Composite Materials Having Natural Granular Materials or Soils and Hydrophobic Biologically-derived Binders

A method of reusing lignin-based composites to make a new recycled lignin-based composite, comprising:

• (a) having recycled lignin-based composite aggregates, wherein the recycled lignin-based composite aggregates are defined as a material obtained from crushing of lignin-based composites at an end of a design life.
• (b) adding a solvent to reactivate a lignin binder on the recycled lignin-based composite aggregates and wherein the solvent has fully been evaporated or dissolved at a temperature less or equal than 60 degrees Celsius, at an atmospheric pressure of less or equal than 1 atmosphere and within 7 days;
• and
• (c) mixing the reactivated lignin-based composite aggregates to reform a new recycled lignin-based composite wherein there is at least 5 percent by mass of lignin in the composite.

A method of enhancing the strength of manufactured lignin-based composites using mixed solvents, comprising:

• (a) using a mixed solvent composed of water and non-aqueous solvents for enhancing a binding strength of a lignin glue;
• (b) dissolving a raw-form of lignin into the mixed solvent, wherein the mixed solvent has been evaporated or dissolved at a temperature less or equal than 60 degrees Celsius, at an atmospheric pressure of less or equal than 1 atmosphere and within 2 days;
• and
• (c) mixing the enhanced lignin-glue with aggregates to form a stronger composite, wherein the enhanced lignin-glue binds to aggregates in a composite, wherein there is at least 5 percent by mass of lignin in the composite.