1. A process of regenerating HF alkylation acid from a mixture comprising HF acid, water and polymer formed during an HF olefinisoparaffin alkylation process, which comprises:
stripping the mixture comprising HF acid, water, the polymer and hydrocarbons in a regeneration zone by means of a stripping fluid to form a vapor from the mixture,
withdrawing vapor from the regeneration zone and completely condensing the withdrawn vapor to form from the vapor a condensed liquid component comprising HF acid and water,
heating the condensed liquid component to vaporize HF acid and returning the vaporized HF acid directly to the regeneration zone to increase the concentration of the water in the remaining condensed liquid component to a value closer to the azeotropic waterHF acid value and
withdrawing the condensed liquid component having the increased concentration of water.
2. A process according to claim 1 in which the condensed liquid component is heated until an azeotropic mixture of water and HF acid is substantially attained.
3. A process according to claim 1 in which the stripping fluid comprises a C3-C5 isoparaffin.
4. A process according to claim 3 in which the isoparaffin is isobutane.
5. A process according to claim 1 in which the regeneration of the HF acid is carried out in a regeneration tower having a sidedraw in the vapor region through which the vapor from the regeneration zone is withdrawn into a vessel in which the heating of the condensed liquid component is carried out.
6. A process of regenerating HF alkylation acid from a mixture comprising HF acid and water formed during an HF olefinisoparaffin alkylation process in which a light C3-C5 isoparaffin is alkylated with a light C3-C5 olefin to form a hydrocarbon alkylate product in the gasoline boiling range, which comprises:
alkylating the light paraffin with the light olefin in the presence of HF alkylation acid as an alkylation catalyst to form an effluent comprising a hydrocarbon phase of hydrocarbon alkylate product and a separate phase of HF acid and water,
separating the hydrocarbon phase from the HF acid phase,
regenerating HF acid from a stream of the HF acid phase by stripping the stream in a regeneration zone by means of light isoparaffin as a stripping fluid, to vaporize HF acid and water from the stream,
withdrawing a vaporous portion of the fluid from the regeneration zone comprising vaporized HF acid and water and completely condensing the withdrawn vaporous portion to form a condensed liquid component comprising HF acid and water in a distillation zone,
heating the condensed liquid component in the distillation zone to vaporize HF acid and directly returning the vaporized HF acid to the regeneration zone, to increase the concentration of the water in the remaining condensed liquid component to a value closer to the azeotropic waterHF acid value and
withdrawing the condensed liquid component having the increased concentration of water from the distillation zone.
7. A process according to claim 6 in which the isoparaffin comprises isobutane.
8. A process according to claim 6 in which the condensed liquid component is heated until an azeotropic mixture of water and HF acid is substantially attained.
9. A process according to claim 6 in which the condensed liquid component is withdrawn periodically from the distillation zone.
10. A process according to claim 6 in which the regeneration of the HF acid in the regeneration zone by stripping the stream in the regeneration zone forms a phase comprising an acid soluble oil polymer product of the alkylation which is withdrawn from the regeneration zone.
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 method for enhancing angiogenesis in a mammal to achieve a therapeutic effect; the method comprising the step of administering to the mammal an effective amount of a polypeptide which consists essentially of residues 1 to 364 of SEQ ID NO:2 or a dimer thereof encoded by a nucleic acid comprising a coding region consisting of a nucleotide sequence at least 95% identical to a sequence selected from the group consisting of:
(a) a polynucleotide encoding a polypeptide consisting of amino acid residues 1-364 of SEQ ID NO: 2;
(b) a polynucleotide consisting of nucleotide residues 3428-4519 of SEQ ID NO: 1, which encodes amino acid residues 1-364 of SEQ ID NO: 2; and
(c) a polynucleotide that is hybridizable to a polynucleotide consisting of nucleotide residues 3428-4519 of SEQ ID NO: 1, which encodes amino acid residues 1-364 of SEQ ID NO: 2.
2. The method of claim 1 wherein the polypeptide consists essentially of residues 1 to 364 of SEQ ID NO:2 or a dimer thereof.
3. The method of claim 1 wherein the therapeutic effect comprises enhancing angiogenesis in a tissue graft in the mammal.
4. A method of treating a condition that would benefit from increased angiogenesis in a mammal comprising the step of administering to the mammal an angiogenically effective amount of a polypeptide which consists essentially of residues 1 to 364 of SEQ ID NO:2 or a dimer thereof encoded by a nucleic acid comprising a coding region consisting of a nucleotide sequence at least 95% identical to a sequence selected from the group consisting of:
(a) a polynucleotide encoding a polypeptide consisting of amino acid residues 1-364 of SEQ ID NO: 2;
(b) a polynucleotide consisting of nucleotide residues 3428-4519 of SEQ ID NO: 1, which encodes amino acid residues 1-364 of SEQ ID NO: 2; and
(c) a polynucleotide that is hybridizable to a polynucleotide consisting of nucleotide residues 3428-4519 of SEQ ID NO: 1, which encodes amino acid residues 1-364 of SEQ ID NO: 2.
5. The method of claim 4 wherein the polypeptide consists essentially of residues 1 to 364 of SEQ ID NO:2 or a dimer thereof.
6. The method of claim 4 wherein the condition that would benefit from increased angiogenesis comprises a myocardial infarction.