Sulfinol process

The process is capable of achieving higher solubiHties of CO2 in the solution without the corrosion problems encountered with amine systems before the advent of Amine Guard. The Sulfinol process is used in over 50 plants worldwide nevertheless, it is used less often than the amine or carbonate processes. 

The Sulfinol process from Shell Development Company is a good example of the physical/chemical type of process. It blends a physical solvent and an amine to obtain the advantages of both. The physical solvent is Sulfolane (tetrahydrothiophene dioxide) and the amine is usually DIPA (diisopropanol amine). The flow scheme is the same as for an amine plant. ... 

Licensed by Shell the Sulfinol process combines the properties of a physical and a chemical solvent. The Sulfinol solution consists of a mixture of sulfolane (tetrahydrothiophene 1-1 dioxide), which is a physical solvent, diisopropanolamine (DIPA), and water. DIPA is a chemical solvent that was discussed under the amines. 

Sulfolane A process for removing aromatic hydrocarbons from petroleum fractions by liquid-liquid extraction using sulfolane (tetramethylene sulfone tetrahydrothiophene-1,1-dioxide) at approximately 190°C. Developed by Shell Development Company in 1959 and first commercialized in 1962 now licensed through UOP. It replaced the Udex process. Sulfolane is used for another purpose in the Sulfinol process. 

Sulfinates, 72 182 titanium, 25 119-120 Sulfinic acid salts, 23 658 Sulfinol process... 

Shell Sulfinol Process Di-isopropanolamine Dissolved in Sulfolane Water... 

The Shell Sulfinol process removes H2S, C02) COS (carbonyl sulfide), and organic sulfur compounds from natural gas by scrubbing with di-isopropanolamine dissolved in a mixture of sulfolane (C4H8SO2) and water. It was developed in the 1960 s by Shell. In 1997, over 200 commercial units were operating or under construction1. 

The advantages of the Sulfinol process over conventional amine treating systems include. 

Capital costs for a Sulfinol unit are lower than alkanolamine units that have the same capacity. This is because the equipment is smaller as a result of less foaming and lower circulation rates. However, certain treating applications may not be ideal for the Sulfinol process. A reclaimer may be needed to remove DIPA degradation products when C02 partial pressure is high. Also, aromatic and hydrocarbon co-absorption occurs when solvent -to-gas ratios are high260-... 

Table 5.34. Shell Sulfinol Process Typical Operating Data260...

Shell Sulfinol Process, Shell Global Solutions, Shell Oil Products Company, Houston, Texas, 2003 (www.sulfinol.com). 

Sulfur content of the feedstock presents no serious problem for SGP high-sulfur (e.g., 5%wt S) petroleum residues can serve as SGP feedstocks. The H2S and COS can be readily removed from the SGP product gas by any one of several well-proven desulfurization processes such as the Shell Sulfinol Process. 

The Shell Sulfinol Process is used for removal of acidic constituents such as H2S, CO2, COS, etc. from a gas stream. Improved performance over other processes is due to the use of an organic solvent, Sulfolane (tetrahydrothiophene dioxide), mixed with an aqueous alkanolamine. Relative proportions of Sulfolane, alkanolamine, and water, as well as the operating conditions, are tailored for each specific application. Simultaneous physical and chemical absorption under feed gas conditions is provided by this Sulfinol solvent. Regeneration is accomplished by release of the acidic constituents at near atmospheric pressure and a somewhat elevated temperature. The flow scheme (Figure 4) is very similar to that of an aqueous alkanolamine system since it involves only absorption, regeneration and heat exchange under typical alkanolamine treater conditions. 

The advantages which can be obtained when using the Sulfinol Process as compared to other treating systems are ... 

The physical solvents methanol (Rectisol process), sulfolane (Sulfinol Process) and N-rnethylpyrrolidone (Purisol) are preferentially used in the treatment of partial oxidation gases and will be described separately in the following section. 

The Sulfinol process [719]-[722] cannot strictly be classified as a physical solvent process, as the solvent is a mixture of sulfolane (tetrahydrothiophene 1,1-dioxide), DIPA (diisopropanolamine), and water in a ratio of about 45 40 10. Sulfolane is a true physical solvent, whereas the DIPA is a chemically acting component. To achieve a higher C02/H2S selectivity, DIPA may be substituted by MDEA (methyldiethanola-mine) in the M-Sulfinol process. In partial oxidation process a concept with two separate Sulfinol units is preferred the first ahead of the shift conversion (gas composition for example C02 5.4 vol%, H2S 0.5 vol%), and the second one for recovery of sulfur-free C02affer the shift conversion (feed gas for example C02 33vol%, H2S 0 vol %). 

Combinations of physical and chemical absorption are also used, as in Shell s Sulfinol process in which a mixture of diisopropanolamine and sulfolane in water is utilized. For the hydrogen sulfide-free gases from the steam-reforming process, chemical scrubbing with activated potassium carbonate solutions or alkanolamines is preferred. In the case of hydrogen sulfide-containing gases from the partial oxidation process, physical absorption alone or in combination with chemical absorption is preferred. 

The Sullinol process, developed by Shell in the early 1960s, is a combination process that uses a mixture of amines and a physical solvent. The Shell Sulfinol process is a regenerable amine process for acid gas removal. As the process uses a mixture of water, sulfolane, and one or more alkanolamine, removal capacity of COS, mercaptan s, and organic sulfides from gas streams is excellent by virtue of the improved physical solubility of these compounds in the solvent. A typical flow diagram of sulfinol process is shown in Figure 5.29.196... 

Figure 5.29. Schematic flow diagram of the sulfinol process.15...

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