The TSC SB RAS researchers introduced carbide-containing materials produced using plastic waste

The researchers of the Tomsk Scientific Center produced valuable titanium carbides using the highly exothermic reaction between PET bottles and Ti powder as well as a hydrogen-containing gaseous by-product which can be used as fuel for heat and power units. These carbides are similar in their properties to the reference ones. The research is published in Green Chemical Engineering.

– About 300 million tons of plastic products for different purposes are manufactured every year. It is known that only 12 % of plastic waste is recycled, while another part is disposed of in a landfill. It is thus necessary to develop new technologies associated with the stable development of chemical engineering. These technologies will allow us to recycle completely and cost-effectively plastic wastes in an environmentally friendly manner, – says study author Alexey Matveev, a researcher of the TSC SB RAS.

The idea is to use self-propagating high-temperature synthesis (SHS) methods. Ti powder and PET bottles were used for this study. They were preliminary ground to fine flakes less than 1 cm in size. The next step was the preparation of Ti-PET core-shell particles. Then, the powder batch of Ti-PET particles were placed in a special vacuum chamber where an exothermic reaction occurred. Reactions with a PET content of 33.3 wt% to 45 wt% at temperatures above 2000 degrees Celsius were optimal. Reactions with such parameters made it possible to produce titanium carbides whose phase composition was close to that of the reference ones.

Titanium carbide powder is used as a base for abrasive pastes, a coating material for steel products and as an independent material for the manufacturing of porous products (filters, burners, etc.), as well as a component of master alloy for the hardening of aluminum alloys. Its price is about 4,000 rubles per kilogram.

The data obtained in this study will be the basis for a new ECO-technology for the synthesis of materials based on various carbides using plastic waste as a feedstock. The results of our research will contribute to the stable development of chemical engineering and the development of a new direction in this field, namely highly exothermic reactive synthesis of materials using plastic waste and secondary materials and to produce other environment-friendly and cost-effective carbide-containing materials.

In addition, the analysis of the gaseous by-products as a result of the exothermic reaction showed that they contained 46 % hydrogen and 37 % carbon monoxide. We believe that these by-products can be used as a fuel for energy generation devices with the higher fuel interchangeability potential, such as radiant burner, rotary engine, etc.