US 11,986,750 B2
Reducing surface and bulk contamination in plastic
Norman Scott Broyles, Hamilton, OH (US); Dimitris Ioannis Collias, Mason, OH (US); and Anthony Frederick Cappel, Cincinnati, OH (US)
Assigned to The Procter & Gamble Company, Cincinnati, OH (US)
Filed by The Procter & Gamble Company, Cincinnati, OH (US)
Filed on Feb. 27, 2023, as Appl. No. 18/114,412.
Application 18/114,412 is a continuation of application No. 17/229,903, filed on Apr. 14, 2021, granted, now 11,628,379.
Claims priority of provisional application 63/010,078, filed on Apr. 15, 2020.
Prior Publication US 2023/0219016 A1, Jul. 13, 2023
Int. Cl. C08J 11/08 (2006.01); B01D 11/02 (2006.01); B08B 3/04 (2006.01); B29B 17/00 (2006.01); B29B 17/02 (2006.01); B29K 105/26 (2006.01); C08J 7/02 (2006.01)
CPC B01D 11/0288 (2013.01) [B01D 11/0203 (2013.01); B08B 3/04 (2013.01); B29B 17/00 (2013.01); C08J 11/08 (2013.01); B01D 11/0292 (2013.01); B08B 2220/00 (2013.01); B08B 2240/00 (2013.01); B29B 2017/0015 (2013.01); B29B 2017/0289 (2013.01); B29B 2017/0293 (2013.01); B29K 2105/26 (2013.01); C08J 7/02 (2013.01); C08J 2300/30 (2013.01)] 11 Claims
 
1. A method to extract contaminates from a first plastic to produce a purer plastic comprising:
a. providing a first plastic comprising individual contaminants, each individual contaminant having a concentration;
b. extracting said individual contaminates from said first plastic at a temperature and a pressure, using a leaching solvent that is at least one of THF, di-ethyl ether, hexanes, acetone, ethanol, methanol, propanol, iso-propanol, MEK, methylene chloride, or Ethyl Acetate, in extraction stages, wherein the total extraction time is less than about 6 hours, to produce a purer plastic comprising individual contaminates, each having a concentration;
wherein said extraction is flooded leaching wherein said temperature is between about 20 and 90 C; wherein said extraction stages are conducted at a leaching solvent to first plastic mass ratio; wherein said a leaching solvent to first plastic mass ratio per stage is greater than about 5:1 but less than 100:1; wherein said pressure is between about atmospheric and 1,000 atm; wherein said first plastic individual contaminants comprise at least one of 4-tertpentylphenol, bisphenol A, OCDD, PCB 118, and 2-ethylhexyl phthalate; wherein each individual contaminants concentration in said purer plastic is reduced compared to each individual contaminants concentration in said first plastic; and wherein the average of said reductions of said concentrations of said first plastic contaminants to said purer plastic contaminants is at least about 55% or LOQ; and
wherein the leaching solvent should not significantly dissolve the first plastic at the temperature and pressure of the process.