US 2026/0217627 A1 · Chemocatalytic Conversion of Polyaddition Polymers in Low-Value Feedstocks to Higher-Value Hydrocarbons

Abstract

Methods, systems, catalysts, and products are disclosed for converting polyaddition polymers (PAP) contained in low-value feedstocks into lower-molecular-weight hydrocarbons of higher value. In representative embodiments, a PAP-containing feedstock is combined with a first process agent comprising a mineral-based catalyst and heated under elevated temperature and pressure to promote selective carbon-carbon bond scission and formation of reactive fragments. In the presence of water, hydrogen equivalents are generated autogenously in situ by aqueous reforming of at least a portion of the reactive fragments and are used to quench other fragments, thereby forming stabilized hydrocarbon products. Conversion proceeds through iterative scission and quenching without reliance on thermolytic cracking, externally supplied hydrogen, or post-conversion hydrotreating. The methods are applicable to mixed and contaminated feedstocks comprising polyolefins, polystyrene, polyisobutylene, and tire rubber, and tolerate heteroatom-containing contaminants. The resulting products comprise substantially saturated hydrocarbons suitable for use as fuels, solvents, lubricant basestocks, or chemical feedstocks.

Claims41

Dependent claims

A method for converting a feedstock comprising one or more polyaddition polymers (PAP) into lower-molecular-weight hydrocarbons, the method comprising:

(a) combining the feedstock with a first process agent (PA1) comprising one or more mineral-based catalysts to obtain an initial reaction mixture;
(b) heating the initial mixture to an initial conversion temperature T(init) in a range of about 390° C. to about 440° C. while dispersing PA1 to promote carbon-carbon bond scission in the PAP and to form reactive fragments F;
(c) in the presence of water in an amount sufficient to support in situ aqueous reforming (AR), generating hydrogen equivalents H(equiv) autogenously from at least a portion of the reactive fragments F;
(d) quenching at least a portion of other reactive fragments F with the H(equiv) to form stabilized fragments F-H;
(e) heating the initial mixture, with additional water as required, to a main conversion temperature T(main) in a range of about 390° C. to about 430° C. under a pressure of 200 to 1500 psi to promote iterative scission and quenching, thereby forming progressively smaller stabilized fragments F-H;
and
(f) recovering from the reaction mixture a product mixture comprising lower-molecular-weight hydrocarbons that have an average carbon number of about C6 to C35 and are substantially saturated.

4 more elements

Dependencies are inferred from the claim text.

Chemocatalytic Conversion of Polyaddition Polymers in Low-Value Feedstocks to Higher-Value Hydrocarbons

Life of this patent

Chemocatalytic Conversion of Polyaddition Polymers in Low-Value Feedstocks to Higher-Value Hydrocarbons

Life of this patent

Abstract

Claims41