Process for purifying hydrocarbons

Patent metadata

Field	Value
Publication number	US-2016008735-A1
Application number	US-201414770649-A
Country	US
Kind code	A1
Filing date	Feb 26, 2014
Priority date	Feb 26, 2013
Publication date	Jan 14, 2016
Grant date	—

Abstract

A process for washing hydrocarbons said process comprising: (I) distilling a crude acetone mixture preferably obtained from the cleavage of cumene hydroperoxide and containing hydrocarbons and water so as to form a bottoms fraction containing said hydrocarbons in an organic phase and an aqueous phase; (II) contacting at least a part of said bottoms fraction with an aqueous metal hydroxide solution so as to provide a concentration of 0.1 to 5 wt % MOH, where M is an alkali metal, in the aqueous phase; (III) separating the aqueous phase and the organic phase; (IV) contacting at least a part the organic phase from step (III) with an aqueous metal hydroxide solution so as to provide a concentration of 6 to 20 wt % MOH in the aqueous phase; (V) separating the organic phase and aqueous phase formed in step (IV); (VI) washing at least a part of the organic phase of step (V) with water.

First claim

1 . A process comprising:
(I) distilling a crude acetone mixture containing hydrocarbons and water so as to form a bottoms fraction containing said hydrocarbons in an organic phase and an aqueous phase; (II) contacting at least a part of said bottoms fraction with an aqueous metal hydroxide solution so as to provide a concentration of 0.1 to 5 wt % MOH, where M is an alkali metal, in the aqueous phase; (III) separating the aqueous phase and the organic phase; (IV) contacting at least a part the organic phase from step (III) with an aqueous metal hydroxide solution so as to provide a concentration of 6 to 20 wt % MOH, where M is an alkali metal, in the aqueous phase; (V) separating the organic phase and aqueous phase formed in step (IV); (VI) washing at least a part of the organic phase of step (V) with water.

2 . A process as claimed in claim 1 wherein the hydrocarbons comprise cumene and alpha methyl styrene (AMS).

3 . A process as claimed in claim 1 said process comprising:
(I) distilling a crude acetone mixture obtained from the cleavage of cumene hydroperoxide and containing hydrocarbons and water so as to form a bottoms fraction containing said hydrocarbons in an organic phase and an aqueous phase;
(II) contacting said bottoms fraction with an aqueous metal hydroxide solution so as to provide a concentration of 0.1 to 5 wt % MOH, where M is an alkali metal, in the aqueous phase;
(III) separating the aqueous phase and the organic phase;
(IV) contacting the organic phase from step (III) with an aqueous metal hydroxide solution having a concentration of 6 to 20 wt % MOH, where M is an alkali metal, in the aqueous phase;
(V) separating the organic phase and aqueous phase formed in step (IV);
(VI) washing the organic phase of step (V) with water.

4 . A process as claimed in claim 1 , wherein MOH is NaOH.

5 . A process as claimed in claim 1 , wherein at least a part of the aqueous phase formed after step (VI) is used to dilute hydroxide so as to form the MOH solution required in step (IV).

6 . A process as claimed in claim 1 , wherein at least a part of the aqueous phase formed after step (IV) is diluted with water to form the hydroxide added in step (II).

7 . A process as claimed in claim 1 , wherein at least a part of the aqueous phase formed after step (II) is used to neutralise the cleavage products of an acid catalysed cumene hydroperoxide reaction.

8 . A process as claimed in claim 1 , wherein at least a part of the aqueous phase formed after step (II) is de-phenolated where the metal phenolate contained in the aqueous phase is neutralized in order to convert the phenolate to phenol, e.g. with sulphuric acid, and then stripped with steam in order to remove phenol from the aqueous phase.

9 . A process as claimed in claim 8 wherein at least a part of the aqueous phase formed after step (II) is used to neutralise the cleavage products of an acid catalysed cumene hydroperoxide reaction and wherein at least a part of the aqueous phase formed after step (II) is de-phenolated and wherein 5 to 30 wt % of the aqueous phase passes to cleavage neutralization and 70 to 95 wt % of the aqueous phase passes to dephenolation.

10 . A process as claimed in claim 1 , wherein the concentration of MOH in the aqueous phase in step (II) is about 1 wt %.

11 . A process as claimed in claim 1 , wherein the concentration of MOH in the aqueous phase in step (IV) is about 15 wt %.

12 . A process as claimed in claim 1 , wherein the temperature in at least one of steps (II), (IV) or (VI) is from 30 to 50° C.

13 . A process as claimed in claim 1 , wherein the pressure in at least one of steps (II), (IV) or (VI) is atmospheric.

14 . A dephenolation process said process comprising:
(I) distilling a crude acetone mixture containing hydrocarbons and water so as to form a bottoms fraction containing said hydrocarbons in an organic phase and an aqueous phase; (II) contacting at least a part of said bottoms fraction with an aqueous metal hydroxide solution so as to provide a concentration of 0.1 to 5 wt % MOH, where M is an alkali metal, in the aqueous phase; (III) separating the aqueous phase and the organic phase; (IV) transferring at least a part of the aqueous phase from step (III) to de-phenolation where the metal phenolate contained in the aqueous phase is neutralized in order to convert the phenolate to phenol, e.g. with sulphuric acid, and then stripped with steam in order to remove phenol from the aqueous phase.

15 . The process of claim 14 wherein the hydrocarbons in the bottoms fraction formed after step (I) comprise cumene and AMS.

16 . An apparatus comprising:
an acetone distillation column ( 1 ); a conduit ( 6 ) for carrying the bottoms fraction from column ( 1 ) to a separation vessel ( 2 ) optionally containing horizontal baffles and separation plates; a conduit ( 9 ) for adding NaOH into separation vessel ( 2 ); a conduit ( 7 ) for carrying the organic phase from vessel ( 2 ) to separation vessel ( 3 ) optionally containing horizontal baffles and separation plates; a conduit ( 10 ) for adding NaOH to separation vessel ( 3 ); a conduit ( 8 ) for carrying organic phase from vessel ( 3 ) to separation vessel ( 4 ) optionally containing horizontal baffles and separation plates; a conduit ( 12 ) for adding water to vessel ( 4 ); a conduit ( 11 ) for carrying the at least a part of the aqueous phase from vessel ( 4 ) to dilute the NaOH added via conduit ( 10 ); optionally a a conduit ( 13 ) for carrying at least a part the MOH containing aqueous phase from vessel ( 3 ) to be added to vessel ( 2 ) via conduit ( 9 ); and optionally a conduit ( 14 ) to carry at least a part of the aqueous phase from vessel ( 2 ) to neutralisation of the cleavage product from cumene hydroperoxide cleavage.

17 . An apparatus as claimed in claim 16 further comprising a conduit to carry at least a part of the aqueous phase from vessel ( 2 ) to dephenolation.

18 . A process as claimed in claim 1 , wherein the crude acetone mixture is obtained from the cleavage of cumene hydroperoxide.

19 . A process as claimed in claim 1 , wherein the temperature in all of steps (II), (IV) and (VI) is from 30 to 50° C.

20 . A process as claimed in claim 1 , wherein the pressure is atmospheric in all of steps (II), (IV) and (VI).

21 . A process as claimed in claim 14 , wherein the crude acetone mixture is obtained from the cleavage of cumene hydroperoxide.

Assignees

• Borealis Ag

Inventors

• Saukonoja Jouni
• Lindholm Tero
• Pakala Tero
• Pakala Timo

Classifications

• C07C7/10

  by extraction, i.e. purification or separation of liquid hydrocarbons with the aid of liquids · CPC title

• C07C37/08 Primary

  by decomposition of hydroperoxides, e.g. cumene hydroperoxide · CPC title

• B01D11/0492

  Applications, solvents used · CPC title

• B01D3/143 Primary

  by two or more of a fractionation, separation or rectification step · CPC title

• C07C7/04

  by distillation · CPC title