Composition for removing sulfur-containing compounds

Abstract

Provided is a composition for removing a sulfur-containing compound contained in at least one of a liquid and gas, the sulfur-containing compound being at least one selected from the group consisting of hydrogen sulfide and an —SH group-containing compound, the composition containing an aldehyde and an amine whose conjugate acid has a pKa value of 11.3 or higher in water at 25° C.

Claims

1. A composition, comprising: an aldehyde; and at least one of an amine of formula (1) and an amine of formula (2): ##STR00003## wherein R.sup.1 to R.sup.11 are each independently a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, provided that R.sup.1, R.sup.2, R.sup.7, and R.sup.8 may be connected to R.sup.3, R.sup.6, R.sup.9, and R.sup.11, respectively, to form an alkylene group having 2 to 6 carbon atoms; a pKa value of the conjugate acid of the amine of formula (1) and the amine of formula (2) is 11.3 or higher in water at 25° C., and the composition is suitable for removing a sulfur-containing compound selected from the group consisting of hydrogen sulfide and an —SH group-containing compound from at least one of a liquid and gas.

2. The composition according to claim 1, wherein the compound of formula (1) is at least one of 1,8-diazabicyclo[5.4.0]-7-undecene (DBU) and 1,5-diazabicyclo[4.3.0]-5-nonene (DBN).

3. The composition according to claim 1, wherein the compound of formula (2) is at least one selected from the group consisting of guanidine, 1,1,3,3-tetramethylguanidine (TMG), 1,5,7-triazabicyclo[4.4.0]dec-5-ene (TBD), and 7-methyl-1,5,7-triazabicyclo[4.4.0]dec-5-ene (MTBD).

4. The composition according to claim 1, wherein the aldehyde is an α, β-unsaturated aldehyde.

5. The composition according to claim 4, wherein the α, β-unsaturated aldehyde is at least one selected from the group consisting of acrolein, senecioaldehyde, and citral.

6. The composition according to claim 1, wherein each of the liquid and gas comprises a hydrocarbon.

7. The composition according to claim 1, wherein each of the liquid and gas is at least one selected from the group consisting of natural gas, liquefied natural gas (LNG), liquefied petroleum gas (LPG), sour gas, dry gas, wet gas, oil field gas, associated gas, tail gas, dimethyl ether, crude oil, naphtha, heavy aromatic naphtha, gasoline, kerosene, diesel oil, light oil, lubricating oil, heavy oil, A-heavy oil, B-heavy oil, C-heavy oil, jet fuel oil, FCC slurry, asphalt, condensate, bitumen, extra heavy oil, tar, gas to liquid (GTL), coal to liquid (CTL), asphaltene, aromatic hydrocarbons, alkylates, base oil, kerogen, coke, black oil, synthetic crude oil, reformed gasoline, isomerate gasoline, regenerated heavy oil, residual oil, clean oil, raffinate, wax, biomass fuel, biomass to liquid (BTL), biogasoline, bioethanol, bio-ETBE, and biodiesel.

8. A method of removing a sulfur-containing compound contained in at least one of a liquid and gas, the sulfur-containing compound being at least one selected from the group consisting of hydrogen sulfide and an —SH group-containing compound, the method comprising bringing the at least one of the liquid. and gas into contact with the composition according to claim 1.

9. The method according to claim 8, wherein the sulfur-containing compound is brought into contact with the composition in the range of −30° C. to 150° C.

Description

EXAMPLES

(1) The present invention will be described in more detail below with reference to examples. However, the present invention is not limited to the examples.

(2) Various materials used in Examples and Comparative Examples are shown below.

(3) <Hydrocarbon>

(4) Kerosene: manufactured by Wako Pure Chemical Industries, Ltd. density=0.8 g/cm.sup.3 Crude oil: manufactured by Japan Petroleum Exploration Co., Ltd., density=0.8 g/cm.sup.3
<Sulfur-Containing Compound> n-Butyl mercaptan (BuSH): manufactured by Wako Pure Chemical Industries, Ltd., density=0.83 g/cm.sup.3 Ethyl mercaptan (EtSH): manufactured by Wako Pure Chemical Industries, Ltd., density=0.84 g/cm.sup.3
<Aldehyde> Senecioaldehyde (SAL): synthesized from prenol in accordance with a method described in JP 60-224652 A (purity: 98.1% by mass), density=0.87 g/cm.sup.3 Acrolein: manufactured by Tokyo Chemical Industry Co. Ltd., purity>95% by mass, containing hydroquinone as a stabilizer, density=0.84 g/cm.sup.3 Citral: synthesized from prenol in accordance with JP 52-148009 A (purity: 97.0% by mass), density=0.89 g/cm.sup.3
<Amine> 1,8-Diazabicyclo[5.4.0]-7-undecene (DBU): manufactured by Wako Pure Chemical Industries, Ltd., pKa=11.5, density=1.02 g/cm.sup.3 1,1,3,3-Tetramethylguanidine (TMG): manufactured by Wako Pure Chemical Industries, Ltd., pKa=13.6, density=0.92 g/cm.sup.3 Triethylamine: manufactured by Wako Pure Chemical Industries, Ltd., pKa=10.8, density=0.73 g/cm.sup.3 N,N,N′,N″,N″-Pentamethydiethylenetriamine (PMDETA): manufactured by Wako Pure Chemical Industries, Ltd., pKa=9.1, density=0.83 g/cm.sup.3
<Solvent> Solvent naphtha: manufactured by Sankyo Chemical Co. Ltd. (Solvent #100), density=0.88 g/cm.sup.3 Diethylene glycol dimethyl ether: manufactured by Wako Pure Chemical Industries, Ltd., density=0.94 g/cm.sup.3 methyl laurate: manufactured by Wako Pure Chemical Industries, Ltd., density=0.87 g/cm.sup.3

Example 1

(5) In a 100 mL three-neck flask, 50 mL of kerosene was put and 50 μL (1000 ppm by volume, 0.46 mmol) of BuSH was added thereto to obtain a kerosene solution containing a sulfur-containing compound.

(6) Next, 250 μL (2.59 mmol) of SAL and 250 μL (1.71 mmol) of DBU were added to the kerosene solution, and the solution was stirred at room temperature (20° C.±5° C., the same applies hereinafter) and at 800 rpm to perform a sulfur-containing compound removal reaction.

(7) After 1-day reaction, the mercaptan concentration of the liquid phase in the three-neck flask was measured. Then, the mercaptan concentration was 122 ppm by volume and the removal rate was 88%.

(8) The mercaptan concentration of the liquid phase was measured using a calibration curve method by gas chromatography. The gas chromatography was performed under the following conditions.

(9) (Gas Chromatography)

(10) Analyzer: GC-SCD (manufactured by Agilent Technologies Japan, Ltd.)

(11) Detector: sulfur chemiluminescence detector (SCD)

(12) Column: DB-sulfur SCD (length: 60 m, thickness: 4.2 μm, inner diameter: 0.32 mm) (manufactured by Agilent Technologies Japan, Ltd.)

(13) Analytical conditions: inject. temp. 250° C., detect. temp. 250° C.

(14) Temperature rise condition: 35° C. (kept for 3 minutes) (raised at 10° C./min).fwdarw.250° C. (kept for 15 minutes)

(15) Internal Standard Substance: diphenyl sulfide

Comparative Example 1

(16) A sulfur-containing compound removal reaction was performed in the same manner as in Example 1 except that no amine was used. The result is shown in Table 1.

Example 2 and Comparative Examples 2 and 3

(17) A sulfur-containing compound removal reaction was performed in the same manner as in Example 1 except that amines shown in Table 1 were respectively used in place of DBU. The result is shown in Table 1.

Example 3

(18) A sulfur-containing compound removal reaction was performed in the same manner as in Example 1 except that the amount of DBU added was changed from 250 μL to 25 μL (0.17 mmol). The result is shown in Table 1.

Example 4

(19) A sulfur-containing compound removal reaction was performed in the same manner as in Example 3 except that acrolein was used in place of SAL and the reaction time was changed from 1 day to 2 hours. The result is shown in Table 1.

Comparative Example 4

(20) A sulfur-containing compound removal reaction was performed in the same manner as in Example 4 except that no amine was used and the reaction time was changed from 2 hours to 1 day. The result is shown in Table 1.

Example 5

(21) A sulfur-containing compound removal reaction was performed in the same manner as in Example 3 except that EtSH was used in place of BuSH. The result is shown in Table 1.

Example 6

(22) A sulfur-containing compound removal reaction was performed in the same manner as in Example 3 except that crude oil was used in place of kerosene. The result is shown in Table 1.

(23) TABLE-US-00001 TABLE 1 Sulfur-containing compound Aldehyde Incorporated Incorporated Amine Evaluation amount amount Incorporated Reaction Removal Hydrocarbon (50 μL) (250 μL) Type pKa amount (μL) time rate (%) Example 1 kerosene BuSH SAL DBU 11.5 250 1 day 88 Comparative kerosene BuSH SAL None 1 day <10 Example 1 Example 2 kerosene BuSH SAL TMG 13.6 250 1 day 60 Comparative kerosene BuSH SAL triethylamine 10.8 250 1 day <10 Example 2 Comparative kerosene BuSH SAL PMDETA  9.1 250 1 day 10 Example 3 Example 3 kerosene BuSH SAL DBU 11.5  25 1 day 29 Example 4 kerosene BuSH acrolein DBU 11.5  25 2 hours 99 Comparative kerosene BuSH acrolein None 1 day 15 Example 4 Example 5 kerosene EtSH SAL DBU 11.5  25 1 day 43 Example 6 crude oil BuSH SAL DBU 11.5  25 1 day 73

Example 7

(24) In a 100 mL three-neck flask, 50 mL of crude oil was put and 30 μL (596 ppm by mass, 0.36 mmol) of EtSH was added thereto to obtain a crude oil solution containing a sulfur-containing compound.

(25) Next, 300 μL (2.59 mmol as SAL) of a mixture composed of 80% by mass of SAL which was separately prepared and 20% by mass of DBU was added to the crude oil solution and the solution was stirred at room temperature at 800 rpm to perform a sulfur-containing compound removal reaction.

(26) After a 7-hour reaction, the mercaptan concentration of the liquid phase in the three-neck flask was measured. Then, the mercaptan concentration was 145 ppm by mass and the removal rate was 76%.

(27) As shown in Examples 1 to 7, it was confirmed that when an aldehyde and an amine having a pKa value of 11.3 or higher were used in combination, mercaptan (a sulfur-containing compound) in the liquid was able to be removed more efficiently as compared with the case of using an aldehyde alone (Comparative Examples 1 and 4) or the case of using an aldehyde and an amine having a pKa value less than 11.3 in combination (Comparative Examples 2 and 3).

Example 8

(28) In a 100 mL three-neck flask, 50 mL of crude oil was put and hydrogen sulfide gas (hydrogen sulfide: 99.99% by volume) was allowed to flow at a rate of 10 mL/min for 45 minutes to obtain a crude oil solution with hydrogen sulfide absorbed. The crude oil solution was transferred to another 100 mL three-neck flask, and was diluted with crude oil into 50 mL. After dilution, the hydrogen sulfide concentration of the liquid phase in the diluted crude oil solution was 465 ppm by mass (0.53 mmol).

(29) Next, 75 μL (0.62 mmol as SAL) of a mixture composed of 91% by mass of SAL which was separately prepared and 9% by mass of DBU was added to the diluted crude oil solution, and the solution was stirred at room temperature at 800 rpm in the three-neck flask to perform a sulfur-containing compound removal reaction.

(30) After 3-hour reaction, the hydrogen sulfide concentration of the liquid phase in the three-neck flask was measured. Then, the concentration was 303 ppm by mass and the removal rate was 35%.

(31) The hydrogen sulfide concentration of the liquid phase was measured using a calibration curve method by a gas chromatography as in the mercaptan concentration.

(32) As shown in Example 8, it was confirmed that the case of combination use of an aldehyde and an amine having a pKa value of 11.3 or higher was also excellent in the removal rate of hydrogen sulfide in the liquid.

Example 9

(33) In a 100 mL three-neck flask, 30 mL of kerosene was added, a mixed gas composed of 1% by volume of hydrogen sulfide and 99% by volume of nitrogen was allowed to flow at a rate of 50 mL/min while stirring at 800 rpm to substitute the gas in the three-neck flask. After 1 hour, flow of the mixed gas was stopped, and after sealing the three-neck flask, the hydrogen sulfide concentration of the gas phase in the three-neck flask was measured. Then, the concentration was 8400 ppm by volume.

(34) Next, to the kerosene solution, 1 g (10.7 mmol as SAL) of a mixture composed of 90% by mass of SAL which was separately prepared and 10% by mass of DBU was added, and the solution was stirred at room temperature at 800 rpm in the three-neck flask to perform a sulfur-containing compound removal reaction.

(35) After a 30-minute reaction, the hydrogen sulfide concentration of the gas phase in the three-neck flask was measured. Then, the concentration was 0 ppm by volume and the removal rate was 100%.

(36) The hydrogen sulfide concentration in the gas phase was measured using a Kitagawa gas detector tube system (used with a hydrogen sulfide gas detector tube, manufactured by Komyo Rikagaku Kogyo K. K., installed in a gas aspirating pump “AP-20”). Specifically, 4 mL of a gas sample was first taken from the gas phase in the three-neck flask, and the sample was diluted with 96 mL of air to prepare 100 mL of a measurement sample. Next, the measurement sample was allowed to flow into the gas aspirating pump and the indication of the gas detector tube after 1 minute was observed. Then, the indication was corrected by multiplying the indication by the dilution degree and the corrected value was taken as the hydrogen sulfide concentration of the gas phase.

Example 10

(37) A sulfur-containing compound removal reaction was performed in the same manner as in Example 9 except that a mixture composed of 90% by mass of SAL and 10% by mass of DBU was changed to a mixture (5.91 mmol as citral) composed of 90% by mass of citral and 10% by mass of DBU and a reaction time was changed from 30 minutes to 1 hour.

(38) In Example 10, the hydrogen sulfide concentration of the gas phase before the start of the reaction was 4800 ppm by volume, and the hydrogen sulfide concentration of the gas phase after a 1-hour reaction was 140 ppm by volume and the removal rate was 97%.

(39) As shown in Examples 9 and 10, it was confirmed that combination use of an aldehyde and an amine having a pKa value of 11.3 or higher enables efficient removal of hydrogen sulfide (a sulfur-containing compound) in a liquid and gas.

Reference Example 1

(40) Into a 9 mL sample tube, 2 g of kerosene was put, and 2 g of a mixture composed of 90% by mass of SAL and 10% by mass of DBU was added thereto and mixed. Then, the mixed liquid had a uniform appearance.

Reference Example 2

(41) An evaluation was performed in the same manner as in Reference Example 1 except for using solvent naphtha in place of kerosene. The resulting mixed liquid had a uniform appearance.

Reference Example 3

(42) An evaluation was performed in the same manner as in Reference Example 1 except for using diethylene glycol dimethyl ether in place of kerosene. The resulting mixed liquid had a uniform appearance.

Reference Example 4

(43) An evaluation was performed in the same manner as in Reference Example 1 except for using methyl laurate in place of kerosene. The resulting mixed liquid had a uniform appearance.

Reference Example 5

(44) Into a 500 mL eggplant flask, 360 g of diethylene glycol dimethyl ether was put, and 40 g of a mixture composed of 90% by mass of SAL and 10% by mass of DBU was added thereto and mixed. Then, the mixed liquid had a uniform appearance.

Reference Example 6

(45) The mixed liquid obtained in Reference Example 5 was stored at room temperature for 7 days, and was then analyzed for the content of SAL by gas chromatography. Then, the residual amount was 97% of the initial value.

Example 11

(46) Into a 250 mL gas wash bottle (with sintered filter), 200 mL of the mixed liquid obtained in Reference Example 5 was put, and a mixed gas composed of 0.1% by volume of hydrogen sulfide and 99.9% by volume of nitrogen was allowed to flow at a rate of 100 mL/min. After 1 hour flow, the hydrogen sulfide concentration in the gas phase at the outlet of the gas wash bottle was measured. Then, the concentration was 7 ppm by volume and the removal ratio was 99%.

(47) As shown in Reference Examples 1 to 6, it can be seen that, even when the composition of the present invention contains the solvent, a uniform solution can be given and the solution can be stored without degradation of the aldehyde. As shown in Example 11, it can be seen that the composition containing a solvent added thereto is also excellent in removal efficiency of a sulfur-containing compound.