Method and System for Producing Epoxyalkane

A method for producing an epoxyalkane, the method comprises the following steps:

• 1) distilling the stream containing epoxyalkane and extractant in a separation column, obtaining the stream mainly containing epoxyalkane from the column top, and obtaining the stream mainly containing extractant from the column kettle;
• 2) dividing the stream mainly containing extractant obtained from the column kettle into at least three streams, wherein the first stream is heated by the column kettle reboiler and returned to the separation column from the column kettle;
• the second stream is used as the circulating extractant;
• the third stream is delivered to an extractant purifier for carrying out purification treatment to remove liquid phase heavy component whose boiling point is higher than that of the extractant, and obtain the vapor phase or vapor-liquid mixture treated as light component which is mainly extractant;
• 3) returning the vapor phase or vapor-liquid mixture treated as the light component which is mainly extractant to the separation column.

A method for producing an epoxyalkane, the method comprises:

• 1) sending the crude product stream containing epoxyalkane and the extractant stream to an extractive rectification column for performing extractive distillation, obtaining a stream including epoxyalkane and extractant from the column kettle;
• 2) subjecting the stream including epoxyalkane and extractant to rectification in the separation column, obtaining the stream mainly containing epoxyalkane from the column top, and obtaining the stream mainly containing extractant from the column kettle;
• 3) dividing the stream mainly containing extractant from the column kettle into at least three streams, wherein the first stream is heated by the column kettle reboiler and returned to the separation column from the column kettle;
• the second stream is used as the circulating extractant;
• the third stream is delivered to an extractant purifier for carrying out purification treatment to remove liquid phase heavy component whose boiling point is higher than that of the extractant, and obtaining the vapor phase or vapor-liquid mixture treated as light component which is mainly extractant;
• 4) returning the vapor phase or vapor-liquid mixture treated as the light component which is mainly extractant to the separation column.

An epoxyalkane production system, the system comprises:

• 1) a separation column, wherein the column kettle having an outlet being capable of leading the column kettle stream out of the separation column;
• 2) a column kettle reboiler which is arranged at the lower part of the separation column to reboil part of the kettle reboiler materials of the separation column, and return the reboiled kettle reboiler material to the separation column;
• 3) an extractant purifier which is arranged underneath the feed position of the separation column for purifying a part of the column kettle material of the separation column to remove heavy components whose boiling point is higher than that of the extractant;
• obtaining the vapor phase or vapor-liquid mixture treated as light component which is mainly an extractant and returning the light component to the separation column.

An epoxyalkane production system, the system comprises:

• 1) an extractive rectification column for performing extractive distillation of crude product stream containing epoxyalkane;
• 2) a separation column for separating the column kettle stream from the extractive rectification column, obtaining the stream mainly containing epoxyalkane from the column top, and obtaining the stream mainly containing extractant from the column kettle;
• 3) a column kettle reboiler which is arranged at the lower part of the separation column to reboil part of the column kettle materials of the separation column, and return the reboiled column kettle material to the separation column;
• 4) an extractant purifier which is arranged underneath the feed position of the separation column for receiving and purifying a part of the column kettle material of the separation column to remove heavy components whose boiling point is higher than that of the extractant;
• obtaining the vapor phase or vapor-liquid mixture treated as light component which is mainly an extractant and returning the light component to the separation column.