Introduction

One of the main issues in circular economy is facing the recovery of end-of-life rubber mix and plastic waste (plasmix). The sector is progressively moving away from inefficient mechanical systems, towards chemical recovery. These technologies are able to convert the vulcanized rubbers into more useful gases and liquids, but some areas of recovery remain extremely limited. In particular, tyres do not fall into the chemically recyclable categories, due to the significant presence of sulphur. In thermo-chemical treatments, sulphur is released from vulcanised matrices mainly in the form of H2S, a toxic (lethal) and energy intensive compound.

Technical features

The patent allows you to selectively extract the sulfur content from vulcanized rubbers, prepare the desulfurized plastics for chemical recovery treatments and completely recover the hydrogen necessary for desulfurization. A new process for the chemical conversion of rubber mixes, but also of plastics, also known as plasmix. A process and a relative plant have been conceived that allow the chemical recovery of the tires, allowing their high efficiency conversion into chemical products with high added value, as well as reducing the waste produced and maintaining a high level of safety. Tires are plasmix with relevant sulfur content (6%). The technology has a TRL 3.

Possible Applications

• Tyre treatment;
• Recycling of other types of vulcanised rubbers;
• Deep sulphur cleaning;
• Combination with plastix chemical recycling;
• Vulcanized rubbers into plasmix.

Advantages

• Efficient and selective management of Sulphur by transformation into H2S during devulcanisation;
• Reduced emissions;
• Self-sustaining loop for hydrogen utilization;
• Energetically self-sustainable;
• Possibility of combining vulcanised rubbers with plastics for chemical recycling.