Selective Dissolution and Recovery Technology for Vinyl Chloride Resin: A Shift in Separation Technology in Response to the Era of Mixed Waste Materials Late 1990s to Early 2000s

Selective Dissolution and Recovery Technology for Vinyl Chloride Resin: A Shift in Separation Technology in Response to the Era of Mixed Waste Materials Late 1990s to Early 2000s
The technology for selective dissolution and recovery of vinyl chloride resin attracted attention from the late 1990s to the early 2000s, as the limits of recycling construction waste became clear. This technique, in which special chemicals are added to vinyl chloride products to selectively dissolve and recover only the resin components, was developed in Europe ahead of other countries, and was at the stage of being considered for demonstration introduction in Japan as well.

At the time, a large amount of vinyl chloride resin was being used mainly in the field of building materials, such as flooring, wall materials, piping, and electric wire sheathing, and a large amount of it was beginning to be discharged as mixed waste with the increase in building demolition. However, because of the complex mixture of wood, metal, insulation, adhesives, and other materials, it was difficult to recycle the waste by mechanical sorting, and much of it was sent to incineration or landfill.

In response to this situation, selective dissolution and recovery technology has brought about a change in thinking, replacing the sorting process with chemical separation. The technology has the potential to solve the technical bottleneck of construction plastic recycling because it can remove only vinyl chloride resin even when different materials are mixed together. The resin obtained through dissolution and re-precipitation is of high purity, and it is possible to return it to construction material applications.

In the early 2000s, Japan's Construction Recycling Law was about to come into effect, and increasing the recycling rate was a policy issue. The environmental impact of incinerating chlorine-containing vinyl chloride (PVC) was seen as a problem, and selective dissolution technology attracted attention as a way to shift away from dependence on incineration. On the other hand, there were issues such as chemical management, cost, and safety, and at that time, this technology was often positioned as a complementary technology specialized for building material waste that was difficult to sort. Nevertheless, this technology was important in that it presented a new separation concept for the era of mixed waste materials.