MXPA01000311A - Process and catalyst/sorber for treating sulfur compound containing effluent - Google Patents

Abstract

A process and composition are provided for removing contaminants, such as sulfur dioxide and hydrogen sulfide, out of exhaust gases by contacting the contaminated exhaust gas with a catalyst/sorber composition comprising noble metal components and a sorber component, such as oxides of Ti, Zr, Hf, Ce, Al, Si and mixtures thereof, so as to remove the contaminants out of the exhaust gas. The contaminant-loaded catalyst/sorber composition is regenerated via contact with a mixture of an inert gas, such as nitrogen, and a reducing gas, such as hydrocarbons. The catalyst/sorber composition may also contain a modifier, such as Cu, Ag or Bi, which tends to promote the release of the sulfur contaminant off the contaminant-loaded catalyst/sorber composition as sulfur dioxide, rather than the hydrogen sulfide. The catalyst/sorber composition also promotes the oxidation of carbon monoxide in the exhaust gas.

Description

PROCESS AND CATALYZER / SORBENT TO TREAT AN SULFUR COMPOUND CONTAINING EFFLUENT DESCRIPTION OF THE INVENTION The present invention relates to the elimination of gaseous sulfur compounds from gaseous streams, particularly the removal of S02 and H2S from combustion and industrial process effluents, using a regenerable / sorbent catalyst. As a result of concern with air pollution, environmental regulators have severely reduced and are continuous to reduce allowable emissions of sulfur oxides and hydrogen sulfide. As a result, a variety of technologies have been developed and are continuing to be developed for use in boiler tube gas desulfurization (FGD). FGD techniques can generally be classified as wet and dry scrubbing. Dry scrubbing contacts the effluent with a solid material which chemically reacts with a sulfur component and forms a compound. The system can be a fixed bed such as zinc oxide pellets which are used to react with H2S to form zinc sulphide. Zinc sulfide pellets can be removed and replaced after saturation. The dry scrubbing may also be powder or particulate material injected into the stream followed by a powder precipitate or electrostatic filtration to remove the reactive product. An example of a powder could be limestone, which can react after injection in the exhaust stream to form calcium sulfate and / or calcium sulfite hemihydrate sludge. The material is typically supplied as a wet suspension, which dries in the vacuum cleaner and reacts with the sulfur oxides. This material is then removed and typically disposed within a burial. There are also regenerable dry scouring materials such as copper oxide in pellets or aluminum oxide spheres. Regenerable copper systems can be heated to, and reduced to, high temperatures. This technique requires that the sorption temperature be lower than the regeneration temperature. Scouring techniques use wet suspensions or amine solutions and require that the exhaust temperature be reduced below the boiling point of the solutions to be used. These techniques give rise to losses by evaporation and shipping and produce products which are contaminated and unusable and can be disposed of / or purified before reuse. The present invention introduces a new technology for the elimination of H2S, S02 and oxidation of CO. This technology uses a catalytic oxidation sorption process for the elimination of the sulfur component where the sulfur component is first oxidized and pre-concentrated and then released into a much smaller concentrated volume stream, which is supplied for processes to recover as sulfur, sulfur dioxide, or sulfuric acid. This technology has tremendous advantages over scrubbing techniques. It is an advantage that the present process operates in the exhaust stream with oxidative capture mode and reductive regeneration that occurs at the same temperature. It is a further advantage that this is a drying process, which is selective for sulfur components and will produce sulfur oxide outside the gases with high concentration and purity. It is a feature of the present invention that it reduces the volume of sulfur containing gases thereby reducing the costs for further processing. It is an additional feature that the process also operates over a wide range of temperatures 93.333 ° C to 426 ° C (200 ° F to 800 ° F). It is another advantage of the process of the present invention that it has high capture efficiencies of over 99.75% and also has very low drop pressure. One aspect of the present invention is a process for the removal of gaseous sulfur compounds, particularly S02 and / or H2S from gaseous streams, such as effluent combustion and industrial process streams, comprising contacting a gaseous stream, containing gaseous sulfur compounds with a catalyst / sorbent under sulfur sorbent condition, such a catalyst / sorbent comprising a noble metal catalyst component, a metal oxide sorbent component, and optionally modifiers consisting of oxides of Ag, Cu, Bi, Sb, Sn, As, In, Pb, Au or mixtures of the same to remove such gaseous sulfur compound from the stream to the catalyst / sorbent. In a preferred embodiment of the present process the gaseous sulfur containing compound is terminated and the sorbed sulfur is desorbed from the catalyst / sorbent by contacting the catalyst / sorbent with a gas stream regeneration under the sulfur compound desorbing conditions whereby the catalyst / sorbent is regenerated by re-use in the sorbent. A more preferred embodiment comprises alternating the steps of sorbing and regeneration. The preferred regeneration gases provide a reduction environment. Reducing agents include hydrogen and hydrocarbons or mixtures thereof. The hydrocarbon is preferably comprised of C? -C? 2 hydrocarbons, which may be used as a compound or mixtures of compounds. Usually the reducing agent will comprise methane and / or a mixture of hydrocarbons. The main source of methane is natural gas. The main component of the gas stream is an inert carrier gas such as nitrogen, helium, argon or steam. The term "main component" is used to measure over 50%. The regeneration can also be carried out with the inert carrier gases alone or with oxygen present. The air can also be used for regeneration. Another aspect of the present invention is the catalyst / sorbent. The noble metal component may comprise Pt, Pd, Rh, Ru or mixtures thereof, preferably Pt. The metal oxide sorbent component is an oxide of Ti, Zr, Hf, Ce, Al, Si or mixtures thereof. In addition to these components the catalyst / sorbent optionally contains a modifier comprising an oxide of Ag, Cu, Bi, Sb, Sn, As In, Pb, Au or mixtures thereof, preferably Cu, Ag, Bi and mixtures thereof. same. The purpose of the modifier is to inhibit the formation of H2S during regeneration. The catalyst / sorbent can be used in the form of pellets, spheres, particulate or extruded material. Preferably, the catalyst / sorbent can be coated within a carrier with a catalyst / sorbent comprising 1 a. 50% of total weight. The noble metal component is preferably present as 0.005 to 20.0% by weight of the catalyst / sorbent, the sorbent component is preferably present starting from 70 to 99% by weight of the catalyst / sorbent, and the modifier is preferably present from 1 at 10% by weight of the catalyst / sorbent. Although the sulfur compounds are removed from gaseous stream in and / or within the catalyst / sorbent according to the present invention, it is not known in what form or by what mechanism the sulfur is associated with the catalyst / sorbent. This is the invention in which the sulfur compounds in the gas stream are in some way liberally associated with the catalyst / sorbent in an oxidizing atmosphere. It is believed that sulfur is associated with the catalyst / sorbent as a compound, more likely as an oxide, but not in the elemental form. Elemental sulfur has not been observed. Preferably, the sulfur is removed from the catalyst / sorbent as a more concentrated stream of sulfur compounds. Unless stated otherwise, the percentages and ratios of the compounds expressed herein are by weight. BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 shows output values S02 during runs of 148.8 ° C (300 ° F) - 30 minutes of sorption with 30 ppm of S02 and the conditions given in Table 2 with different catalyst / sorbent compositions. Figure 2 shows output S02 values during a S02 sorption run of 500 ppm and a S02 sorption run of 60 ppm at 260 ° C (500 ° F). Figure 3 shows sulfur components released during the regeneration of partially saturated Ti02 / Pt catalyst / sorbent. Figure 4 shows the amount of S02 captured and released during a run of 20 minutes and a subsequent reductive regeneration of the Ti02 / Pt catalyst / sorbent at 260 ° C (500 ° F). Figure 5 shows the amount of S02 captured and released during a run of 20 minutes and a subsequent regeneration of the catalyst / sorbent of Ti02 / Pt / Cu at 260 ° C (500 ° F). Figure 6 shows the effect of the Cu loading reported as Cu (N03) 2 precursor in the proportion of H2S and S02 released during 260 ° C (500 ° F) regenerations (Table 4) with the Ti02 / Pt / Cu system . Figure 7 shows sorption operations of S02 from 60 ppm to 148.8 ° C (300 ° F) with catalyst / sorbents of Ti02 / Pt modified with Bi, Ag, or Cu. Figure 8 shows the S02 released during the regeneration of the Ti02 / Pt catalyst / sorbent modified with Bi, Ag, or Cu. Figure 9 shows S02 cycles of 60 ppm consecutive with Ti02 / Cu sorbent / modifier without noble metal catalyst component at 260 ° C (500 ° F).

Figure 10 shows the loading effect of Pt reported as% by weight of sorbent / carrier in the advance of S02 during run cycles of S02 from 600 ppm to 260 ° C (500 ° F). Figure 11 shows the effect of oxygen on the sorption of S02 for the catalyst / sorbent system of Ti02 / Pt. Figure 12 shows capture efficiencies obtained during 75 minutes of 60 PPM sorption cycles with the Ti02 / Pt system at 271.11, 326.66 and 432. 22 ° C (520, 620 and 810 ° F) and comparatively the Ti02 / Pt / Cu system at 326.6 ° C (620 ° F). Figure 13 shows the sorption of H2S with catalytic sorbents of Ti02 / Pt and Ti02 / Pt / Cu with 30 ppm of H2S input at 260 ° C (500 ° F). Figure 14 shows desorption of H2S captured after the sorption run with the Ti02 / Pt system illustrated in Figure 13. Figure 15 shows S02 released during a desorption of 482.22 ° C (900 ° F) with inert gas, which follows an S02 sorption of 100 ppm at 260 ° C (500 ° F). Figure 16 shows sorption operations of S02 of 250 ppm following a standard regeneration and following a thermal regeneration with air. The sorption step can be carried out from 37.77 to 537.77 ° C (100 to 1000 ° F), preferably 148.88 to 315.55 (300 to 600 ° F), to GHSV 200 to 200,000 hours "1 preferably 1,000 to 120,000 hours-1 The pressures may vary from subatmospheric to 500 psig.The sorption step can be carried out from 37.77 to 537.77 ° C (100 to 1000 ° F), preferably 300 to 900 ° F, to GHSV 20 to 20,000 hours-1, preferably 50 to 10,000 hours "1. Pressures may vary from subatmospheric to 500 psig. Upon carrying out the present sorption / desorption the sulfur compounds in the feed can be concentrated from 5 to 100 times. If the carrier is used, the carrier can be characterized as a ceramic or metallic monolith having a honeycomb structure. Preferably, a carrier is used to distribute the catalyst / sorbent and any modifier. The components are deposited within the carrier in the desired proportions. The composition of the ceramic carrier can be any oxide or combination of oxides. Suitable oxide carriers include the oxides of Al, Zr, Ca, Mg, Hf, Ti and various mixtures of the oxides, such as cordierite and mullite. The structure and composition of the carrier is of greater importance. The structure of the carrier affects the flow patterns through the catalyst / sorbent system which in turn affects transport to and from the catalytic surface. The ability of the structure to effectively transport the compounds to be catalyzed to the catalytic surface influences the effectiveness of the catalyst / sorbent. The carrier is preferably macroporous with 64 to 600 cells (pores) per square inch (cpsi) which is approximately 25 to 80 pores per linear inch (ppi), although carriers have 5 to 90 ppi are suitable. The catalyst / sorbent can be conditioned by repeated sorption / desorption cycles. The amount of sulfur component released during these increments conditioned with each regeneration up to this equals the amount sorbed. It has been found that to pre-treat the catalyst / sorbent with dilute H2SO4, that the conditioning time was dramatically reduced. For example, instead of 12 hours, conditioning after H2S0 treatment only requires several hours at 148.8 ° C (300 ° F). The conditioning time was also found to be dependent on the temperature at which the sorption and regenerations were directed. By increasing the temperature one can increase the amount released, therefore, decreasing the conditioning time a special conditioning may not be necessary, since the catalyst / sorbent will be conditioned after several cycles of sorption / regeneration and remains so after that . The amount of S02 capable of being consumed by the catalyst / sorbent will be referred to as the catalyst / sorbent capacity. It was concluded from a short capacity study. 1. When the sorption / desorption temperature increases, the capacity increases. 2. When the catalyst / sorbent charge is increased, the capacity increases. 3. When the noble metal content in the catalyst / sorbent is increased, the capacity is increased. The catalyst / sorbent used during this study was coated inside a ceramic honeycomb carrier. The catalyst / sorbent / carrier contains 3.48 grams / inches3 of Ti02 / Pt with a platinum content of 0.5%. The capacity of this sample was determined to be 20 cc of S02 / inches3. This value was determined with an advance of S02 less than 10%, therefore, 20 cc is a minimum value. The experimental data given to the molar ratio of S02 / Pt of 10 during saturation of the catalyst / sorbent. A theory which is not intended to reduce the scope of the present invention is that this large excess of S02 sorbed suggests that the role of platinum is not a sorbent. Platinum under this theory promotes the sorption of S02 through the catalytic oxidation of S02 and the sulfur subsequently sucks into the surface of TI02 / Pt conditioned. The capacity of a Ti02 / Pt / Cu system was examined in a manner similar to that directed with the Ti02 / Pt system. The results were almost identical. The conclusions were: 1. When the sorption / desorption temperature increases, the capacity increases. 2. When the charge of Ti02 / Pt is increased, the capacity increases. 3. When the content of platinum in Ti02 / Pt is increased, the capacity increases. The copper modifier had a minor effect on the sorbent capacity. According to the present invention, the sulfur can be captured and released by the catalyst / sorbent, for example, a Ti02 / Pt system at temperatures as low as 148.8 ° C (300 ° F), however, the desorbed components released during regeneration they consist mainly of a mixture of H2S and S02. The H2S / S02 ratio depends on the residence time and / or the presence of modifiers. In some applications, H2S may not be desirable; since it could preferably release the sulfur components as S02. The nature of the desorbed sulfur components can be changed by adding a modifier to the catalyst / sorbent. A variety of modifiers have been used, but to date the most efficient have been copper, silver and bismuth. It has been found that the addition of modifiers to the catalytic sorbent increases the sulfur release by S02 and decreases or inhibits the formation of H2S. The modifiers can be deposited directly inside the catalyst / sorbent or deposited inside. A variety of modifiers were determined to work; however, the most efficient ones were found to be copper, bismuth and silver. The modifiers were also examined without a noble metal, for example, Pt, ie, only sorbent in the thin coating, for example, Ti02 / Cu. Although many were examined and found to capture the sulfur, the release of SO2 or H2S during the regenerations was not carried out and the sorbents are soon saturated. This is illustrated in Figure 9 where the consecutive 60 ppm S02 sorption cycles were carried out with a Ti02 / Cu sample. The intermediate regenerations followed each sorption cycle. The results show decreased elimination efficiency with each run. By adding the modifier, for example, Cu to the catalyst / sorbent, the S02 captured during the sorption cycles was found to be released during the standard regeneration cycles. This is illustrated in Figure 5, where the sorption and desorption cycles reach 7.7 cc of S02. The sulfur released during the regeneration was S02. No H2S was detected during this regeneration. The charge of the Cu (N03) 3 precursor in the catalyst / sorbent used in Figure 5 was 0.3 g / inch3. Figure 6 illustrates the effect of Cu (N03) 3 loading on the proportion of sulfur released as S02 and H2S. This figure shows that in the vicinity of 0.3 g / inches3 and above, all the sulfur compounds released during the regenerations were released as S02; however, under 0.3 g / in3 of H2S are released and the amount of H2S released increases with the Cu (N03) 3 load decreased. This effect was also observed with the other T 02 / Pt / X (where X is the metal modifier as defined) modifiers such as bismuth and silver. The ability to change the H? S / S02 ratio with the modifier load is a tremendous advantage of this new technology. The ability to adsorb sulfur from a dilute stream and then release it in a concentrated stream with a ratio of H2S / S02 suitable for use in the Claus process has therefore not been described. Figure 6 clearly illustrates that the charge of Cu (N03) 2 can be used for this purpose. Figure 12 shows the removal efficiency of S02 from the T? 02 / Pt system at various temperatures and the removal efficiency of the Ti02 / Pt / Cu system at 326.66 (620 ° F). From this figure, it is evident that the capacity of the Ti02 / Pt system increases with temperature. The role of copper and other modifiers arises to reside solely in the change of catalyst regeneration to decrease the formation of H2S. By increasing the internal concentration of S02 or lengthening the sorption time, the Ti02 / Pt catalyst / sorbent will eventually be saturated; therefore, producing advance of S02. This is illustrated in Figure 2 where a sorption run of 500 ppm and 60 ppm was conducted for 10 minutes. Figure 2 shows that there is no evidence of advance of S02 during the 60 ppm run. The run of 500 ppm, in contrast, shows the advance. During this sorption run, the advance of S02 is relatively low (< 40 ppm) during the first 3 minutes, however, after 3 minutes, the advance of S02 increases dramatically. This advance results when most of the sorption sites have been consumed. EXAMPLES The catalyst / sorbent used in the examples was prepared in a square-cell honeycomb of 200-cell-per-square-cord. The thin coating of Ti02 / Pt was prepared by incipient humidity. The content of Pt varies from 0.1 to 2.2%. After drying and calcination at 500 ° C, the solids were then dispersed in 7% acetic acid and milled in the ball overnight. The ceramic honeycombs were then immersed in the suspension and the thin / Pt coating, removed, blown and then dried at 150 ° C. The Ti02 / Pt / X samples were prepared by dipping the Ti? 2 / Pt honeycomb sample into a modifier solution. The sample was then removed, blown, and finally dried at 150 ° C. The catalyst / sorbents had a nominal composition as shown in Table 1. Table 1: Catalyst / sorbent composition (except as noted otherwise): Ti02 0.4 - 3.5 g / inch3 Pt 0 - .08 g / inch3 X 0 - 0.3 g / inches3 To test, the samples were placed in a 304 stainless steel tubular reactor and placed in a three-zone oven. The reactor was connected to a gas supply system which supplied mixed gases simulating a gas turbine exhaust. The gases were measured and controlled by Matheson mass flow transducers. The water was injected into a pre-heated oven using the Colé Palmer instrument number 74900 precision syringe pump. At least unless stated otherwise, the test gas compositions are given in Table 2 All sorption runs were conducted with a space velocity of 30,000 hours "1. Table 2: Test Gas Compositions Gas Component Concentration S02 30-500 ppm 02. 14-52% C02 3.05% H20 10.20% N2 Balance Before After passing the processed gas through the analytical instruments, the water was removed with a crystallizer.The dried gas was then analyzed with the instruments shown in Table 3. To measure H2S, the gas was first directed through H2S to the converter SO2 This converter consists of a stainless steel tube heated to 482.22 ° C (900 ° F) During the regenerations, oxygen was added to the gas before entering the converter.The laboratory tests with calibration gas showed virt 100% conversion of H2S to S02. During some experiments the H2S was measured with a BOVAR analyzer model 922. Table 3: Analytical Instruments Used During the Constituent Test of Gas Instrument S02 BOVAR model 721-M CO TECO model 48 NO, N02 TECO model IOS NH3 TECO model 300 / 10S C02 Horiba DAY model 510 H2S BOVAR model 922 The standard regeneration cycles were conducted with the gas composition given in table 4 at a space velocity of 2000 hour-1. Table 4: Regeneration of Gas Composition Component of Gas Concentration CO 0. 02% C02 1. 00% N2 57. 14% H20 4 0. 8 4% H2 4. 00% Catalytic Preparation The catalyst for the following examples was prepared as follows: - ceramic honeycomb carrier. - sorbent component of 2.2 g / inches3. - Platinum loading from 0.25 to 1.1% by weight of the sorbent component. - Metal modifier prepared with the metal nitrate precursor (0.00 to 0.30 g / inches3). Example 1 Example 1 shows SO2 sorption runs of 30 minutes, 30 ppm with the systems Ti0, Ti02 / Pt, Zr02 / Pt and Ce02 / Pt at 148.8 ° C. With the Ti02 sample there is little capture of S02, however, the catalysts / sorbents of Ti02 / Pt, Zr02 / Pt and Ce02 / Pt are significant S02 captured as shown in Figure 1. This illustrates the effectiveness of Ti, Zr , and Ce and the importance of the noble metal component. The load of T: -02 2.18 g / inches3; load of X02 / Pt 2.18 g / inches3; 1.1% Pt where X = Ti, Zr or Ce. Example 2 Example 2 illustrates the concentration effect of Input SO2 (60 ppm against 500 ppm) for 10 minutes, sorption runs of 260 ° C (500 ° F) with a Ti02 / Pt catalyst / sorbent (2.18 g / inch3, 0.5% Pt). Figure 2 shows advance of S02 with the upper input of S02 (500 ppm). This advance results when the catalyst / sorbent is saturated. After or during saturation, the catalyst / sorbent can be revitalized with a reducing gas or a thermal desorption. Example 3 Example 3 shows the regeneration of a TiO2 / Pt catalyst / sorbent partially saturated at 260 ° C (500 ° F). The regeneration of the catalyst / sorbent revitalizes the sorbent and produces a concentrated stream of sulfur compounds with the primary compound being H2S. The regeneration cycle was about 10 minutes as shown in Figure 3. Example 4 Example 4 shows the amount of sulfur captured and Released with a Ti02 / Pt catalyst / sorbent during a 30 minute sorption cycle of S02 of 30 ppm to 260 ° C (500 ° F) and a standard desorption cycle at 260 ° C (500 ° F). The results in Figure 4 show that the amount of sulfur compounds desorbed was equivalent to the amount of S02 sorbed during the previous sorption cycle and that the desorbed gas was composed of a mixture of H2S and S02. Example 5 Example 5 shows the amount of sulfur sorbed and desorbed with a sample of Ti02 / Pt / Cu during sorption cycles of SC2, of 60 ppm of 20 minutes at 260 ° C (500 ° F) and a desorption cycle standard at 260 ° C (500 ° F). The results in Figure 5 demonstrate that the amount of sulfur components desorbed was equivalent to the amount of S02 sorbed during the previous sorption cycle and that the desorbed components were mainly SO2. Example 6 Example 6 shows the effect of copper loading (metal modifier) in the proportion of sulfur released as S02 or H2S during the regeneration cycles of Ti / 2 / Pt sorbent / partially saturated catalyst. This example shows in Figure 6 that with 0.3 g / in3 of Cu (N03) 2 and greater, all of the sulfur is released as S02. Without Cu (N03) 2, 90% of the sulfur is released as H2S and 10% is released as S02. This effect was also obtained with other modifiers. Example 7 Example 7 shows the capture of S02 during 20 minutes, sorption cycles of 60 ppm using Ti? 2 / Pt with Cu, Ag and Bi modifiers (Ti02 / Pt / Cu 2.18 g / inches3; 1.1% of Pt; 0.3 g / inches3 X (N03) y; where X = Cu, Ag, Bi).

All exhibit similar characteristics with initial capture efficiency of 100% until reaching a point where the advance of SO2 began. The advance amount then increases steadily with time as can be seen in Figure 7. EXAMPLE 8 Example 8 demonstrates the SO2 released during the regeneration of the catalyst Ti / 2 / Pt sorbent with metal modifiers Bi, Ag and Cu. These regenerations continue for 20 minutes, SO2 sorption cycles of 30 ppm and appear to be at least identical with the release of SO2 as shown in Figure 8. Example 9 Example 9 illustrates SO2 sorption cycles of 60 ppm consecutively, with a Ti02 / Cu modifier / sorbent (2.18 g / inches3 of Ti02); 0.3 g / in3 Cu (N03) 2) without a noble metal component at 260 ° C (500 ° F). This result shown in Figure 9 illustrates that the Ti02 / metal modifier will capture the sulfur, however, the catalyst / sorbent is not regenerated during the regeneration cycle. Example 10 Example 10 illustrates the effect of Pt loading on the advance of SO2 during SO2 sorption cycles of 600 ppm with a catalyst / sorbent of TiO2 / Pt / Cu (2.18 g / in3 of TiO2 / Pt: 0.3 g / inches3 of Cu (N03) 2) at 260 ° C (500 ° F). Figure 10 shows that the Ti02 / Pt / Cu efficiency is directly related to the Pt load, such as the height of the load at the height of the sulfur capture capacity. Example 11 Example 11 illustrates the effect of oxygen in the boiler tube gas for 25 minutes, the sorption cycles of SO2 250 ppm, with a catalyst sorbed from Ti02 / Pt / Cu at 260 ° C (500 ° F). Figure 11 shows that the sorption of the sulfur components is significantly reduced in the absence of oxygen. Example 12 Example 12 shows the sulfur removal efficiency obtained for 75 minutes, S02 sorption runs, 60 ppm with a catalyst / sorbent of Ti02 / Pt at various temperatures and a catalyst / sorbent of Ti? 2 / Pt / Cu at 326.66 (620 ° F) is shown. Figure 12 shows that the removal efficiency increases with temperature and that the removal efficiency is slightly decreased by the addition of the metal modification. Example 13 Example 13 shows that H2S is removed during the sorption cycles with the Ti02 / Pt and Ti02 / Pt / Cu catalysts / sorbents at 260 ° C (500 ° F). Figure 13 shows the results and shows that H2S is also captured by the catalyst / sorbents. Example 14 Example 14 shows that the sulfur is released mainly as H2S during a desorption run of a partially saturated TiO2 / Pt sorbed catalyst at 260 ° C (500 ° F). The previous sorption run used at 20 minutes, H2S cycles of 20 ppm at 260 ° C (500 ° F). This result shown in Figure 14 demonstrates that the catalyst / sorbent can be regenerated after the capture of H2S. Example 15 In this Programmed Temperature Desorption (TPD) experiment a 4 minute sorption cycle with 100 ppm S02 was conducted at 148.8 ° C (300 ° F) (13 cc Ti02 / Pt, 3.0 g / in3 Ti02 : 11% of Pt), space velocity = 30,000 hours "1) .Then, the temperature was increased to 482.22 ° C (900 ° F), the nitrogen was then passed over the catalyst as a space velocity of 30,000 hours-1 , from the TPD experiment it was determined that all the sulfur captured during the 4 minute run cycle was released during the high temperature regeneration, however, no H2S was detected, therefore all the sulfur released was in the form of S02 This illustrates that H2S formation occurs only in the presence of H2 Figure 15 shows that sulfur is released in two pulses, the first being more defined than the second Example 16 In this Temperature Desorption Programmed (TPD), a sorption cycle of 10 minut with 250 ppm of S02 was conducted at 260 ° C (500 ° F) (13 cc of Ti02 / Pt, 3.0 g / in3 with Ti02: 1% of Pt), space velocity = 20,000 hours "1). After, the temperature was increased to 482.22 ° C (900 ° F), then air (approximately 20.9% of 02) was passed over the catalyst for 10 minutes at a space velocity of 10,000 hours-1. During desorption S02 or H2S was not detected, however, the continuous cyclization showed that the Ti0 / Pt catalyst / sorbent was revitalized during each air regeneration of 482.22 ° C (900 ° F). This is illustrated in Figure 16. The regeneration gas was also burned through isopropanol and analyzed by sulfur. A significant amount of dissolved sulfur was found suggesting that S03 was released during the regenerations.

Claims (40)

1. CLAIMS 1. A process for removing gaseous sulfur compounds from gaseous streams, comprising contacting a gaseous stream, containing gaseous sulfur compounds with a catalyst / sorbent under sulfur sorbent conditions, such a catalyst / sorbent comprising a noble metal component and a metal oxide sorbent component selected from the group consisting of Ti, Zr, Hf, Ce, Al, Si and mixtures thereof and removing a portion of gaseous sulfur compounds from the current. 2. -II process in accordance with the claim 1, characterized in that the noble metal component comprises Pt, Pd, Ph, Ru or mixtures thereof. 3. The process in accordance with the claim 2, characterized in that the noble metal comprises Pt. 4. The process in accordance with the claim 1, characterized in that the metal oxide sorbent component is an oxide of Ti, Zr, Hf, Ce or mixtures thereof. 5. The process in accordance with the claim 2, characterized in that the metal oxide sorbent component is an oxide of Ti, Zr, Hf, Ce or mixtures thereof. 6. The process in accordance with the claim 1, characterized in that a modifier consisting of an oxide Ag, Cu, Bi, Sb, Sn, As In, Pb, Au or mixtures thereof is present as a component of the catalyst / sorbent. 7. The process in accordance with the claim 6, characterized in that the modifier is Cu, Ag, Bi, or mixtures thereof. 8. The process in accordance with the claim 7, characterized in that the modifier consisting of an oxide of Ag, Cu, Bi, Sb, Sn, As In, Pb, Au or mixtures thereof is present as a component of the catalyst / sorbent. 9. The process in accordance with the claim 8, characterized in that the modifier is an oxide Cu, Ag, Bi or mixtures thereof. The process according to claim 5, characterized in that a modifier consisting of an oxide Ag, Cu, Bi, Sb, Sn, As In, Pb, Au or mixtures thereof is present as a component of such catalyst / sorbent 11. The process according to claim 10, characterized in that the modifier is a Cu oxide, Ag, Bi or mix them. 12. The process in accordance with the claim 9, characterized in that the modifier is a Cu oxide. 13. The process according to claim 9, characterized in that the modifier is Ag oxide. 14. The process according to claim 9, characterized in that the modifier is oxide Bi. 15. The process according to claim 1, characterized in that the gaseous sulfur-containing current-containing compound is terminated and the sulfur components sorbed are desorbed from the catalyst / sorbent by contacting the catalyst / sorbent with a gas stream of regeneration under desorption conditions of the sulfur compound whereby the catalyst / sorbent is regenerated to be re-used in the sorbent. 16. The process in accordance with the claim 15, characterized in that the regeneration gas comprises an inert carrier and a reduction component. 17. The process in accordance with the claim 16, characterized in that the inert gas is nitrogen, helium, argon or steam. 18. The process according to claim 16, characterized in that the reduction component is hydrogen, methane, hydrocarbons from Ci to C? 2 or mixtures thereof. 19. The process according to claim 15, characterized in that the regeneration gas is nitrogen, helium, argon or steam. 20. The process according to claim 15, characterized in that the regeneration gas comprises oxygen. 21. The process according to claim 15, characterized in that the regeneration gas is nitrogen, helium, argon or steam with oxygen present. 22. The process according to claim 15, characterized in that the residual gaseous sulfur containing vapcr and reducing agent is added without carrying a gas. 23. The process in accordance with the claim 15, characterized in that an amount of fuel gas is added during the regeneration to reach the desorption temperature to facilitate thermal desorption. 24. A regenerable catalyst / sorbent for removing gaseous sulfur compounds from gaseous streams comprising a noble metal catalytic component, a metal oxide sorbent component, selected from Ti, Zr, Hf, Ce, Al, Si or mixtures thereof and up to 0.3 g / inches3 of a modifying component consisting of an oxide of Ag, Cu, Bi, Sb, Sn, As, In, Pb, Au or mixtures thereof. The catalyst / sorbent according to claim 24, characterized in that the noble metal component is Pt, Pd, Rh, Ru or mixtures thereof. 26. The catalyst / sorbent according to claim 25, characterized in that the noble metal component is Pt. 27. The catalyst / sorbent according to claim 24, characterized in that the metal oxide sorbent component is an oxide of Ti, Zr, Hf, Ce or mixtures thereof. The catalyst / sorbent according to claim 25, characterized in that the metal oxide sorbent component is an oxide of Ti, Zr, Hf, Ce or mixtures thereof. 29. The catalyst / sorbent according to claim 24, characterized in that the modifying component is an oxide of Cu, Ag, Bi or mixtures thereof. 30. The catalyst / sorbent according to claim 25, characterized in that the modifying component is an oxide of Cu, Ag, Bi or mixtures thereof. 31. The catalyst / sorbent according to claim 24, characterized in that the modifying component is Cu oxide. 32. The catalyst / sorbent according to claim 24, characterized in that the modifying component is an Ag oxide. 33. The catalyst / sorbent according to claim 24, characterized in that the modifying component is an oxide of Bi. 34. A catalytic structure comprising a monolith carrier and a regenerable catalyst / sorbent for removing gaseous sulfur compounds from gaseous streams comprising a noble metal catalytic component, a metal oxide sorbent component, selected from Ti, Zr, Hf, Ce, Al, Si or mixtures thereof and up to 0.3 g / inches3 of a modifying component consisting of an oxide of Ag, Cu, Bi, Sb, Sn, As, In, Pb, Au or mixtures thereof deposited in the carrier. 35. The catalytic structure according to claim 34, characterized in that the catalyst / sorbent comprises 1 to 50% by weight of the total weight of the carrier and catalyst / sorbent. 36. The catalytic structure according to claim 35, characterized in that the noble metal component comprises 0.005 to 20.0% by weight of the catalyst / sorbent. 37. The catalytic structure according to claim 36, characterized in that the metal oxide sorbent component comprises from 70 to 99% by weight of the catalyst / sorbent. 38. The catalytic structure according to claim 37, characterized in that the modifying component comprises from 1 to 10% by weight of the catalyst / sorbent. 39. A method for adjusting the amount of H2S and SO2 in a regeneration stream comprising: contacting a first gaseous sulfur-containing compound containing current in a first concentration of sulfur compounds in a first concentration with a catalyst / sorbent which comprises 0.005 to 20% by weight of the noble metal catalyst component, 70 to 99% by weight of the metal oxide sorbent component, selected from Ti, Zr, Hf, Ce, Al, Si or mixtures thereof and 0 to 10% of the modifier consisting of an oxide of Ag, Cu, Bi, Sb, Sn, As, In, Pb, Au or mixtures thereof under conditions to remove a portion of sulfur compounds from the gas stream inside the catalyst / sorbent; removing a portion of the sulfur compounds from gaseous sulfur containing current; terminate the gaseous sulfur compound containing current; contacting the catalyst / sorbent with a regeneration gas to remove sulfur compounds from the catalyst / sorbent within the regeneration of a second concentration to form a second gaseous sulfur compound containing a stream comprising the regeneration gas and component of the gaseous sulfur compound comprising S02 or a mixture of S02 and HS; wherein the composition of the sulfur compound component is adjustable by the amount of modifier present in such a catalyst / sorbent. 40. The method according to claim 39, characterized in that the amount of H2S is decreased from 90 to 0% and the S02 increased from 10 to 100% as the present modifier increases from 0 to 10% by weight.