Integrated process for making propene oxide and an alkyl tert-butyl ether

1. An integrated process for making propene oxide and an alkyl tert-butyl ether, comprising:

a) a step of dehydrogenating a feed stream S1 comprising iso-butane, to provide a stream, S2, comprising iso-butene and hydrogen;

b) a separation step separating stream S2 into a stream, S3, consisting essentially of hydrogen and a stream, S4, comprising iso-butene;

c) a step of reacting a part or all of stream S4 with an alkanol in the presence of a solid acid catalyst, to provide a stream, S5, comprising an alkyl tert-butyl ether;

d) a separation step separating the alkyl tert-butyl ether from stream S5;

e) a step of reacting a part or all of stream S3 with oxygen, to provide a stream, S6, comprising hydrogen peroxide;

f) a step of reacting a part or all of stream S6 with propene in the presence of an epoxidation catalyst, to provide a stream, S7, comprising propene oxide; and

g) a separation step separating propene oxide from stream S7.

2. The process of claim 1 , wherein the alkanol is methanol.

3. The process of claim 1 , wherein a stream, S8, comprising unreacted iso-butane is separated in step d), a stream S9 comprising more than 80% by weight iso-butane is separated from stream S8 and stream S9 is recycled to step a).

4. The process of claim 1 , wherein the feed stream S1 of step a) comprises n-butane, a stream, S8, comprising 1-butene is separated in step d) and a stream, S10, consisting essentially of 1-butene is separated from said stream S8.

5. The process of claim 1 , wherein the feed stream S1 to step a) comprises n-butane and wherein 1,3-butadiene is removed from stream S4 before reacting it in step c).

6. The process of claim 1 , comprising an additional step of isomerizing n-butane to iso-butane, to provide the feed stream S1 to step a).

7. The process of claim 1 , wherein step e) is carried out as an anthraquinone process providing a 20 to 75% by weight aqueous solution of hydrogen peroxide as stream S6.

8. The process of claim 1 , wherein a titanium silicalite catalyst is used as epoxidation catalyst in step f).

9. The process of claim 1 , wherein additional hydrogen is fed to step e).

10. An integrated process for making propene oxide and methyl tert-butyl ether, comprising:

a) a step of dehydrogenating a feed stream, S1, comprising iso-butane, to provide a stream, S2, comprising iso-butene and hydrogen;

b) a separation step separating stream S2 into a stream, S3, consisting essentially of hydrogen and a stream, S4, comprising iso-butene;

c) a step of reacting a part or all of stream S4 with methanol in the presence of a solid acid catalyst, to provide a stream, S5, comprising methyl tert-butyl ether;

d) a separation step separating methyl tert-butyl ether from stream S5;

e) a step of reacting a part or all of stream S3 with oxygen in an anthraquinone process, to provide a stream, S6, comprising hydrogen peroxide as a 20 to 75% by weight aqueous solution of hydrogen peroxide;

f) a step of reacting a part or all of stream S6 with propene in the presence of an epoxidation catalyst, to provide a stream, S7, comprising propene oxide; and

g) a separation step separating propene oxide from stream S7.

11. The process of claim 10 , wherein a titanium silicalite catalyst is used as epoxidation catalyst in step f).

12. The process of claim 10 , wherein the feed stream S1 to step a) comprises n-butane, a stream, S8, comprising 1-butene is separated in step d) and a stream, S10, consisting essentially of 1-butene is separated from said stream S8.

13. The process of claim 12 , wherein 1,3-butadiene is removed from stream S4 before reacting it in step c).