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Fossil fuels are the major energy source used in the world and will continue to dominate in the future. For the coal-dependent countries, the key to the emission reduction of CO2 will be the capture of CO2 in coal-fired power plants. Currently available CO2 sorbents are reviewed in this paper. Based on the principles of various separation technologies, absorption and adsorption are discussed accordingly. In terms of the application temperature, absorption materials are categorized into high-temperature absorbent and low-temperature absorbent and their latest progress are included. For the adsorption, different materials such as activated carbon, zeolite and MOFs and etc. are discussed thoroughly. At the end, the future trend of CO2 separation is proposed. It is suggested that since any single method cannot meet the requirements of coal-fired power plants, feasible approach for CO2 separation will be to combine the advantages of all the available methods, for example, adsorbents impregnated with amines, porous polymer impregnated with organic solvents and new structured adsorbents such as ionic liquids and metal organic frames. [ABSTRACT FROM AUTHOR]

The ability of successive ionic layer deposition (SILD) technology to synthesize gold clusters on the surface of tin(IV) oxide and indium(III) oxide films is discussed. It was shown that during the process, concentration of active sites that are capable of absorbing gold ions, and the size of the gold particles thus formed, may be controlled by both concentration of the solutions used and the number of SILD cycles. Thus, SILD methodology, employing separate and multiple stages of adsorption and reduction of adsorbed species, has considerable potential for customizing the properties of the deposited metal nanoparticles. In particular, it is shown that during the deposition of gold nanoparticles on the surface of tin(IV) oxide and indium(III) oxide films by SILD methodology, conditions can be realized under which the size of gold nanoclusters may be controllably varied between 1-3 nm and 50 nm. A model is proposed for the formation of gold clusters during the SILD process. [ABSTRACT FROM AUTHOR]

The combined bound water and water vapour diffusion of wood is of great interest in the field of building physics. Due to swelling stresses, the steady-state-determined diffusion coefficient clearly differs from the unsteady-state-determined diffusion coefficient. In this study, both diffusion coefficients and the water vapour resistance factor of Norway spruce ( Picea abies [L.] Karst.) and European beech ( Fagus sylvatica L.) were investigated for the principal anatomical directions (radial, tangential and longitudinal) and in 15° steps between these directions. The values were determined with the cup method as the basic principle. The unsteady-state-determined diffusion coefficient is, independent of the direction, about half that of the steady-state-determined diffusion coefficient. Both diffusion coefficients are about two to three times higher for spruce than for beech. They are up to 12 times higher in the longitudinal direction than perpendicular to the grain for spruce, and up to 15 times higher for beech. With increasing moisture content, the diffusion coefficients exponentially increase. The water vapour resistance factor shows converse values to the diffusion coefficients. [ABSTRACT FROM AUTHOR]

No abstract available [ABSTRACT FROM AUTHOR]

AbstractSamples of wood pellets were adjusted into six water content classes from 0% to 12%. The water content in single pellets varied between 0.1% and 14.2%. Three equations were constructed to estimate the differential heat of sorption (-ΔH) values from (1) fractal-geometry, (2) isosteric, and (3) calorimetric data. The ranges in calculated -ΔHof single pellets were (1) 133–1475, (2) 315–881, and (3) 195–1188 J g-1water, respectively, across the studied moisture content range. Partial least squares regression was used to model near-infrared (NIR) spectra from single pellets and to predict -ΔHvalues and water content. The explained variation in test sets for the different models ranged from 97.1% to 99.9%. The shifts in peak absorbance for two water bands indicated that frequency in overtone vibration of O-H stretching and bending decreased, when water content was raised. Simulations of mixes between pellets of differential heat values showed that released heat was up to 0.03% of the gross calorific value of wood pellets. This heat may be a major contributor to initial temperature increases in pellet stacks during storage. The results indicate that on-line NIR based predictions of differential heat in wood pellets is possible to apply in the pellet industry. [ABSTRACT FROM AUTHOR]

The adsorption of copper, [as Cu(II)], monoethanolamine (MEA) and didecyldimethyl ammonium chloride (DDAC) components of CuMEA and alkaline copper quaternary (ACQ) solutions impregnated into wood was followed by measuring the changes in solution concentrations in the wood over time. The rate and extent of copper and MEA adsorption were highly dependent on the solution strength and the conditioning temperature. Both copper and MEA were adsorbed by the wood structure with a rapid initial reaction, with higher relative amounts sorbed from lower concentration solutions. This was followed by a slower adsorption that still had not equilibrated after 7 weeks at 22°C. Generally, the adsorption pattern was similar for copper and MEA, suggesting that they were adsorbed as a copper MEA complex, with an MEA/copper molar ratio close to the theoretical maximum of 4. At a higher conditioning temperature of 50°C the reaction time was greatly reduced, with the adsorption after 1 week higher than after 7 weeks at 22°C, suggesting faster and more complete reaction at higher temperatures. DDAC was adsorbed more quickly and to a higher degree than Cu(II) for all treatment solutions and should be preferentially removed from such solutions, especially if empty-cell treatments are used. There appeared to be higher Cu adsorption from the higher concentration solutions of CuMEA than from corresponding ACQ solutions, likely due to DDAC competition with copper for the same reaction sites. [ABSTRACT FROM AUTHOR]

Presents a study on the equilibrium moisture content (EMC) of semi-defatted pumpkin seed flour. Temperature used to determine the EMC of the flour; Equations used to verify the description of the sorption isotherms; Experimental data obtained for adsorption and desorption.

The methods so far applied to determine the bound water diffusion coefficient in wood do not provide credible results on this coefficient as well as on the boundary condition. An alternative approach based on the concept of solving the inverse transfer problems was recently applied. Two European species were investigated in the present study. A series of sorption experiments was performed and followed by the numerical identification of the coefficients. Several case studies were carried out for the constant and bound water content dependent diffusion coefficients. The obtained results were validated by comparison to a set of experimental data. [ABSTRACT FROM AUTHOR]