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A process comprising contacting a liquid polyester stream with hydrogen in the presence of a hydrogenation catalyst comprising a metal supported on the surface of silicon carbide at a metal dispersion of at least 0.5% or graphite at a metal dispersion of at least 10% to produce a treated liquid poly

A process comprising contacting a liquid polyester stream with hydrogen in the presence of a hydrogenation catalyst comprising a metal supported on the surface of silicon carbide at a metal dispersion of at least 0.5% or graphite at a metal dispersion of at least 10% to produce a treated liquid polyester stream. The treated stream may be polycondensed in the presence of a polycondensation catalyst to produce a polyester polymer having an It.V. of at least 0.55 dL/g. The liquid polyester stream desirably has a composition comprising: a) terephthalic acid residues, isophthalic acid residues, and/or naphthalenedicarboxylic acid residues and b) an average degree of polymerization of 0.5 to 20 and c) an acid number ranging from 5 to 600.

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We claim: 1. A melt phase process for the manufacture of a polyester polymer comprising: (1) in the melt phase process for producing a polyester polymer, contacting a liquid polyester stream, having an average decree of polymerization of 0.5 to 20, with hydrogen in the presence of a hydrogenation c

We claim: 1. A melt phase process for the manufacture of a polyester polymer comprising: (1) in the melt phase process for producing a polyester polymer, contacting a liquid polyester stream, having an average decree of polymerization of 0.5 to 20, with hydrogen in the presence of a hydrogenation catalyst comprising a metal supported on the surface of silicon carbide at a metal dispersion of at least 0.5% or graphite at a metal dispersion of at least 10% to produce a treated liquid polyester stream; (2) and polycondensing the treated oligomer stream to produce said polyester polymer. 2. The process of claim 1, wherein the liquid polyester stream, comprising an oligomeric stream, is contacted with hydrogen in the presence of the hydrogenation catalyst at a temperature of 150 to 300째 C. under a pressure ranging from about 20 psig to 300 psig, a hydrogen gas hourly space velocity of 6 to 1000, and an oligomer stream liquid hourly space velocity ranging from 0.2 to 40. 3. The process of claim 2, wherein the temperature is in a range of 240째 C. to 280째 C., the liquid hourly space velocity ranges from 1 to 15, and a gas hourly space velocity ranges from 100 to 400. 4. The process of claim 1, wherein the metal is selected from the group consisting of ruthenium, rhodium, palladium, platinum, osmium and nickel. 5. The process of claim 4, wherein the metal is selected from the group consisting of palladium, platinum and nickel. 6. The process of claim 1, wherein the average pore diameter of the support is within a range of 0.8 to 40 nm. 7. The process of claim 6, wherein the pore volume is within a range of 0.1 to 0.8 cc/g. 8. The process of claim 6, wherein the metal dispersion is at least 15% on graphite or at least about 1% on silicon carbide. 9. The process of claim 1, wherein the metal dispersion is at least 15% on graphite or at least about 1% on silicon carbide. 10. The process of claim 1, wherein the hydrogenation catalyst is in the form of pellets having an average diameter within a range of 1/16" to ⅜". 11. The process of claim 1, wherein the metal dispersion is at least 15% on graphite or at least 1% on silicon carbide and the amount of metal loaded on the silicon carbide support ranges from 0.1 wt. % to 5 wt. %. 12. The process of claim 1, wherein the treated liquid polyester stream has a b* color value reduced by 3 or more units relative to the b* value of the liquid polyester stream. 13. The process of claim 1, wherein the b* color value of the treated polyester stream is reduced by at least 50% relative to the b* color value of the liquid polyester stream. 14. The process of claim 1, wherein the b* value of the liquid polyester stream is 5 or more and the final b* value of the treated liquid polyester stream is less than 2.5. 15. The process of claim 1, wherein the average DP of the liquid polyester stream ranges from 1.5 to less than 7. 16. The process of claim 1, wherein the average DP of the liquid polyester stream ranges from 7 to 20. 17. The process of claim 1, wherein the liquid polyester stream comprises post consumer recycled polyester polymer. 18. The process of claim 17, wherein the It.V. of the liquid Polyester stream is 0.45 dL/g or less. 19. The process of claim 1, wherein the liquid polyester composition comprises: a) terephthalic acid residues, isophthalic acid residues, and/or naphthalenedicarboxylic acid residues and b) having an average degree of polymerization of 0.5 to 20 and c) having an acid number ranging from 5 to 600. 20. The process of claim 19, wherein the liquid polyester composition comprises terephthalic acid residues, has an average degree of polymerization in a range of 1.5 to less than 7, and has an acid number in a range of 100 to 300. 21. The process of claim 1, wherein the liquid polyester polymer flows through a bed of the hydrogenation catalyst. 22. The process of claim 1, wherein the liquid polyester stream has a composition comprising an oligomer represented by the formula: description="In-line Formulae" end="lead"HO--[Diol] x[--TPA--Diol--]y--Hdescription="In-line Formulae" end="tail" wherein Diol is a divalent residue of a diol component, TPA is the divalent residue of terephthalic acid, x is 0 or 1, and y has an average value of about 1.5 to less than 7. 23. The process according to claim 22 wherein Diol comprises a divalent residue of ethylene glycol and at least 1 mole percent of the terephthalic acid residues are converted to 1,4-cyclohexanedicarboxylic acid residues. 24. The process of any one of claims 1-23, wherein the support comprises silicon carbide, and the polyester polymer comprises residues of terephthalic acid. 25. The process of any one of claims 1-23, wherein the support comprises graphite, and the polyester polymer comprises residues of terephthalic acid. 26. The process of any one of claims 1-23, further comprising: (1) the liquid polyester stream comprises an oligomer stream having an average degree of polymerization in the range of 1.5 to less than 7, and (2) polycondensing the treated oligomer stream in the presence of a polycondensation catalyst to produce a polyester polymer having an It.V. of at least 0.55 dL/g. 27. The process of claim 26, wherein the support comprises silicon carbide. 28. The process of claim 26, wherein the support comprises graphite. 29. The process of claim 26, wherein the polyester polymer comprises: (i) diacid residues comprising 1,4-cyclohexanedicarboxylic acid residues and at least 80 mole % terephthalic acid residues based on all moles of acid residues; and (ii) diol residues comprising at least 80 mole % ethylene glycol residues based on all the moles of polyfunctional hydroxyl compound residues. 30. The process of claim 27, wherein the polyester polymer is further processed is molded into a bottle preform. 31. The process of claim 1, wherein the liquid polyester stream is esterified to a degree of esterification of at least 70% prior to contact with the hydrogen in the presence of a hydrogenation catalyst.