Production of polymer materials from renewable raw materials that are interwoven with nature in a natural life cycle is a challenge of our generation. In order to make such materials inexpensive and thus, in a final iteration, useful for society, inexpensive raw materials, such as kraft black liquor, are appealing sources of atmospheric carbon. We developed a method to synthesize liquid, mouldable thermosetting polymers from untreated Kraft Black Liquor and epichlorohydrin, which can be synthesized from glycerol. We will show that bio-based polymers can be produced directly from black liquor coming out of a paper mill without the generation of waste materials. We fully utilized the lignin and were able to produce liquid and solid epoxy resins from it. Suitable curing systems and processes were developed to produce thermosets, which can now be used to manufacture of high performance composites. The mechanical properties of our black liquor epoxy resin were comparable to other bio-based (Green) epoxy resins with Young’s moduli above 1 GPa and a tensile strength of around 40 MPa. Glass transition temperatures of approx. 70°C were measured for this type of material.