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.

To evaluate the utilization of reed in environmental friendly high-density particleboard, modified wheat gluten was used with urea-formaldehyde as a binder in different ratios, applying the optimum conditions obtained on using UF resin alone. The scanning electron microscopy of the reed fibers showed that the fibers are cylindrical in shape, which helps in enhancing the adhesion between the binder and the inner and outer surfaces of the fibers. The dependence of the mechanical properties (modulus of rupture, modulus of elasticity and the internal bond) and the physical properties (water absorption and thickness swelling) on the urea-formaldehyde/modified gluten ratios was studied. Addition of 1% and 2% boric acid as a fungicide to the binder mixture resulted in no significant change in the mechanical properties and slight improvement in the physical properties of the produced particleboard. Thermogravimetric analyses of selected samples were done to study the thermal stability of the particleboard bonded with the modified binder with and without boric acid.

It is shown for the first time world wide, in the present work, that sucrose can be easily placed by simple techniques within the micropores or nanostructure of the mercerized non-dried cotton linters fibers to create a low cost cellulose substitute. Such sucrose-containing nanocomposites find their suitable uses as specialty absorbent paper. Relative to the sucrose-free paper, the sucrose-containing counterparts exhibit greater breaking length and remarkably high water uptake (W.R.V.) up to sucrose-content 8-15 % w/w. Mercerization of cotton linters, before incorporating them with sucrose, greatly enhanced the retention of sucrose in the prepared paper nanocomposites as compared to the case of unmercerized cotton linters. We assume that regions of the cell wall lamellae, on both sides of the sucrose spacers, are stressed during drying because the sucrose spacers hinder them to relax. This leads to a strain, which makes some microfibrils be partially released and protrude out of the fiber. Thus a sort of fiber beating takes place. We called this phenomenon Incorporation-Beating or Encapsulation-Beating to differentiate it from chemical and mechanical beating; and it explains the great increase in breaking length of the paper nanocomposites prepared from the mercerized non-dried sucrose-loaded linters.

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