Processes of treating cellulosic material

A process of producing a fermentation product from pretreated cellulosic material, comprising the steps of:

• i) preconditioning said pretreated cellulosic material;
• ii) hydrolyzing said cellulosic material of step i) in the presence of a cellulolytic enzyme preparation to produce sugars;
• iii) fermenting said sugars of step ii) in the presence of a microorganism to produce said fermentation product;
• wherein a solid-liquid separation step, resulting in a solid fraction and a liquid fraction, is carried out:
• a) after preconditioning step i), but before hydrolyzing step ii);
• or
• b) after hydrolyzing step ii), but before fermenting step iii);
• wherein a phenol oxidizing enzyme is present or added:
• during preconditioning step i);
• or
• after preconditioning step i), but before hydrolyzing step ii);
• or
• during hydrolyzing step ii);
• wherein a hemicellulase is present or added:
• during preconditioning step i);
• or
• after preconditioning step i), but before hydrolyzing step ii);
• or
• during hydrolyzing step ii)
• wherein said solid-liquid separation step is carried out after said cellulosic material is subjected to said phenol oxidizing enzyme and said hemicellulase;
• and wherein separation into the solid fraction and the liquid fraction is improved as compared to the same process where said phenol oxidizing enzyme and said hemicellulase are not present or added.