NOVELTY - Producing a cellulosic feedstock for enzymatic hydrolysis and/or a lignin fraction for chemicals production, comprises: (a) preparing raw material that is lignocellulosic biomass; (b) treating the biomass in hot water; and (c) presenting at least one carbonium ion scavenger in the treatment.    USE - The process is useful for producing cellulosic feedstock for enzymatic hydrolysis and/or lignin fraction for chemicals production; for hot water treatment of lignocellulosic biomass in order to produce sugars from cellulose by enzymatic hydrolysis, preferably for a subsequent fermentation to biofuels; for production of a lignin fraction, where the resulting lignin is used as a raw material for the production of aromatic chemicals, for example by hydrogenation, hydrogenolysis, oxidation or pyrolysis and preferably in the presence of a scavenger; for production of a lignin fraction, where the resulting lignin is used as a raw material for the production of aromatic chemicals, preferably monomers, for example by hydrogenation, hydrogenolysis, oxidation or pyrolysis, which are recycled as single products or as a mixture of products to the hot water treatment stage as carbonium ion scavengers and which can comprise, but are not restrained to: substituted and non-substituted monocyclic compounds like benzene and alkylbenzenes like ethylbenzene, phenol and alkylphenols like 1-methylphenol, guaiacol and alkylguaiacols like 3-methylguaiacol, hydrobenzoic acids like 4-hydrobenzoic acid or vanillic acid, cresols like p-cresol, xylenols like 2,5-xylenol, xylenes like 3-xylene, catechols and alkylcatechols like 3-methyl catechol, anisol and alkylanisoles like 4-methylanisol, non-substituted polycyclic aromatics like naphthalene or pyrene, substituted polycyclic aromatics like alkylated polycyclic aromatics or naphtoles like 2-naphtol; for production of a lignin fraction, which is used as a component in phenol-based polymers; for a targeted lignin product formation by the use of tailor-made carbonium ion scavengers; and for an improved delignification of the biomass in the hot water treatment, preferably under acidic conditions (all claimed).    ADVANTAGE - The invention provides use of scavengers for carbonium ions that are formed in the hot water treatment of lignocellulosic biomass, which can both enhance delignification to produce a highly digestible (ligno)cellulose for enzymatic hydrolysis and can allow the production of a well-defined pre-depolymerized lignin fraction to be exploited in a further reaction step. The invention can enhance the enzymatic digestibility of cellulose by the use of carbonium ion scavengers in the hot water treatment of lignocellulosic biomass; can produce a homogeneous and uncondensed lignin fraction for a subsequent chemicals production; can provide a simultaneous valorization of cellulose and lignin in an integral pretreatment approach; can provide option of a scavenger production in the process from lignin itself; and can provide a low cost and environmentally superior pretreatment process.    DETAILED DESCRIPTION - An INDEPENDENT CLAIM is biomass-product obtainable by the process.