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Systems and methods for recycling waste plastic can convert the waste plastic into a form of purified crude oil that includes one or more organic molecular species and that is free, or substantially free, of impurities such as acids and metals. In some systems and methods, the plastic is heated unde

Systems and methods for recycling waste plastic can convert the waste plastic into a form of purified crude oil that includes one or more organic molecular species and that is free, or substantially free, of impurities such as acids and metals. In some systems and methods, the plastic is heated under vacuum conditions to effect depolymerization of the plastic, which yields a vapor, and the vapor is then directly contacted with a pH adjusted solution in a vapor treatment system. In some systems and methods, a continuous batch process is employed.

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1. A method of recycling plastic, the method comprising: heating a container that has a plastic feedstock therein so as to effect depolymerization of the plastic feedstock;removing a vapor from the heated container, wherein the vapor comprises a gaseous organic species and a gaseous inorganic specie

1. A method of recycling plastic, the method comprising: heating a container that has a plastic feedstock therein so as to effect depolymerization of the plastic feedstock;removing a vapor from the heated container, wherein the vapor comprises a gaseous organic species and a gaseous inorganic species;directly contacting the vapor with a pH adjusted solution so as to condense the organic species; andseparating the condensed organic species from the inorganic species. 2. The method of claim 1, wherein directly contacting the vapor with the pH adjusted solution causes absorption of the inorganic species into the solution. 3. The method of claim 2, wherein the condensed organic species is less dense than water and is hydrophobic, and wherein separating the condensed organic species from the inorganic species comprises retaining the condensed organic species and the pH adjusted solution into which the inorganic species has been absorbed in a common tank. 4. The method of claim 3, wherein separating the condensed organic species from the inorganic species further comprises permitting at least a portion of the condensed organic species to flow over an upper edge of the tank while retaining the pH adjusted solution into which the inorganic species has been absorbed within the tank. 5. The method of claim 3, further comprising introducing at least a portion of the condensed organic species that has been separated from the inorganic species into a settling tank to permit further additional pH adjusted solution to be separated from the condensed organic species. 6. The method of claim 5, further comprising returning pH adjusted solution that has separated from the condensed organic species back to the tank. 7. The method of claim 1, wherein said directly contacting the vapor with a pH adjusted solution comprises bubbling the vapor through the pH adjusted solution. 8. The method of claim 1, wherein said directly contacting the vapor with a pH adjusted solution comprises spraying the vapor with the pH adjusted solution. 9. The method of claim 8, wherein the condensed organic species is less dense than water and is hydrophobic and wherein separating the condensed organic species from the inorganic species comprises retaining the condensed organic species and the pH adjusted solution into which the inorganic species has been absorbed in a common tank, the method further comprising using the pH adjusted solution into which the inorganic species has been absorbed to spray additional vapor that has been removed from a heated container. 10. The method of claim 1, wherein the organic species comprises a class of non-polar organic molecules. 11. The method of claim 10, wherein the class of non-polar organic molecules is a paraffin, an olefin, a naphthene, or an aromatic. 12. The method of claim 10, wherein the vapor further comprises a species of polar organic molecules that at least partially partition into the pH adjusted solution, and wherein the method further comprises separating the non-polar organic molecules from the portion of the polar organic molecules that has partitioned into the pH adjusted solution. 13. The method of claim 12, wherein the polar organic molecules comprise one or more of an alcohol, a ketone, an ether, a phenol, and a carboxylic acid. 14. The method of claim 1, wherein the organic species comprises a class of polar organic molecules. 15. The method of claim 1, wherein the vapor further comprises one or more of an entrained metal species and an entrained metalloid species, the method further comprising separating the condensed organic species from the one or more entrained species. 16. The method of claim 15, wherein directly contacting the vapor with the pH adjusted solution causes absorption of the one or more entrained species into the solution, wherein the condensed organic species is less dense than water and is hydrophobic, and wherein separating the condensed organic species from the one or more entrained species comprises retaining the condensed organic species and the pH adjusted solution into which the one or more entrained species have been absorbed in a common tank. 17. The method of claim 1, wherein the vapor further comprises one or more species of acid molecules, the method further comprising separating the condensed organic species from the one or more species of acid molecules. 18. The method of claim 17, wherein directly contacting the vapor with the pH adjusted solution causes absorption of the one or more species of acid molecules into the solution, wherein the condensed organic species is less dense than water and is hydrophobic, and wherein separating the condensed organic species from the one or more species of acid molecules comprises retaining the condensed organic species and the pH adjusted solution into which the one or more species of acid molecules have been absorbed in a common tank. 19. The method of claim 17, wherein the one or more species of acid molecules comprise at least one of inorganic and organic acid molecules. 20. The method of claim 19, wherein the one or more species of acid molecules comprise at least one of hydrochloric acid, hydrobromic acid, and terephthalic acid. 21. The method of claim 1, wherein the pH adjusted solution comprises an acid. 22. The method of claim 1, wherein at least a portion of the vapor that is directly contacted by the pH adjusted solution remains uncondensed, the method further comprising delivering the uncondensed portion of the vapor to a caustic scrubber. 23. The method of claim 1, further comprising: removing additional vapor from additional containers in a continuous batch mode; anddirectly contacting the additional vapor with the pH adjusted solution. 24. The method of claim 1, wherein heating the container comprises providing heated air to an exterior of the container at a steady temperature during a transition of a plurality of molecular species from the plastic feedstock into the vapor, wherein each of the plurality of molecular species has a different vaporization temperature at a given pressure. 25. A method of recycling plastic, the method comprising: heating a plastic feedstock under negative pressure so as to effect depolymerization of the plastic feedstock and so as to produce a vapor that comprises a first component and a second component, wherein the first component comprises a gaseous organic species and the second component comprises one or more of an atomic species and a molecular species;directly contacting the vapor with a pH adjusted solution so as to condense the organic species of the first component; andseparating the condensed organic species from the second component. 26. The method of claim 25, wherein at least a portion of the second component of the vapor is in a gaseous state before the vapor is directly contacted with the pH adjusted solution. 27. The method of claim 26, wherein directly contacting the vapor with a pH adjusted solution condenses at least a portion of the second component. 28. The method of claim 25, wherein the second component of the vapor comprises one or more of a metal species, a polar organic species, an organic acid species, and inorganic acid species. 29. The method of claim 25, wherein the organic species of the first component of the vapor comprises one or more species of non-polar organic molecules. 30. The method of claim 25, wherein directly contacting the vapor with the pH adjusted solution causes absorption of at least a portion of the second component into the solution, wherein the condensed organic species of the first component is less dense than water and is hydrophobic, and wherein separating the condensed organic species from the second component comprises retaining the condensed organic species and the pH adjusted solution into which at least a portion of the second component has been absorbed in a common reservoir. 31. The method of claim 30, wherein separating the condensed organic species from the second component further comprises permitting at least a portion of the condensed organic species to flow over an upper edge of the reservoir while retaining the pH adjusted solution into which at least a portion of the second component has been absorbed within a separate region of the reservoir. 32. The method of claim 25, wherein said directly contacting the vapor with a pH adjusted solution comprises bubbling the vapor through the pH adjusted solution. 33. The method of claim 25, wherein said directly contacting the vapor with a pH adjusted solution comprises spraying the vapor with the pH adjusted solution. 34. The method of claim 33, wherein directly contacting the vapor with the pH adjusted solution causes absorption of at least a portion of the second component into the solution, wherein the condensed organic species is less dense than water and is hydrophobic, and wherein separating the condensed organic species from the second component comprises retaining the condensed organic species and the pH adjusted solution into which at least a portion of the second component has been absorbed in a common reservoir, the method further comprising spraying additional vapor obtained from the plastic feedstock with the pH adjusted solution into which the second species has been absorbed. 35. A method of recycling plastic, the method comprising: heating a plastic feedstock under negative pressure so as to effect depolymerization of the plastic feedstock and so as to produce a vapor that comprises a first component and a second component, wherein the first component comprises a gaseous organic species and the second component comprises one or more of an atomic species and a molecular species;directly contacting the vapor with a pH adjusted solution at a first temperature so as to absorb at least a portion of the second component of the vapor; andcondensing the first component of the vapor. 36. The method of claim 35, further comprising separating the condensed organic species from the second component after having condensed the first component of the vapor. 37. The method of claim 35, wherein the condensed first component of the vapor and a portion of the pH adjusted solution into which at least a portion of the second component of the vapor has been absorbed are included together in an emulsion; the method further comprising separating the condensed organic species from the pH adjusted solution. 38. The method of claim 35, wherein condensing the first component of the vapor comprises directly contacting the first component of the vapor with a pH adjusted solution that is at a second temperature, wherein the first temperature is higher than the second temperature. 39. The method of claim 38, wherein a composition of the pH adjusted solution that is used to absorb at least a portion of the second component of the vapor and a composition of the pH adjusted solution that is used to condense the first component of the vapor are the same. 40. The method of claim 35, wherein directly contacting the vapor with a pH adjusted solution comprises spraying the vapor. 41. A method of recycling plastic, the method comprising: heating a plastic feedstock under negative pressure so as to effect depolymerization of the plastic feedstock and so as to produce a vapor that comprises a first component and a second component, wherein the first component comprises a gaseous organic species and the second component comprises one or more of an atomic species and a molecular species;directly contacting the vapor with a pH adjusted solution at a first temperature so as to absorb at least a portion of the second component of the vapor; anddirectly contacting the vapor with a condensing liquid at a second temperature so as to condense the first component of the vapor. 42. The method of claim 41, wherein a composition of the pH adjusted solution and a composition of the condensing liquid are the same. 43. The method of claim 41, wherein the condensed first component of the vapor and the condensing liquid are included together in an emulsion; the method further comprising separating the condensed organic species from the condensing liquid. 44. A method of recycling plastic, the method comprising: introducing a first cartridge that contains a first quantity of plastic feedstock into a first heating plenum;introducing a second cartridge that contains a second quantity of plastic feedstock into a second heating plenum;heating both the first and second cartridges such that the first quantity of plastic feedstock yields a first vapor and the second quantity of plastic feedstock yields a second vapor;introducing the first and second vapors into a vapor treatment system; andsimultaneously contacting the first and second vapors with a pH adjusted solution. 45. The method of claim 44, further comprising combining at least a portion of the first and second vapors within a gas transfer line prior to introducing the first and second vapors into the vapor treatment system. 46. The method of claim 44, wherein heating both the first and second cartridges comprises providing heated fluid to the first heating plenum from a first burner and providing heated fluid to the second heating plenum from a second burner that is independent of the first burner. 47. The method of claim 46, further comprising: removing the first cartridge from the first heating plenum;introducing a third cartridge that contains a third quantity of plastic feedstock into the first heating plenum; andheating the third cartridge such that the third quantity of plastic feedstock yields a third vapor. 48. The method of claim 47, further comprising combining at least a portion of the third vapor and at least a portion of the second vapor within a gas transfer line; and introducing the combined portions of the third and second vapors into the vapor treatment system. 49. The method of claim 47, further comprising maintaining operation of the second burner so as to heat the second container while removing the first cartridge from the first heating plenum and while introducing the third cartridge into the first heating plenum. 50. The method of claim 44, wherein contacting the first and second vapors with a pH adjusted solution takes place after the first and second vapors have been introduced into the vapor treatment system. 51. A plastic recycling system comprising: a sealable container having a plastic feedstock therein, the container comprising a port;a heating system configured to receive the container and to apply heat thereto in an amount sufficient to result in depolymerization of the plastic feedstock;a gas transfer system coupled with the port of the container so as to remove vapor from the container through the port and into the gas transfer system; anda vapor treatment system in fluid communication with the gas transfer system, the vapor treatment system comprising a pH adjusted solution, wherein the vapor treatment system is configured to effect direct contact between the pH adjusted solution and vapor that is received into the vapor treatment system from the gas transfer system and is configured to condense an organic molecular species from the vapor. 52. The system of claim 51, wherein the vapor treatment system further comprises a reservoir that contains at least a portion of the pH adjusted solution, wherein the reservoir is configured to receive the condensed organic molecular species. 53. The system of claim 52, wherein the reservoir comprises a weir such that at least a portion of the condensed organic molecular species can flow over an edge of the weir so as to be separated from the pH adjusted solution. 54. The system of claim 51, wherein the vapor treatment system comprises a first sprayer that is configured to spray the vapor with the pH adjusted solution at a first temperature. 55. The system of claim 54, wherein the vapor treatment system further comprises a second sprayer that is configured to spray the vapor with the pH adjusted solution at a second temperature, wherein the first temperature is higher than the second temperature. 56. The system of claim 55, wherein the first sprayer is positioned lower than the second sprayer such that a portion of the vapor rises toward the second sprayer after having been sprayed by the first sprayer. 57. The system of claim 51, further comprising a cooling system configured to maintain the pH adjusted solution that is used for direct contact with the vapor at a temperature lower than that of the vapor. 58. The system of claim 51, further comprising a vacuum system that is in fluid communication with the container when the container is sealed and is configured to maintain negative pressure within the container during heating thereof. 59. The system of claim 58, wherein the vacuum system is in fluid communication with the vapor treatment system and the gas transfer system and is configured to maintain negative pressure within the vapor treatment system and the gas transfer system during operation of the plastic recycling system. 60. The system of claim 51, further comprising: a control system; andone or more of a temperature sensor and a pressure sensor in communication with the control system and positioned to obtain measurements of the vapor,wherein the control system is configured to adjust or terminate an amount of heat delivered to the container by the heating system in response to the measurements. 61. The system of claim 51, further comprising a settling tank and a pump that is in fluid communication with the vapor treatment system, wherein the pump is configured to transport at least a portion of the condensed organic molecular species to the settling tank. 62. The system of claim 51, further comprising an environmental control device, wherein non-condensable components of the vapor are delivered from the condenser system to the environmental control device. 63. The system of claim 62, wherein the environmental control device provides heated exhaust to a portion of the heating system. 64. A plastic recycling system comprising: a sealable container having a plastic feedstock therein, the container comprising a port;a heating system configured to receive the container and to apply heat thereto in an amount sufficient to result in depolymerization of the plastic feedstock;a gas transfer system coupled with the port of the container so as to remove vapor from the container through the port and into the gas transfer system;a washing system in fluid communication with the gas transfer system, the washing system comprising a pH adjusted solution, wherein the washing system is configured to effect direct contact between the vapor and the pH adjusted solution so as to absorb impurities from the vapor; anda vapor treatment system configured to receive a portion of the vapor from the washing system, wherein the vapor treatment system is configured to condense an organic molecular species from the vapor. 65. A system for recycling plastic, the system comprising: a sealable container configured to receive a plastic feedstock therein, the container comprising a vacuum port;a plenum sized to receive at least a portion of the container therein;a burner in fluid communication with the plenum, wherein the burner is configured to apply heat to the container when the container is received within the plenum so as to convert at least a portion of the plastic feedstock into a vapor;a vapor treatment system that comprises a pH adjusted solution; anda vacuum system in fluid communication with the vacuum port of the container,wherein the vacuum system is configured to maintain a vacuum within the container during heating of the container and is further configured to remove the vapor from the container and introduce the vapor into the vapor treatment system, and wherein the vapor treatment system is configured to directly contact the vapor with the pH adjusted solution so as to separate constituent components of the vapor from each other.