14/2017 - 2017
PET is a transparent, lightweight plastic with high stability and persistence. It is used for a wide area of application. You can find PET in clothing, bottles or food packaging, in adhesive tapes, packaging trays and blister packs. PET is also used as a substrate in thin film solar cells. The production is petroleum based – 1.9 kg crude oil is necessary to produce 1 kg PET. For minimising the use of natural sources the recycling of PET is a well-established approach. In addition, less energy is required to manufacture recycled material.
In 1977 the first PET bottle was recycled in the US, and nowadays bottle recycling is practiced all over the world.
An effective detergent is essential for removing soil, fat, oil, etc. In addition, alkali supports the process and helps to remove adhesives and labels. Furthermore, the washing temperature plays an important role.
If a surfactant is added to the water, the air bubbles arising on the surface of the liquid are far more stable. This is due to the surfactants‘ structure, which deposits at the liquid/gaseous interface. This reduces the interface tension and thus stabilises the foam.
Sink-float processes are used to separate different materials in PET recycling. Due to different density, PET with a density of 1.35-1.40 g/cm3 has the tendency to sink to the bottom and polyolefins, e.g. PE with a density of 0.91-0.97 g/cm3 swims at the surface.Zurück Bestellen