Hydrothermal Liquefaction of Specialty Plastics

Open Access
- Author:
- Villacis, Bianca
- Area of Honors:
- Chemical Engineering
- Degree:
- Bachelor of Science
- Document Type:
- Thesis
- Thesis Supervisors:
- Phillip E Savage, Thesis Supervisor
Scott Thomas Milner, Thesis Honors Advisor - Keywords:
- PLASTIC
POLYMERS
HTL - Abstract:
- Hydrothermal liquefaction (HTL) was performed on Nylon 6 (NY), Nylon 6,6 (NY 6,6), Polysulfone (PSU), Polystyrene (PS), Polylactic acid (PLA), and Poly(styrene-co-acrylonitrile) (SAN) for 30 minutes to produce oil. Each plastic underwent HTL at 350℃ and 425℃ to examine temperature effects on oil yield. At 350℃, NY, PS, SAN, and PSU produced oil yields above 20%, and only PS, PSU, and SAN produced oil yields above 20% at 425℃. Increasing the HTL temperature from 350℃ to 425℃ resulted in many of the plastics producing decreased oil yields which is likely a result of decomposition and the formation of gaseous products. GC-MS analysis showed that the oil phases of NY contained caprolactam (the monomer form of NY), NY 6,6 contained cyclic ketones, PS, SAN, and PSU contained aromatic compounds and PLA contained alcohols, esters, and carboxylic acid containing compounds. HTL of mixtures containing 50 wt% of each plastic with polypropylene (PP) and cellulose were examined to see if interactions between the plastics with PP and cellulose would affect the oil yields obtained. It was determined that interactions between PP and the plastics were not significant at 350℃, but both synergistic and antagonistic interactions between mixtures of these plastics and cellulose were both observed under HTL conditions at 350℃.