Efficient methods and compositions for recovery of products from organic acid pretreatment of plant materials

A method for producing a hemicellulosic juice the method comprising the steps of:

• a) introducing a hemicellulosic mixture comprised of dissolved hemicellulose,
• organic acids, and water and other constituents produced by organic acids pretreatment of plant material into a multi-effect evaporation system, wherein the multi-effect evaporation system comprises a first effect evaporator and a last effect evaporator, wherein the content of the organic acids in the hemicellulosic mixture is 10% to 30% by weight, and
• b) evaporating the hemicellulosic mixture within the multi-effect evaporation system to form a concentrated hemicellulosic juice with a dry matter content of 40% to 70% by weight, and
• c) removing organic acids from the concentrated hemicellulosic juice in a stripping column to form a hemicellulosic juice, wherein the hemicellulosic juice comprises less than 2% by weight organic acids,
• wherein the stripping column utilizes direct steam as a stripping agent.