The SKZ Plastics Center launches a new research project “CloseT” with the Fraunhofer Institute for Manufacturing Technology and Applied Materials Research IFAM to develop an industrially viable, continuous chemical recycling process using solvolysis for recycling mixed waste textile fibers.

“We want to create a sustainable alternative that not only conserves resources but also opens up new value chains,” explained Dr. Hatice Malatyali, project manager at SKZ.

Sampling of reaction products from the continuous chemical recycling process.

The chemical recycling process with solvolysis involves mixing old textile fibers in a continuous process using a twin-screw extruder. The reaction products obtained in the recycling process are to be used directly as raw materials in plastics processing.

Suitable synthesis routes are first developed in the laboratory and then transferred to the continuous process. One focus is on the efficient separation of mixed fibers such as cotton and PET. Cellulose acetate is to be produced from the cellulose fibers obtained, while the degraded PET fractions are repolymerized to rPET.

The “CloseT” research project will be funded by the Volkswagen Foundation from November 1, 2025, to October 31, 2029, through the “Circularity with Recycled and Biogenic Raw Materials” funding initiative.

The SKZ Plastics Center launches a new research project “CloseT” with the Fraunhofer Institute for Manufacturing Technology and Applied Materials Research IFAM to develop an industrially viable, continuous chemical recycling process using solvolysis for recycling mixed waste textile fibers.

“We want to create a sustainable alternative that not only conserves resources but also opens up new value chains,” explained Dr. Hatice Malatyali, project manager at SKZ.

Sampling of reaction products from the continuous chemical recycling process.

The chemical recycling process with solvolysis involves mixing old textile fibers in a continuous process using a twin-screw extruder. The reaction products obtained in the recycling process are to be used directly as raw materials in plastics processing.

Suitable synthesis routes are first developed in the laboratory and then transferred to the continuous process. One focus is on the efficient separation of mixed fibers such as cotton and PET. Cellulose acetate is to be produced from the cellulose fibers obtained, while the degraded PET fractions are repolymerized to rPET.

The “CloseT” research project will be funded by the Volkswagen Foundation from November 1, 2025, to October 31, 2029, through the “Circularity with Recycled and Biogenic Raw Materials” funding initiative.