resumo
Sulphite spent liquor (SSL) is a side product from acidic sulphite pulping of wood, which organic counterpart is composed mainly by lignosulphonates (LS) and sugars. The last are a prominent substrate for the bioprocessing although a previous purification step is necessary to eliminate microbial inhibitors. In this study a fractionation of hardwood SSL (HSSL) has been accomplished employing ion exchange resins in order to separate sugars fraction from concomitant inhibitors: LS, acetic acid, furan derivatives, phenolics, acetic acid and excess of inorganic salts. The fractionation of HSSL has been carried out using two fixed-bed ion exchangers in series (cationic + anionic). The first cation exchange column packed with Dowex 50WX2 resin was able to eliminate free cations and partially separate sugars from high molecular weight LS and furan derivatives. The second anion exchange column packed with Amberlite IRA-96 sorbed remaining LS, phenolics and acetic acid. Overall, the series arrangement under investigation has removed 99.99% of Mg2+, 99.0% of Ca2+, 99.6% of LS, and 100% of acetic acid, whereas the yield of recovered sugars was at least 72% of their total amount in HSSL. (C) 2012 Elsevier B.V. All rights reserved.
palavras-chave
EUCALYPTUS-GLOBULUS; ETHANOL-PRODUCTION; PICHIA-STIPITIS; BIOETHANOL; LIGNOCELLULOSE; BIOREFINERIES; PRODUCTS; HARDWOOD; XYLOSE
categoria
Biotechnology & Applied Microbiology
autores
Fernandes, DLA; Silva, CM; Xavier, AMRB; Evtuguin, DV
nossos autores
Ana Maria Rebelo Barreto Xavier
Professor Auxiliar
Carlos Manuel Silva
Professor associado
Dmitry Evtyugin
Professor Associado com Agregaçãoagradecimentos
Authors thank the Portuguese Foundation for Science and Technology (FCT) for the financial support of this work (post-doctoral grant SFRH/BPD/65482/2009 attributed to D. L. A. Fernandes, and Financing Programme Pest-C/CTM/LA0011/2011) and CAIMA, Industria de Celulose S.A., Constancia, Portugal for the HSSL liquor and technical assistance during this work.