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Legno

Legno. Pulping. Processo chemiotermomeccanico (solfito diluito; calore moderato; pressione; azione meccanica). Processo Kraft (Calore, solfuro sodico, basi). Lignina (80%), black liquor (fenoli). cellulosa. ENERGIA. Prodotti ad alto valore aggiunto. Sbianca. Carta. stampa. giornali.

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Legno

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  1. Legno Pulping Processo chemiotermomeccanico (solfito diluito; calore moderato; pressione; azione meccanica) Processo Kraft (Calore, solfuro sodico, basi) Lignina (80%), black liquor (fenoli) cellulosa ENERGIA Prodotti ad alto valore aggiunto Sbianca Carta stampa giornali Disinchiostrazione IMBALLAGGI Carta riciclata

  2. INDUSTRIA CARTARIA EUROPEA: DIMINUIRE costi + AUMENTARE competitività + MANTENERE elevate produzioni Utilizzo SOSTENIBILE di risorse rinnovabili Nuove tecnologie: BIOTECNOLOGIE, ENZIMI • Perché sia implementato, un nuovo processo deve essere: • efficiente; • economicamente interessante (costi enzima e downstream); • privo di barriere tecniche (pH, T a cui usare enzima) (si accetta enzima se non occorre cambiare le condizioni del processo)

  3. Legno Pulping Processo chemiotermomeccanico (solfito diluito; calore moderato; pressione; azione meccanica) Processo Kraft (Calore, solfuro sodico, basi) Lignina (80%), black liquor (fenoli) cellulosa ENERGIA Prodotti ad alto valore aggiunto Sbianca Carta stampa giornali Disinchiostrazione IMBALLAGGI Carta riciclata

  4. BIOTECHNOCAL TOOLS FOR FIBRE MATERIAL ENGINEERING Application Tools Potential substrate Action Mechanisms of in wood pulp modification Enzymes Cellulases Cellulose Xylanase Xylan Mannanase Glucomannan Lipases Triglycerides Oxidases - Laccase Lignin, lignan in DCS - Peroxidase Lignin, lignan in DCS - Tyrosinase Lignin ? - Galactose oxidase Galactoglucomannans in fibres and in DCS Transferases Hemicelluloses Esterases (e.g. XET) etc. Proteins hydrophobins Binding to surfaces Incerased hydrophobisity Process aids? Hydrophobisation? swollenins Cellulose Loosening of cellulose fibril structure? Fibre engineering? Specific hydrolysis Surface specific action Process aids &Specific hydrolysis Surface specific peeling analytical tools Specific hydrolysis Surface specific peeling - " - Specific hydrolysis Removal of extractives - " - Process aids & functionalisation - " - - " - - " - Functionalisation Formation of radicals Covalent linkage due Formation of radicals to radical reaction Formation of quinone Quinone based linkages Formation of ketones Ketone and its further reactions Transfer reactions Transfer of activated of esterases etc. group

  5. SBIANCA Agenti clorurati; H2O2, O3 • PRE-SBIANCA: XILANASI • rottura legami covalenti • lignina-emicellulose • > accesso a lignina • combinate + trattamenti ciclici  ottimi risultati (riciclare enzima) • nuove: da termofili e alcalofili; • DNA ricombinante • studi di struttura-attività enzima

  6. Disinchiostrazione: Cellulasi (modificate; separano inchiostro da fibre) + surfattanti • Rimozione Stickies: • polimeri (resine acriliche, polivinilacetato, PE, PP) da adesivi, inchiostri, film plastici; formano agglomerati con le fibre; riducono qualità carta, rallentano tempo macchina • Rimozione meccanica (centrifugazione) • Controllo carta in entrata • Agenti chimici • Enzimi lipolitici prima/durante pulping + adsorbenti (bentonite, …) • lipasi, proteasi, emicellulasi, amilasi(Bork, K., et al., 2002. WO02095127); • laccasi(ICBPP 10, Wisconsin, USA, 10-15 June 2007)

  7. Rimozione depositi microbici: Slime aerobico/anaerobico da acque riciclate causa blocco macchine; Biocidi per prevenire formazione matrice (proteasi, lipasi, amilasi) Detossificazione acque di cartiera: Laccasi per degradare fenoli e derivati di lignina in black liquor (FONT, X., et al., 2003. J Chem Technol Biotechnol, 78, 548–554)

  8. Laccasi Ridotta Lignina Ridotta Mediatore Ossidato O2 2 H2O Lignina Ossidata Laccasi Ossidata Mediatore Ridotto • Lignina perossidasi, • Manganese perossidasi • trattamento con funghi • (ARCHIBALD, F.S. et al., 1997. J Biotechnol, 53, 215–236) • MnP  H2O2  > brillantezza carta • combinazioni MnP – xilanasi • Laccasi • facile produzione; in commercio • alcali  laccasi; xilanasi  laccasi (ICBPP 10, Wisconsin, USA, 10-15 June 2007) • nuove laccasi (Azospirillum spp, Bacillus subtilis); nuovi mediatori

  9. LACCASI • Laccases catalyse the oxidation of diphenols, substituted phenols, polyphenols, amines, and many others including fibre bound lignin • Laccases can be used to activate, i.e. radicalise, the surface lignin of lignin-rich wood pulps • O OH O - - e e laccase OH OH O O2 + 4e- + 4H+ 2 H2O Non-enzymatic reactions

  10. Brunow et al., 1998 A STRUCTURAL SCHEME FOR SOFTWOOD LIGNIN FRAGMENTS Laccase oxidation of lignin Phenoxy radical formation • Depolymerisation • Polymerisation

  11. CHEMO-ENZYMATIC FUNCTIONALIZATION OF FIBRES PRINCIPLE OF THE METHOD Bonding of functional chemistry to activated fibre surfaces • Modification occurs via surface lignin • Activation by enzymatic or chemical means • Based on fast radical reactions METHOD CAN BE EXPLOITED IN • Enhancing inherent fibre properties • Creating completely new fibre properties Lignin on TMP fibre

  12. FUNCTIONALISATION OF FIBRES BY CHEMO-ENZYMATIC MEANS Enzymatic/chemical oxidation of fibres Enzymatic/chemical oxidation of additives Activation of fibres Activation of additives Tailor-made fibres

  13. 1. 2. 3. fibre FUNCTIONALISATION OF FIBRES = Component with selected properties = Linker component between fibre and component with selected properties

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