1. A process for treating an alkylation feedstock comprising olefins, n-alkanes, and iso-alkanes, the process comprising:
contacting at least a portion of the alkylation feedstock with sulfuric acid in a reaction zone under conditions to form sulfate esters of the olefins;
separating the n-alkanes and the iso-alkanes from the sulfuric acid and the sulfate esters;
recovering the n-alkanes and the iso-alkanes in a first product stream; and
recovering the sulfate esters in a second product stream;
wherein the sulfuric acid has a strength that titrates as below 75 weight percent H2SO4water mixtures.
2. The process of claim 1, wherein the separating comprises decanting.
3. The process of claim 1, wherein the sulfuric acid has a strength that titrates as 30 to 40 weight percent H2SO4water mixtures.
4. The process of claim 1, wherein the contacting is at a temperature in the range from 0\xb0 F. to 40\xb0 F.
5. The process of claim 1, further comprising feeding at least a portion of the recovered sulfate esters to an alkylation reactor.
6. The process of claim 1, wherein the olefins comprise isoolefin, the process further comprising:
feeding the alkylation feedstock to an oligomerization reaction zone under conditions of temperature and pressure to oligomerize at least a portion of the iso-olefin;
separating the oligomers from the unreacted iso-olefin, olefins, n-alkanes, and iso-alkanes by fractionation;
recovering at least a portion of the unreacted iso-olefin, olefins, n-alkanes, and iso-alkanes for the contacting; and
recovering the oligomers.
7. The process of claim 6, further comprising feeding at least a portion of the recovered oligomers to an alkylation reactor.
8. The process of claim 6, wherein the iso-olefin comprises at least one of C4 iso-olefins, C5 iso-olefins, and mixtures thereof.
9. The process of claim 6, wherein the oligomers comprise dimers and trimers of the iso-olefin.
10. The process of claim 1, further comprising recycling at least a portion of the recovered iso-alkane and n-alkane to the reaction zone.
11. The process of claim 1, further comprising separating the recovered n-alkanes and iso-alkanes to form an iso-alkane-rich fraction and an n-alkane-rich fraction.
12. The process of claim 1, wherein the olefins comprise C3-C5 olefins, C3-C5 n-alkanes, and C3-C5 iso-alkanes.
13. A process for treating a C4-rich alkylation feedstock comprising n-butenes, n-butanes, and iso-butanes, the process comprising:
contacting at least a portion of the alkylation feedstock with sulfuric acid in a reaction zone under conditions to form sulfate esters of the n-butenes;
separating the n-butanes and the iso-butanes from the sulfuric acid and the sulfate esters;
recovering the n-butanes and the iso-butanes; and
recovering the sulfate esters;
wherein the sulfuric acid has a strength that titrates as below 75 weight percent H2SO4water mixture.
14. The process of claim 13, wherein the separating comprises decanting.
15. The process of claim 13, wherein the sulfuric acid has a strength that titrates as 30 to about 40 weight percent H2SO4water mixtures.
16. The process of claim 13, wherein the contacting is at a temperature in the range from 0\xb0 F. to 40\xb0 F.
17. The process of claim 13, further comprising feeding at least a portion of the recovered sulfate esters to an alkylation reactor.
18. The process of claim 13, wherein the alkylation feedstock further comprises isobutene, the process further comprising:
feeding the C4-rich alkylation feedstock to an oligomerization reaction zone under conditions of temperature and pressure to oligomerize at least a portion of the isobutene;
separating the isobutene oligomers from the unreacted isobutene, n-butenes, n-butanes, and iso-butanes by fractionation;
recovering at least a portion of the unreacted isobutene, n-butene, n-butanes, and iso-butanes for the contacting; and
recovering the isobutene oligomers.
19. The process of claim 18, further comprising feeding at least a portion of the recovered isobutene oligomers to an alkylation reactor.
20. The process of claim 13, further comprising recycling at least a portion of the recovered iso-butane and n-butane to the reaction zone.
21. The process of claim 13, further comprising separating the recovered n-butanes and iso-butanes to form an iso-butane-rich fraction and an n-butane-rich fraction.
22. A process for treating an alkylation feedstock comprising isoolefins, n-olefins, isoalkanes, and n-alkanes, the process comprising:
feeding the alkylation feedstock to an oligomerization reaction zone under conditions of temperature and pressure to oligomerize at least a portion of the isoolefin;
separating the oligomers from the unreacted isoolefin, olefins, n-alkanes, and iso-alkanes by fractionation;
recovering at least a portion of the unreacted isoolefin, olefins, n-alkanes, and iso-alkanes; and
recovering the oligomers
contacting at least a portion of the recovered unreacted isoolefin, olefins, n-alkanes, and iso-alkanes with sulfuric acid in a reaction zone under conditions to form sulfate esters of the olefins;
separating the n-alkanes and the iso-alkanes from the sulfuric acid and the sulfate esters;
recovering the n-alkanes and the iso-alkanes; and
recovering the sulfate esters;
wherein the sulfuric acid has a strength that titrates as below 75 weight percent H2SO4water mixtures.
23. The process of claim 22, further comprising feeding at least a portion of the recovered olefins and at least a portion of the recovered sulfate esters to an alkylation reactor.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A composition comprising at least one non-ionic surfactant and hydrophobic particles of metal oxide wherein the mean length of the primary particles is in the range from 50 to 90 nm, the mean width of the primary particles is in the range from 5 to 20 nm, and the median particle volume diameter of the secondary particles is less than 45 nm.
2. A composition in the form of an aqueous dispersion comprising at least one non-ionic surfactant and hydrophobic particles of metal oxide wherein the mean length of the primary particles is in the range from 50 to 90 nm, the mean width of the primary particles is in the range from 5 to 20 nm, and the median particle volume diameter of the secondary particles is less than 45 nm.
3. A composition comprising at least one non-ionic surfactant and hydrophobic particles of metal oxide having an extinction coefficient at 524 nm (E524) of less than 2.0 lgcm, an extinction coefficient at 450 nm (E450) of less than 3.0 lgcm, an extinction coefficient at 360 nm (E360) of greater than 3 lgcm, an extinction coefficient at 308 nm (E308) of greater than 30 lgcm, a maximum extinction coefficient E(max) of greater than 45 lgcm, and a \u03bb(max) in the range from 260 to 290 nm.
4. A composition in the form of a sunscreen product formed from a composition comprising at least one non-ionic surfactant and hydrophobic particles of metal oxide wherein the mean length of the primary particles is in the range from 50 to 90 nm, the mean width of the primary particles is in the range from 5 to 20 nm, and the median particle volume diameter of the secondary particles is less than 45 nm.
5. A composition according to claim 1 wherein the primary particles of metal oxide have a mean length in the range from 55 to 77 nm, preferably 60 to 70 nm.
6. A composition according to claim 1 wherein the primary particles of metal oxide have a mean width in the range from 8 to 19 nm, preferably 12 to 17 nm.
7. A composition according to claim 5 wherein at least 60% by number of the primary particles have a length in the range from 55 to 77 nm, preferably 60 to 70 nm andor at least 60% by number of the primary particles have a width in the range from 8 to 19 nm, preferably 12 to 17 nm.
8. A composition according to claim 1 wherein the median particle volume diameter of the primary particles of metal oxide is in the range from 25 to 31 nm, preferably 25 to 28 nm.
9. A composition according to claim 1 wherein the median particle volume diameter of the secondary particles of metal oxide is in the range from 22 to 30 nm, preferably 24 to 30 nm.
10. A composition according to claim 1 wherein no more than 16% by volume of the secondary particles of metal oxide have a volume diameter of less than 20 nm, preferably less than 22 nm.
11. A composition according to claim 1 wherein more than 84% by volume of the secondary particles of metal oxide have a volume diameter of less than 40 nm, preferably less than 30 nm.
12. A composition according to claim 1 wherein the particles of metal oxide comprise an organic water repellant coating.
13. A composition according to claim 1 wherein the metal oxide particles comprise (i) in the range from 65% to 95% by weight of titanium dioxide, (ii) in the range from 2% to 12% by weight of inorganic coating, preferably alumina, and (iii) in the range from 4% to 18% by weight of organic coating, preferably fatty acid andor salt thereof, all with respect to the total weight of the particles.
14. A composition according to claim 1 wherein the at least one non-ionic surfactant has a HLB value in the range from 5 to 20.
15. A composition according to claim 1 wherein the at least one non-ionic surfactant has a molecular weight in the range from 200 to 1500.
16. A composition according to claim 1 comprising a mixture of two non-ionic surfactants which differ in molecular weight by an amount in the range from 250 to 700.
17. A composition according to claim 2 wherein the aqueous dispersion comprises at least 35%, preferably at least 40% by weight of metal oxide particles.
18. A composition according to claim 1 wherein the particles of metal oxide have an extinction coefficient at 524 nm (E524) of less than 1.5, preferably less than 1.2 lgcm.
19. A composition according to claim 3 wherein the particles of metal oxide have an extinction coefficient at 524 nm (E524) in the range from 0.1 to 1.0 lgcm, an extinction coefficient at 450 nm (E450) in the range from 0.3 to 1.7 lgcm, an extinction coefficient at 360 nm (E360) in the range from 5 to 10 lgcm, an extinction coefficient at 308 nm (E308) in the range from 40 to 60 lgcm, a maximum extinction coefficient E(max) in the range from 55 to 75 lgcm, and a \u03bb(max) in the range from 260 to 290 mn.
20. A composition according to claim 1 wherein the particles of metal oxide particles have a photogreying index in the range from 1 to 10.
21. A composition according to claim 1 having a change in whiteness \u0394L of less than 3, preferably in the range from 0.5 to 2.5.
22. A composition according to claim 1 having a whiteness index in the range from 10% to 80%.
23. A composition according to claim 1 having a Sun Protection Factor (SPF) of greater than 15, preferably greater than 20.
24. A composition according to claim 1 which is transparent when applied to the skin.
25. The use of a composition comprising at least one non-ionic surfactant and hydrophobic particles of metal oxide wherein the mean length of the primary particles is in the range from 50 to 90 nm, the mean width of the primary particles is in the range from 5 to 20 nm, and the median particle volume diameter of the secondary particles is less than 45 nm, in the manufacture of a sunscreen having reduced whiteness.