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A system employing a regenerable zinc-oxide based sorbent to remove one or more contaminants from an incoming gas stream. The contaminant-depleted gas stream can then be used for any subsequent application, while at least a portion of the contaminant-laden sorbent can be regenerated via a step-wise

A system employing a regenerable zinc-oxide based sorbent to remove one or more contaminants from an incoming gas stream. The contaminant-depleted gas stream can then be used for any subsequent application, while at least a portion of the contaminant-laden sorbent can be regenerated via a step-wise regeneration process. In one embodiment, sorbent regenerated via the step-wise regeneration process can comprise less sorbent-damaging compounds than traditional sorbents exposed to conventional regeneration processes.

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What is claimed is: 1. A process comprising: (a) contacting an sulfur-containing gas stream with an initial sorbent in a sorption zone to thereby produce an sulfur-depleted product stream and a sulfur-laden sorbent, wherein said initial sorbent comprises Zn and a promoter metal; and (b) contacting

What is claimed is: 1. A process comprising: (a) contacting an sulfur-containing gas stream with an initial sorbent in a sorption zone to thereby produce an sulfur-depleted product stream and a sulfur-laden sorbent, wherein said initial sorbent comprises Zn and a promoter metal; and (b) contacting at least a portion of said sulfur-laden sorbent with a regeneration gas stream in a regeneration zone under regeneration conditions to thereby produce a regenerated sorbent and an off-gas stream, wherein said contacting of step (b) includes introducing said regeneration gas into said regeneration zone at an initial standard gas hourly space velocity (SGHSV) in the range of from about 100 to about 100,000 h−1, wherein said contacting of step (b) includes increasing the SGHSV of said regeneration gas to a final SGHSV that is at least 1,000 h−1 higher than said initial SGHSV. 2. The process of claim 1, wherein said contacting of step (b) further comprises increasing the temperature of said regeneration zone by at least 75° C. 3. The process of claim 2, wherein said contacting of step (b) further comprises alternating said increasing the temperature of said regeneration zone and said increasing the SGHSV of said regeneration gas, wherein said alternating is carried out until said off-gas stream comprises less than about 0.05 volume percent sulfur dioxide (SO2). 4. The process of claim 1, wherein said contacting of step (b) is carried out at a temperature less than 650° C. for a period of time less than 24 hours. 5. The process of claim 1, wherein said sulfur-laden sorbent has a sulfur loading in the range of from about 1 to about 27 weight percent, wherein said regenerated sorbent has a sulfur loading of less than 10 weight percent. 6. The process of claim 1, wherein said promoter metal is nickel. 7. The process of claim 1, wherein said initial sorbent comprises a substitutional solid metal solution characterized by the formula MAZnB, wherein M is said promoter metal, wherein A and B are in the range of from about 0.01 to about 0.99. 8. The process of claim 1, further comprising, prior to step (b), drying at least a portion of said sulfur-laden sorbent to thereby provide a dried sulfur-laden sorbent and subjecting at least a portion of said dried sulfur-laden sorbent to said contacting of step (b). 9. The process of claim 8, wherein said sulfur-containing gas stream comprises in the range of from about 4 to about 40 volume percent water, wherein said regenerated sorbent comprises in the range of from 0 to about 10 weight percent of sorbent-damaging compounds created during said contacting of step (b). 10. The process of claim 9, wherein said sulfur-containing gas stream further comprises in the range of from about 10 to about 75 volume percent carbon monoxide (CO) and in the range of from about 8 to about 50 volume percent hydrogen (H2). 11. The process of claim 1, wherein said sulfur-containing gas stream comprises in the range of from about 0.001 to about 5 volume percent H2S, wherein said sulfur-depleted product stream comprises less than 50 ppmv H2S. 12. The process of claim 1, further comprising introducing at least a portion of said regenerated sorbent into said sorption zone, wherein said regenerated sorbent introduced into said sorption zone comprises a substitutional solid metal oxide solution characterized by the formula MXZnYO, wherein M is said promoter metal, wherein X and Y are in the range of from about 0.01 to about 0.99. 13. A process comprising: (a) introducing a raw gas stream into a sorption zone, wherein said raw gas stream comprises in the range of from about 10 to about 75 volume percent carbon monoxide (CO), in the range of from about 8 to about 50 volume percent hydrogen (H2), in the range of from about 4 to about 40 volume percent water (H2O), and in the range of from about 0.001 to about 5 volume percent hydrogen sulfide (H2S); (b) contacting at least a portion of said raw gas stream with an initial sorbent in said sorption zone to thereby produce a product gas stream and a sulfur-laden sorbent, wherein said initial sorbent comprises Zn and a promoter metal; (c) drying at least a portion of said sulfur-laden sorbent to thereby produce a dried sulfur-laden sorbent; and (d) regenerating at least a portion of said dried sulfur-laden sorbent in a regeneration zone under regeneration conditions to thereby produce a regenerated sorbent and an off-gas stream, wherein said regenerated sorbent comprises less than about 20 weight percent of sorbent-damaging compounds formed during said regenerating of step (d). 14. The process of claim 13, wherein said sulfur-laden sorbent comprises in the range of from about 10 to about 20 weight percent sorbed sulfur, wherein said regenerating of step (d) removes at least 90 weight percent of said sorbed sulfur. 15. The process of claim 13, wherein said sorbent-damaging compounds include zinc oxysulfate and/or zinc silicate. 16. The process of claim 13, wherein said regenerating of step (d) is carried out with an initial temperature in the range of from about 250 to about 650° C., wherein said regenerating of step (d) further comprises increasing the temperature of said regeneration zone by at least 75° C. above said initial temperature during a time period of less than about 24 hours. 17. The process of claim 13, wherein said regenerating of step (d) includes introducing a regeneration gas having an initial standard hourly space velocity (SGHSV) greater than 1,000 h−1 into said regeneration zone, wherein said regenerating of step (d) includes increasing the SGHSV of said regeneration gas by at least about 1,000 h−1. 18. The process of claim 13, wherein said raw gas stream further comprises in the range of from about 100 to about 5,000 parts per million by volume (ppmv) of carbonyl sulfide (COS) and in the range of from about 50 to about 2,000 ppmv of hydrochloric acid (HCl), wherein said product gas stream comprises less than 20 ppmv of said HCl and/or said COS. 19. The process of claim 13, wherein said product gas comprises less than 50 ppmv of H2S. 20. The process of claim 13, wherein said initial sorbent comprises a substitutional solid metal solution characterized by the formula MAZnB, wherein M is said promoter metal, wherein A and B are in the range of from about 0.01 to about 0.99, wherein said promoter metal is nickel. 21. The process of claim 13, further comprising introducing at least a portion of said regenerated sorbent into said sorption zone, wherein said regenerated sorbent introduced into said sorption zone comprises a substitutional solid metal oxide solution characterized by the formula MXZnYO, wherein M is said promoter metal, wherein X and Y are in the range of from about 0.01 to about 0.99. 22. A process comprising: (a) gasifying a carbon-containing material in a gasification zone to thereby produce a raw gas stream, wherein said raw gas stream comprises in the range of from about 10 to about 75 volume percent carbon monoxide (CO), in the range of from about 8 to about 50 volume percent hydrogen (H2), in the range of from about 4 to about 40 volume percent water (H2O), in the range of from about 0.001 to about 5 volume percent sulfur-containing compounds, and in the range of from about 50 to about 2,000 parts per million by volume (ppmv) of hydrochloric acid (HCl); (b) introducing at least a portion of said raw gas stream into a sorption zone, wherein said sorption zone contains an initial sorbent, wherein said initial sorbent comprises Zn, expanded perlite, and a promoter metal, wherein at least a portion of said initial sorbent comprises a substitutional solid solution characterized by the formula MZZn(1-Z)Al2O4 and a substitutional solid metal solution characterized by the formula MAZnB, wherein M is a promoter metal component and A, B, and Z are in the range of from about 0.01 to about 0.99; (c) sorbing at least a portion of said sulfur-containing compounds from said raw gas stream in said sorption zone with said initial sorbent to thereby produce a sulfur-laden sorbent and a product gas stream, wherein said sorbing is carried out at a temperature in the range of from about 225 to about 550° C. and a pressure in the range of from about 250 to about 575 psig, wherein said sulfur-laden sorbent has a sulfur loading in the range of from about 1 to about 27 weight percent, wherein said product gas stream comprises less than 50 ppmv of sulfur-containing materials and less than 20 ppmv of HCl; (d) drying at least a portion of said sulfur-laden sorbent in a drying zone to thereby produce a dried sulfur-laden sorbent; (e) regenerating at least a portion of said dried sulfur-laden sorbent in a regeneration zone via contact with a regeneration gas under regeneration conditions to thereby produce a regenerated sorbent and a SO2-containing off-gas, wherein said regeneration gas has an initial standard gas hourly space velocity (SGHSV) in the range of from about 1,000 to about 80,000 h−1, wherein said regenerating is carried out with an initial temperature in the range of from about 300 to about 600° C.; (f) returning at least a portion of said regenerated sorbent to said sorption zone, wherein said regenerated sorbent returned to said sorption zone comprises a substitutional solid metal oxide solution characterized by the formula MXZnYO, wherein M is a promoter metal component and X and Y are in the range of from about 0.01 to about 0.99, wherein said regenerated sorbent has a sulfur loading of less than 6 weight percent, wherein said regenerated sorbent comprises less than 20 weight percent of sorbent-damaging compounds created during said regenerating of step (e); and (g) routing at least a portion of said SO2-containing off-gas stream to a Claus unit. 23. The process of claim 22, wherein said regenerating of step (e) further comprises alternating between the sub-steps of: (e1) increasing the temperature of said regeneration zone by a first incremental amount, wherein the magnitude of said first incremental amount is in the range of from 10 to 30 percent of said initial temperature; and (e2) increasing the SGHSV of said regeneration gas by a second incremental amount, wherein the magnitude of said second incremental amount is in the range of from 10 to 30 percent of said initial SGHSV, wherein steps (e1) and (e2) are carried out over a time period of less than 12.5 hours, wherein said alternating between steps (e1) and (e2) is carried out until said off-gas stream comprises less than about 500 ppmv of sulfur dioxide. 24. The process of claim 22, wherein said promoter metal is nickel. 25. The process of claim 22, wherein the temperature of said sorption zone is within at least 200° C. of the temperature of said raw gas stream exiting said gasification zone.