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Activated carbons were produced from several solid wastes, namely, waste PET, waste tires, refuse derived fuel and wastes generated during lactic acid fermentation from garbage. Activated carbons having various pore size distributions were obtained by the conventional steam-activation method and via the pre-treatment method (i.e., mixture of raw materials with a metal salt, carbonization and acid treatment prior to steam-activation) that was proposed by the authors. The liquid-phase adsorption characteristics of organic compounds from aqueous solution on the activated carbons were determined to confirm the applicability of these carbons, where phenol and a reactive dye, Black5, were employed as representative adsorbates. The hydrophobic surface of the carbons prepared was also confirmed by water vapor adsorption. The characteristics of a typical commercial activated carbon were also measured and compared. It was found that the activated carbons with plentiful mesopores prepared from PET and waste tires had quite high adsorption capacity for large molecules. Therefore they are useful for wastewater treatment, especially, for removal of bulky adsorbates. [Copyright &y& Elsevier]

The solids motion in a gas–solid fluidized bed was investigated via discrete particle simulation. The motion of individual particles in a uniform particle system and a binary particle system was monitored by the solution of the Newton''s second law of motion. The force acting on each particle consists of the contact force between particles and the force exerted by the surrounding fluid. The contact force is modeled by using the analogy of spring, dash-pot and friction slider. The flow field of gas was predicted by the Navier–Stokes equation. The solids distribution is non-uniform in the bed, which is very diluted near the center but high near the wall. It was also found that there is a single solids circulation cell in the fluidized bed with ascending at the center and descending near the wall. This finding agrees with the experimental results obtained by Moslemian. The effects of the operating conditions, such as superficial gas velocity, particle size, and column size on the solids movement, were investigated. In the fluidized bed containing uniform particles better solids mixing was found in the larger bed containing smaller size particles and operated at higher superficial gas velocity. In the system containing binary particles, it was shown that under suitable conditions the particles in a fluidized bed could be made mixable or non-mixable depending on the ratios of particle sizes and densities. Better mixing of binary particles was found in the system containing particles with less different densities and closer sizes. These results were found to follow the mixing and segregation criteria obtained experimentally by Tanaka et al. [Copyright &y& Elsevier]

[Display omitted] • The MS-Ni improved syngas yield by 70 %, reduced tar by 10 folds, compared to the Ar. • The MS-Ni improved syngas yield by 15 %, reduced tar by 5 folds, compared to the MS. • The MS-Ni increased heating rate by 1.3 times, compared to the pyrolysis in the MS. • The MS-Ni increased heating rate by 7 times, compared to the pyrolysis in the Ar. The syngas production from cellulose pyrolysis was studied in carbonate salts combined with nickel supported on alumina catalyst (MS-Ni) in a preheated reactor. Tar content was greatly reduced by 10 folds when compared to that of the pyrolysis in argon gas (Ar). Molten salt resulted in the reduction of tar and CO 2 formation due to the rapid heating of 141 °C/s alter the pyrolysis pathway to produce more syngas products. Further tar elimination was promoted with the presence of nickel supported on alumina catalyst in the salt. Tar was reduced by 5 folds when compared to that the pyrolysis in sole molten salt (MS). Tar from pyrolysis in MS-Ni was about 1 wt%. In addition, CH 4 could be reformed with CO 2 into additional syngas over the Ni/Al 2 O 3 catalyst. As a result, the pyrolysis in the combined salt and catalyst exhibited high syngas yield at 824 mL/g cellulose. Moreover, alumina particles enhanced the heat transfer in the molten salt, resulting in the highest heating rate of 181 °C/s obtained in MS-Ni medium. However, the catalyst deactivation was a serious issue in combining molten salt with Ni/Al 2 O 3 catalyst. The high corrosiveness would damage the alumina support, while the Ni active metal would be leached from the catalyst particles, resulting in the catalyst deactivation. [ABSTRACT FROM AUTHOR]

Research and development of nanocellulose and nanocellulose-reinforced composite materials have garnered substantial interest in recent years. This is greatly attributed to its unique functionalities and properties, such as being renewable, sustainable, possessing high mechanical strengths, having low weight and cost. This review aims to highlight recent developments in incorporating nanocellulose into rubber matrices as a reinforcing filler material. It encompasses an introduction to natural and synthetic rubbers as a commodity at large and conventional fillers used today in rubber processing, such as carbon black and silica. Subsequently, different types of nanocellulose would be addressed, including its common sources, dimensions, and mechanical properties, followed by recent isolation techniques of nanocellulose from its resource and application in rubber reinforcement. The review also gathers recent studies and qualitative findings on the incorporation of a myriad of nanocellulose variants into various types of rubber matrices with the main goal of enhancing its mechanical integrity and potentially phasing out conventional rubber fillers. The mechanism of reinforcement and mechanical behaviors of these nanocomposites are highlighted. This article concludes with potential industrial applications of nanocellulose-reinforced rubber composites and the way forward with this technology. [ABSTRACT FROM AUTHOR]