ABSTRACT
We report for the first time the evaluation of oils from the tropical forest tree, Allanblackia, shea butter and palm kernel oil as a potential phase change material for thermal energy storage based upon its thermo-physical and chemical properties. Differential Scanning Calorimetry showed that all the oils were polymorphic and hence exhibited multiple melting/freezing profile over a wide range. For both melting and freezing cycles, Allanblackia oil showed high latent heat of energy (80.53â¯J/g) with the highest melting point profile (34.74⯰C) of all the oils. Thermo-gravimetric analysis showed that all the oil samples were thermally stable and did not degrade within the temperature of interest even though Allanblackia oil showed an increase in weight around 37⯰C indicating oxidative instability. Chemical stability was confirmed by FTIR spectra. Of all the oils studied, Allanblackia exhibited a potential for use as a PCM for thermal energy storage if purified to improve oxidative stability.
ABSTRACT
This paper is the first of a two series papers on the use of near infrared (NIR) coupled with multivariate data analysis (MVDA) as a process analytical technology (PAT) tool for the rapid characterization of physical and chemical properties of two common West Virginian hardwood species, northern red oak (Quercus rubra) and yellow-poplar (Liriodendron tulipifera L.). These two wood species are potential feed stock for the bio-refinery industry. In Part 1, we report our results on yellow-poplar. The results of this study demonstrated that some preprocessing operations on the NIR spectra (first derivative) greatly improved all the prediction models developed in the study. Predictive PLS1 models developed using selective spectra regions, 1300-1800 nm and the full NIR region (800-2400 nm), were similar. The selective spectra region, 1300-1800 nm, included the first and second overtone of the NIR spectrum (1300-1800 nm). Measured and predicted physical and chemical properties of yellow-poplar yielded moderate to high correlation (R2).
Subject(s)
Biomass , Liriodendron/growth & development , Spectroscopy, Near-Infrared/methods , Calibration , Least-Squares Analysis , Lignin/metabolism , Models, Biological , Multivariate AnalysisABSTRACT
High-performance liquid chromatography (HPLC) coupled to an evaporative light scattering detector was used to quantitatively determine glucose and cellobiose in hydrolyzates from the production of cellulose nanofillers from modified lignocellulosic materials. Prevail Carbohydrate ES 5 micron column proved more suitable for achieving the chromatographic separation of the model pulp hydrolyzate into its constituent sugars than the YMC-Pack Polyamine column. Linear calibration curves for the various sugars in the mixtures were developed. Glucose and cellobiose were clearly detectable in pulp hydrolyzates obtained from enzyme-mediated hydrolysis of recycled pulp, pine and hardwood dissolving pulps. Finally, the amount of glucose in the pulp hydrolyzates was generally higher than cellobiose.
Subject(s)
Carbohydrates/analysis , Cellulase/metabolism , Chromatography, High Pressure Liquid/methods , Scattering, Radiation , Hydrolysis , Light , Time Factors , VolatilizationABSTRACT
This study examined the production of cellulose nanocrystals from microcrystalline wood cellulose, Avicel and recycled pulp of wood pulp using sono-chemical-assisted hydrolysis. Two hydrolysis systems: deionized water and maleic acid were evaluated. In deionized water, Avicel produced cellulose nanocrystals with average diameter of 21+/-5 nm (minimum 15 nm and maximum 32 nm). Cellulose nanocrystals from recycled pulp were not distinctively spherical and had an average diameter of 23+/-4 nm (minimum 14 nm and maximum 32 nm). Maleic acid (50 mM) sono-chemical assisted hydrolysis of Avicel at 15 degrees C and 90% power output for 9 min produced cellulose nanocrystals which were cylindrical in shape and were of dimensions, length 65+/-19 nm and width 15 nm.