Method for obtaining a stable lignin: polar organic solvent composition via mild solvolytic modifications

A crude lignin oil (CLO), comprising:

• a reaction lignin product obtained by solvolysis of a solid feedstock containing lignin in a polar organic solvent,
• wherein the polar organic solvent is an alcohol, a ketone or an ester, or a combination thereof,
• wherein the ratio between the reaction lignin product and said polar organic solvent is in a range 1:1-1:2 g/ml,
• wherein the CLO has a weight average molecular weight (Mw) in a range between 1,000-2,000 daltons with a polydispersity index in a range between 2.1-3,
• wherein the reaction lignin product has a form that is partially depolymerized whereby some ether linkages have been cleaved and the lignin has been broken down into oligomers,
• wherein the reaction lignin product is solubilized in the polar organic solvent;
• and
• wherein the CLO comprises the entire post-solvolysis liquid phase of the reaction lignin product in the polar organic solvent,
• wherein the entire post-solvolysis liquid phase is the only entire post-solvolysis liquid phase of the CLO;
• wherein water is present in an amount of less than 10 wt. % relative to the CLO;
• wherein the CLO can be used as fuel;
• and
• wherein the CLO has a number average molecular weight (Mn) less than about 625.