound then determined directly sorbent chip by UV...

A simple method is described combining solid phase microextraction (SPME) and infrared (IR) spectroscopy for determining volatile organic compounds (VOCs) in water. The consists of a small square Parafilm (130 μm thick) that used to selectively extract the VOCs from Infrared transmission detect extracted directly Parafilm. Ten (e.g., benzene, chlorobenzene, toluene, chloroform, p-chlorotoluene) are chosen evaluate SPME-IR procedure. Preliminary experiments show detection limits 66 ppb−1.3...

A method is described for the determination of aromatic contaminants in water samples that combines solid-phase microextraction and ultraviolet evanescent wave absorption (UV-EWA) spectroscopy. In this method, compounds are partitioned from a 10 mL sample into polymer cladding cm length UV-transmitting fiber. The aromatics then detected directly by EWA time required four BTEX to reach concentration equilibrium between aqueous phase ranges 12 80 min, although we show quantitative...

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTSimple Fiber-Optic Interface for Online Supercritical Fluid Extraction Fourier Transform Infrared SpectrometryDaniel L. Heglund, David C. Tilotta, Steven B. Hawthorne, and J. MillerCite this: Anal. Chem. 1994, 66, 20, 3543–3551Publication Date (Print):October 15, 1994Publication History Published online1 May 2002Published inissue 15 October 1994https://pubs.acs.org/doi/10.1021/ac00092a041https://doi.org/10.1021/ac00092a041research-articleACS...

The effect of a uniform bistable optical transmission defect in the encoding mask on multiplex efficiency is investigated for solid-state Hadamard transform spectrometry with thermal detection. It demonstrated that masks which possess nonideal properties, i.e., defects, need not impare capability provided sufficient number resolution elements are multiplexed. Application to SNR general algorithm calculation average mean square error estimate spectrum shows reasonable improvements can be...

Chemical esterification of wood biopolymers using acetic acid is a green method to sustain and improve the physical properties native tropical hardwoods in part by drastically reducing surface energy.

The thermal fragmentation of organic compounds in a hydrogen/air flame is studied via Fourier transform infrared emission (FT-FIRE) spectroscopy. In this preliminary survey more than 75 compounds, it shown that compound and element-specific bands are produced when containing C, H, Cl, F, S, Si combusted the flame. Correlations these with possible combustion products presented.

Low-temperature pyrolysis offers a feasible option for wood waste management and the recovery of variety useful chemicals. In this study, effect chromated copper arsenate (CCA) preservatives on yield composition various products was investigated over temperature range 275−350 °C. For preliminary work, we examined feasibility using gas chromatography coupled with either flame ionization detection or mass spectroscopic novel 31P nuclear magnetic resonance (NMR) method. Both methods worked...

The use of supercritical argon is described for the extraction petroleum hydrocarbons from soil samples. Argon an attractive solvent because it inexpensive and inert. Additionally, has a clear spectral window in infrared region which makes useful on-line (i.e., directly coupled) experiments. Spiking studies conducted with gasoline, no. 1 fuel oil, 5 oil on sand, loam, clay show that component recovery rates fluid (SFE) generally increase increasing pressure and/or temperature. highest (and...

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTDetermination of chloride and available chlorine in aqueous samples by flame infrared emissionS. W. Kubala, D. C. Tilotta, M. A. Busch, K. BuschCite this: Anal. Chem. 1989, 61, 24, 2785–2791Publication Date (Print):December 15, 1989Publication History Published online1 May 2002Published inissue 15 December 1989https://doi.org/10.1021/ac00199a020RIGHTS & PERMISSIONSArticle Views325Altmetric-Citations22LEARN ABOUT THESE METRICSArticle Views are the...

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTSynthesis and magnetic resonance spectroscopy of novel phenolato-bridged manganese(III) iron(III)-manganese(III) porphyrin complexesGregory M. Godziela, David Tilotta, Harold GoffCite this: Inorg. Chem. 1986, 25, 13, 2142–2146Publication Date (Print):June 1, 1986Publication History Published online1 May 2002Published inissue 1 June 1986https://pubs.acs.org/doi/10.1021/ic00233a009https://doi.org/10.1021/ic00233a009research-articleACS...

Abstract Acetylation of wood is an age‐old chemical platform known to improve its and physical properties in direct correlation with the degree acetylation. However, as yet, no systematic study has been undertaken probe selectivity acetylation wood. A fundamental understanding molecular basis for constituent biopolymers, viz., holocellulose, lignin tropical hardwood, emerging building material, therefore undertaken. Wood samples are treated acetic anhydride at 120 °C over a wide range time...

A new method is described for determining nitroaromatic compounds in water that combines solid-phase microextraction (SPME) and infrared (IR) spectroscopy. In this method, the are extracted from a 250-mL volume of into small square (3.2 cm × 3.2 61.2 μm thick) silicone polycarbonate copolymer film (MEM-213). Five compounds, including 2,4,6-trinitrotoluene (TNT), were chosen to evaluate SPME/IR procedure. Quantitation limits five test range 50 μg/L TNT 400 nitrobenzene. Precision values,...