The self-bonding of air-dry bagasse and bagasse pith exhibited during hot-pressing in a closely fitting mold is studied under varying conditions. It is shown that the ability of the particles to pack up closely is most important to self-bonding. The pith fraction which causes great trouble in paper and fiberboaid making gives a highly densified, plastic-like product superior to t hose from whole or depithed bagasse. This is attributed to the high lumen to cell wall ratio which favours the formation of interparticle bonds. Bending strength up to 130 N/mm 1 and water absorption äs low äs 10% are obtained at 25.5 MPa molding pressure and 175 °C. Increasing the initial moisture content of pith from 7 to 14 percent results in deterioration of both strength and water resistance while the contrary applies to depithed bagasse. Eventually, the mechanism of self-bonding is discussed. Bindemittelfreier lignocellulosischer Preßstoffaus Bagasse und Mechanismus der EigenverklebungZusammenfassung Das Eigenbindevermögen von lufttrockener Bagasse und Bagassemark, das während der Hitze-Druckbehandlung in einer dicht schließenden Preßform sich entwickelt, wird unter variierten Bedingungen untersucht. Es zeigt sich, daß die Fähigkeit der Partikel, in engen Kontakt miteinander zu kommen, äußerst wichtig für die Eigenverklebung ist. Die Markfraktion, die große Schwierigkeiten bei der Papierund Faserplattenherstellung macht, ergibt ein hochverdichtetes, kunststoffähnliches Produkt, das denen aus nicht entmarkter und entmarkter Bagasse überlegen ist. Man kann dies auf das hohe Lumen: Zellwand-Verhältnis zurückfuhren, das die Bildung von Bindungen zwischen den Partikeln begünstigt. Biegefestigkeiten bis zu 130 N/mm 2 und eine Wasseraufnahme von nicht mehr als 10% werden bei 25,5 MPa Preßdruck und 175 °C erhalten. Erhöht man die Ausgangsfeuchte der Markfraktion von 7% auf 14%, so verschlechtern sich sowohl Festigkeit als auch Wasseraufnahme und Dickenquellung. Das genaue Gegenteil trifft für entmaikte Bagasse zu. Abschließend wird der Mechanismus der Eigenverklebung diskutiert.About thirty years ago, Runkel and Jost (1948) developed a process for making highly densified molded products

Biomass pyrolysis is a promising renewable sustainable source of fuels and petrochemical substitutes. It may help in compensating the progressive consumption of fossil-fuel reserves. The present article outlines biomass pyrolysis. Various types of biomass used for pyrolysis are encompassed, e.g., wood, agricultural residues, sewage. Categories of pyrolysis are outlined, e.g., flash, fast, and slow. Emphasis is laid on current and future trends in biomass pyrolysis, e.g., microwave pyrolysis, solar pyrolysis, plasma pyrolysis, hydrogen production via biomass pyrolysis, co-pyrolysis of biomass with synthetic polymers and sewage, selective preparation of high-valued chemicals, pyrolysis of exotic biomass (coffee grounds and cotton shells), comparison between algal and terrestrial biomass pyrolysis. Specific future prospects are investigated, e.g., preparation of supercapacitor biochar materials by one-pot one-step pyrolysis of biomass with other ingredients, and fabricating metallic catalysts embedded on biochar for removal of environmental contaminants. The authors predict that combining solar pyrolysis with hydrogen production would be the ecofriendliest and most energetically feasible process in the future. Since hydrogen is an ideal clean fuel, this process may share in limiting climate changes due to CO 2 emissions.

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Self-bonding of air dry undebarked cotton stalks during hot pressing in a closely fitting mold was studied. Advanced board like green nanocomposites from ground undebarked cotton stalks were introduced, for the first time, in the present work. The dry forming process was adopted. Moderate molding pressure and temperature were selected and applied in a tight die. Thus saving water, energy, and avoiding the use of any binders; to achieve an environment friendly green product. Green Nanocomposites having densities in the range 1.27-1.29g/c.c. as well as 1.03-1.06 g/c.c. were prepared. It was found that particle size, and cell wall morphological structure play a great role in se1f bonding.Properties of composites prepared from the fine fraction of cotton stalks were superior to those prepared from cotton stalks coarse fraction at same conditions. This is attributedamong other things -to the dominance of pith (parenchyma cells) in the fine fraction. Such cells possess a high lumen to cell wall ratio, which renders them more deformable under pressure leading to more intercellular or interparticle bonding. Advanced Binderless Green Nanocomposites having bending strength as high as 637 Kg/cm 2 and water absorption as low as 12.1% were obtained from the ground undebarked cotton stalks. The results show clearly that the advanced green nanocomposite obtained by dry forming process, without addition of any binders, is superior to hardboard obtained from cotton stalks by the conventional wet web formation process. The mechanism of self-bonding was discussed.

This work introduces, for the first time worldwide, an advanced nanocomposite involving two additives-a nanoadditive and a conventional additive-within a matrix of natural cellulose fibers. The first additive (the nanoadditive) is sucrose, which incorporates the nanoporous structure of the cell walls of cellulose fibers. The second additive (the conventional additive) is kaolin, the famous paper filler. Kaolin is enmeshed between the adjacent cellulose fibers. This advanced paper nanocomposite was prepared by simple techniques. The present work shows, for the first time, that sucrose can overcome the ultimate fate of deterioration in strength of paper, due to addition of inorganic fillers such as kaolin. This deterioration was counteracted by incorporating cellulose fibers with sucrose, which leads to incorporation beating of the fibers, and thus increases the strength of the produced paper nanocomposites. In addition, sucrose was proven-for the first timeto act as retention aid for inorganic fillers such as kaolin. We called this phenomenon incorporation retention to differentiate it from the conventional types of retention of inorganic fillers. Recent studies, by the authors and others, have shown that incorporating cellulose fibers, with sucrose, leads to paper nanocomposites of enhanced strength (breaking length). Also, sucrose is privileged by its small size (0.8nm), substantial hydrogen bonding capacity, low cost, and p 3 of 21 tp abundance. Therefore, sucrose was chosen as a nanoadditive in this work. The present study shows that the nanoadditive sucrose may find its use as a new retention aid and strength promoter in papermaking. p 4 of 21 tp