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Toxics Use Reduction Institute · Surface Solutions Laboratory
 
Toxics Use Reduction Institute




Surface Solutions Laboratory

Trial Report



Trial Number 0

(Client Number 236, Project Number 1)

Trial Purpose: To identify alternatives for dissolving poly styrene.

Date Run: 01/03/05

Experiment Procedure:
Five alternative solvents were selected from the laboratory's database of test results based on client supplied information. Each product was used at full strength at room temperature. One polystyrene pellet was placed into each solution and the amount of time required for dissolving the styrene was recorded. Results from the alternatives were compared directly with one of the current solvents (Toluene).

Trial Results
Three of the five alternatives dissolved the poly styrene in less than one minute. A fourth product started to dissolve the styrene but did not
complete the process after 30 minutes. The fifth alternative showed no signs of dissolving the material. The effective alternatives were all slower
than toluene. Toluene dissolved the material in under 5 seconds.


Success Rating
Results suggest a scale-up feasible match for cleaning chemistry and equipment. Pilot plant study with actual parts recommended.

Conclusion
DBE is a relatively safe environmentally friendly solvent that dissolves a number of resins and plastics such as polystyrene. This makes the use of DBE attractive as a solvent for many plastics recycling applications. Partial solubility in water can lead to precipitation options for polymer recovery in an aqueous phase, and DBE itself can be recovered by vacuum distillation. DuPont is currently supporting several polymer-recycling projects (http://dbe.invista.com/).

Florida Chemical?s technical grade d-Limonene has been found to be an effective solvent for dissolving and compacting expanded polystyrene (EPS). D-Limonene (also know as orange terrenes) is a biodegradable solvent and degreaser occurring in nature as the main component in citrus peel oil. D-Limonene resembles the chemical structure of polystyrene and can rapidly break down the chemical bonds of EPS. The EPS pieces are floated on the surface of the d-Limonene until dissolved. The process can be accelerated by spraying d-Limonene directly onto the EPS. Florida Chemical has determined that between 300 kilograms and 400 kilograms of EPS can be dissolved in 100 kilograms of technical grade d-Limonene. (http://www.floridachemical.com/d-limonenestyrofoamrecycling.htm)

Bio Chem Systems Bio T Max is another d-limonene solvent and can be used in the same method as mentioned above (http://www.biochemsys.com/).