Processes for electrochemical up-cycling of plastics and systems thereof

Abstract

Methods and systems for the electrochemical up-cycling of polymers. A slurry including a mixture of solid plastics flows through an electrochemical cell, which, through an applied potential, the plastics are converted into pure hydrogen, fuels, gasolines, and oxygen hydrogenated compounds that can be used for the synthesis of advanced materials and/or for easier biochemical/thermal degradation. Such methods and systems enables converting plastic waste to into fuels, chemicals, and high value products.

1 . A method for electrochemical up-cycling of polymers, wherein the method comprises:
 (a) preparing a slurry comprising a mixture of plastic particles;   (b) flowing the slurry into an electrochemical cell, wherein
 (i) the electrochemical cell comprises (A) a cathode in a cathode compartment and (B) an anode in an anode compartment, and 
 (ii) the slurry is flown through the anode compartment; 
   (c) providing a medium selected from a group consisting of
 (i) an electrolyte, wherein
 (A) the electrolyte is flowable though the cathode of the electrochemical cell, and 
 (B) the electrochemical cell further comprises a membrane or separator between the anode and the cathode; and 
 
 (ii) protons that can be pumped from decomposition of the plastic particles in the slurry from the anode and reduced at the cathode; 
   (d) providing a voltage or current between the anode and the cathode of the electrochemical cell; and   (e) oxidizing the plastic particles in the slurry to prepare a product selected from a group consisting of fuels, chemicals, oxy-hydrogenated products, and combinations thereof.   
     
     
         2 . The method of  claim 1 , wherein the product is selected from a group consisting of pure hydrogen, gasolines, monomers, and combinations thereof. 
     
     
         3 . The method of  claim 1 , wherein the product is an oxygen hydrogenated compound that can be used for at least of one the synthesis of materials and biochemical/thermal degradation. 
     
     
         4 . The method of  claim 1 , wherein the slurry is a mixture of plastics and polymers. 
     
     
         5 . The method of  claim 1 , wherein the slurry is formed by grinding plastics. 
     
     
         6 . The method of  claim 5 , wherein the slurry further comprises the electrolyte. 
     
     
         7 . The method of  claim 1 , wherein particle size of the plastic particles is in a range of about 10 microns and about 2000 microns. 
     
     
         8 . The method of  claim 1 , wherein the anode comprises a conductive material support selected from a group consisting of Ni gauze/mesh, Ti, stainless steel, Ni—Cr—MO alloys, graphite, nickel foam, Ti foam, aluminum, aluminum foam, and combinations thereof. 
     
     
         9 . The method of  claim 1 , wherein the anode comprises a conductive material support selected from a group consisting of carbon, carbon fibers, and graphene. 
     
     
         10 . The method of  claim 1 , wherein the anode comprises a catalyst comprising a metal selected from a group consisting of Ni, Fe, Co, Cr, Mo, Pt, Rh, Ru, Pd, Ir, and combinations thereof, and composites of graphene metal combinations. 
     
     
         11 . The method of  claim 10 , wherein loading of the catalyst is in a range between 0.1 mg/cm 2  and 2 mg/cm 2 . 
     
     
         12 . The method of  claim 1 , wherein the anode comprises a catalyst comprising carbon material selected from a group consisting of carbon fibers, carbon paper, carbon cloth, graphene, and carbon nanotubes. 
     
     
         13 . The method of  claim 1 , wherein the anode is a carbon fiber electrode comprising a Pt electrocatalyst. 
     
     
         14 . The method of  claim 1 , wherein the anode is a Ni mesh electrode. 
     
     
         15 . The method of  claim 1 , wherein the cathode comprises a conductive material support selected from a group consisting of Ni gauze/mesh, Ti, stainless steel, Ni—Cr—MO alloys, graphite, nickel foam, Ti foam, aluminum, aluminum foam, and combination thereof. 
     
     
         16 . The method of  claim 1 , wherein the cathode comprises a conductive material support selected from a group consisting of carbon, carbon fibers, carbon paper, carbon cloth, and graphene. 
     
     
         17 . The method of  claim 1 , wherein the cathode comprises an electrocatalyst comprising a material selected from a group consisting of carbon, graphene, Ni, Fe, Co, Mo, Pt, Rh, Ru, Pd, Ir, and combinations thereof. 
     
     
         18 . The method of  claim 1 , wherein the electrochemical cell comprises the electrolyte. 
     
     
         19 . The method of  claim 18 , wherein the electrochemical cell comprises the membrane. 
     
     
         20 . The method of  claim 19 , wherein the membrane comprises nafion or fritted glass. 
     
     
         21 . The method of  claim 18 , wherein the electrochemical cell comprises the separator. 
     
     
         22 . The method of  claim 21 , wherein the separator comprises polyethylene. 
     
     
         23 . The method of  claim 18 , wherein the electrolyte comprises an acid. 
     
     
         24 . The method of  claim 23 , wherein the acid is sulfuric acid or phosphoric acid. 
     
     
         25 . The method of  claim 23 , wherein the acid is at a concentration in a range of 0.1 M and 9 M. 
     
     
         26 . The method of  claim 18 , wherein the electrolyte comprises a catalytic additive. 
     
     
         27 . The method of  claim 26 , wherein the catalytic additive comprises an additive selected from a group consisting of Fe +2 , Fe +3 , Cr +2 , Cr +3 , V +3 , V +2 , and salts thereof. 
     
     
         28 . The method of  claim 26 , wherein the catalytic additive is at a concentration in a range of 10 mM and 1000 mM. 
     
     
         29 . The method of  claim 1 , wherein the electrochemical cell comprises an additive. 
     
     
         30 . The method of  claim 1 , wherein the electrochemical cell further comprises a reference electrode. 
     
     
         31 . The method of  claim 30 , wherein the reference electrode comprises a material selected from a group consisting of Pt, Ni, Au, Ag/AgCl, Ag, and combinations thereof. 
     
     
         32 . The method of  claim 1 , wherein the step of oxidizing the plastic particles occurs while controlling temperature in a range between 20° C. and 180° C. 
     
     
         33 - 90 . (canceled)