Catalytic Pyrolysis Study

This Study seems to be on behalf of the KSA (Kingdom of Saudi Arabia) reaching towards goal of an energy circular economy. Natural Zeolite is a cheap local product there and they wanted to try it out.

In the Catalytic process, the catalytic process enhances the target pyrolysis reactions and reduces reaction times and temperature, improves the liquid oil quality and increased the overall process efficiency (quote from a 2012 article).

• The surface area, acidity,, porce size and volume are key features of the catalyst: list of catalysts tried:
• FCC, cilica alumina, MCM-41, and zeolites like Y-zeolite, HZSM, and ZSM-5
• -FCC microporuse increases liquids, ZSM-5 increases gas yield due to mesoporus structure.
• Microporus catalysts linit the entrance of higher Hydrocarbons
• High acidity catalysts increase liquid and decrease gases (2016 study)
• Zeolite is a new catalyst and is not in many studies ( The Italians I did an article about say they are using zeolite)
• The study aims to study the effects of catalysts against various plastic types.

Table 1 shows that the various plastics received the same treatments.

Page 5 -Table 2 of the article shows the results:

In summary:

In the presence of Synthetic Zeolite compare (S) to Natural Zeolite (N)

PS-Mostly oil,                    N is better
PP- Mostly Gas                  N is better
PE- Mixed                         N did much worse than S
PS/PP even mix                N and  S close to the same
PS/PE  even mix                N and S about the same
PP/PE   Way more Gas      N and S about the same
PS/PE/PP                           S way more liquid than N
PS/PE/PP/PET                   N mostly Char - S about half Liquid

Table 3 (page 6) Shows the Types of Hydro carbons that were in the liquid oil from plastic types.
It shows the liquids as much lower overall than our experience, and mostly aromatics -a lot of the dreaded benzene. Also the Hyrdro carbon types in the liquid seemed to vary a lot between the use of N or Z catalyst

a lot of stuff about test methods, then on page 8
 an analysis of Hydrocarbon types per plastic type, in the liquids

PS-                                     Mostly Ethylbenzen
PP-                                     even mix
PE-                                     2x as much styrene as the rest, but very low yields
PS/PP                                 2x as much Benzene/Proply/benzene as Styrene, the rest mixed-high yield
PS/PE                                 even mix
PP/PE                                 1/3 benzinedicarboxylic 1/6 azulene the rest a mix
PS/PE/PP                           even mix, a little higher on the Benzene, low yield
PS/PE/PP/PET                   half of the total benzinedicarboxylic the rest a mix

They used a spectrum analyzer on the peak phenol and alcohol types and broke them down further on page 9.Then they did a wave table analysis of the spectrum frequencies on page 10. I'm out of my league here for interpretation. These seem to be about Alkenes (olefins). I remember Tommy told me those were a bad thing for us.

The HHV  (energy value) in all these fuels were in the low to mid 40 Milijules per Kilogram
 (table 4 page 11) This was considered very good.

Conclusions

• all liquids produced required further treatment for use as conventional transport
• He quoted a 2015 Study that mixed plastic Py oil with other fuels showed a 20% blend was equivalent to conventional diesel.an increase of 13-17% reduced engine performance.
• Recovery of high quality Aromatics (Naptha) should be monetized
•  This is valuable fuel and will contribute to a circular fuel and emissions economy

Future Study

• Zeolite Natural Catalyst was adequate but better Synthetics treatments  that increase surface area and structure, like acid leaching, thermal treatment  or wet application .
• They swill study activating the Char to use as a catalyst in the future

My conclusions:

• I wonder if this was funded by someone with a stake in Zeolite
• I wish they had done a true control at each phase, comparing these studies to Non-catalytic Plastic Pyrolysis. 
• We get better liquid/gas ratios than they did with almost all plastics without the catalysts. So we may be way ahead of them there.
• Different plastic mixes produce different mixes of of  liquid to gas in presence of this catalyst, and the use of catalysts could enhance those differences for our projects.
• We should re-look at how we might monetize aromatics like naptha or cycle them back in to improve our liquid fuel value.
• Olefins continue to be an issue for review.
• Even the Saudis agree that plastic Pyrolysis has a place in their fuel economy-good news in a place of cheap oil.
• After we get our first production plant up and running we should create a budget for R&D to study a schedule of Catalysts to enhance our fuel/gas mixes for different projects.