In order to improve sorption properties of hydrolysis lignin - reach-in-lignin non-hydrolyzed residue after fuel ethanol production by enzymatic hydrolysis of softwood, mechano-chemical modification and sol-gel process were carried out, using a Si-containing oligomers as modifiers. For both modification methods 29Si NMR spectroscopy data show that the Si-component of composites forms condensed silica network with condensation degree of about 80%, which contains rather significant amount of Si-OH groups important for adsorption interactions with metal ions. The composites obtained via sol-gel process differ by enhanced hydrophobicity and more developed porosity than those obtained by mechano-chemical process and the parent lignin. Adsorption efficiency towards heavy metals, e.g. Cd2+, achieved in the case of diluted solutions practically 100%, whereas for the parent lignin this value was about 40%. In comparison with the parent lignin, Cd2+ and Mn2+ adsorption capacity were increased in 1.5-2 times, but Cu2+ in 3-6 times. Process of heavy metals adsorption depends on the mode of lignin modification and follows the Langmuir model and the Freundlich model, respectively, for composites obtained by the sol-gel process and the mechano-chemical treatment.