Second-generation bioethanol from industrial wood waste of South American species

VALLEJOS, M.E.; KRUYENISKI, J.; AREA, M.C.

Biofuel Research Journal

Green Wave Publishing of Canada

Año: 2017 vol. 4 p. 654 - 667

There is aglobal interest in replacing fossil fuels with renewable sources of energy. Thepresent review evaluates the significance of South-American wood industrialwastes for bioethanol production. Four countries have been chosen for thisreview, i.e., Argentina, Brazil, Chile, and Uruguay, based on their current orpotential forestry industry. It should be noted that although Brazil has aglobal bioethanol market share of 25%, its production is mainlyfirst-generation bioethanol from sugarcane. The situation in the othercountries is even worse, in spite of the fact that they have regulatoryframeworks in place already allowing the substitution of a percentage ofgasoline by ethanol. Pines and eucalyptus are the usually forested plants inthese countries, and their industrial wastes, as chips and sawdust, could serveas promising raw materials to produce second-generation bioethanol in thecontext of a forest biorefinery. The process to convert woody biomass involvesthree stages: pretreatment, enzymatic saccharification, and fermentation. Theoperational conditions of the pretreatment method used are generally definedaccording to the physical and chemical characteristics of the raw materials andsubsequently determine the characteristics of the treated substrates. Thisarticle also reviews and discusses the available pretreatment technologies foreucalyptus and pines applicable to South-American industrial wood wastes, theirenzymatic hydrolysis yields, and the feasibility of implementing such processesin the mentioned countries in the frame of a biorefinery.