US-12616915-B2 - Rotary evaporator for catalyst preparation

Abstract

A rotary evaporator includes a sample flask having a reservoir for receiving a sample and a neck in communication with the reservoir. The neck extends along an axis and a purge tube extends within the neck of the sample flask along the axis. The purge tube includes a distal end and at least one opening formed in the purge tube at the distal end, the distal end being closed. Purge gas is supplied to the purge tube and injected into the sample flask via the at least one opening. The purge tube is movable along the axis via an actuator, between a retracted position, where the distal end of the purge tube is situated in the neck of the sample flask, and an extended position, where the distal end of the purge tube is situated in the reservoir of the sample flask.

Inventors

• Guanghui Zhu

Assignees

• SAUDI ARABIAN OIL COMPANY

Dates

Publication Date

20260505

Application Date

20230301

Claims (20)

1. 1 . A rotary evaporator for removing solvent from a sample, comprising: a sample flask comprising a reservoir for receiving the sample and a neck in communication with the reservoir, wherein the neck extends along an axis; a purge tube extending within the neck of the sample flask along the axis, such that a vapor channel is defined between an inner surface of the neck of the sample flask and an outer surface of the purge tube, wherein the purge tube comprises a proximal end, a distal end, a wall provided at the distal end such that the distal end is closed, an inner lumen extending along the axis between the proximal end and the distal end, and an opening formed in the outer surface of the purge tube at the distal end and in communication with the inner lumen; a purge gas source in communication with the inner lumen of the purge tube for supplying a purge gas to the inner lumen of the purge tube; a first actuator operable to rotate the sample flask about the axis; a second actuator operable to translate the purge tube along the axis between a retracted position, where the opening of the purge tube is situated in the neck of the sample flask, and an extended position, where the at least one opening of the purge tube is situated in the reservoir of the sample flask; a bath for receiving the reservoir of the sample flask and heating the sample when contained in the reservoir; and a collection flask in fluid communication with the vapor channel for receiving solvent evaporated from the sample.
2. 2 . The rotary evaporator of claim 1 , further comprising a controller operable to control movement of the purge tube between the retracted position and the extended position.
3. 3 . The rotary evaporator of claim 1 , further comprising a controller operable to control a flow rate and a temperature of the purge gas.
4. 4 . The rotary evaporator of claim 1 , further comprising a flexible tube that communicatively couples the proximal end of the purge tube to the purge gas source, wherein a first end of the flexible tube is connected to the proximal end and a second end of the flexible tube is connected to the purge gas source.
5. 5 . The rotary evaporator of claim 1 , wherein the opening formed in the purge tube comprises a plurality openings.
6. 6 . The rotary evaporator of claim 5 , wherein the plurality of openings are evenly distributed about the outer surface of the purge tube.
7. 7 . The rotary evaporator of claim 1 , further comprising a third actuator operable to move the reservoir into the bath and out of the bath, wherein the bath heats the sample contained in the reservoir when the reservoir is positioned in the bath.
8. 8 . The rotary evaporator of claim 1 , wherein the second actuator comprises a drive nut and a drive screw, the drive screw being coupled to the purge tube and extending parallel to the axis, wherein the second actuator causes rotation of the drive nut, and rotation of the drive nut translates the drive screw and the purge tube in a first direction or a second direction opposite the first direction.
9. 9 . The rotary evaporator of claim 1 , wherein the outer surface of the purge tube comprises a thread and the second actuator comprises a drive nut operatively arranged around the thread of the purge tube, and wherein the second actuator causes rotation of the drive nut, and rotation of the drive nut translates the purge tube in a first direction or a second direction opposite the first direction along the axis.
10. 10 . The rotary evaporator of claim 1 , wherein the outer surface of the purge tube comprises a rack gear and the second actuator comprises a pinion gear engaging the rack gear of the purge tube, and wherein the second actuator causes rotation of the pinion gear, and rotation of the pinion gear translates the purge tube in a first direction or a second direction opposite the first direction along the axis.
11. 11 . The rotary evaporator of claim 1 , further comprising: a third actuator operable to move the reservoir into the bath and out of the bath, wherein the bath heats the sample contained in the reservoir when the reservoir is positioned in the bath; and a controller, wherein: the controller is operable to control the third actuator and thereby cause movement of the sample flask into and out of the bath; the controller is operable to control the first actuator and thereby cause rotation of the sample flask about the axis; and the controller is operable to control the second actuator and thereby cause movement of the purge tube between the retracted position and the extended position.
12. 12 . The rotary evaporator of claim 11 , wherein the controller operable to control a flow rate and a temperature of the purge gas.
13. 13 . A method for evaporating a solvent from a sample, comprising: placing the sample in a reservoir of a sample flask, wherein the sample flask comprises a neck that extends along an axis and is in communication with the reservoir; heating the reservoir of the sample flask in a bath; rotating the sample flask around the axis by a first actuator during the heating; supplying a purge gas from a purge gas source to a purge tube, wherein: the purge tube extends within the neck of the sample flask along the axis, such that a vapor channel is defined between an inner surface of the neck and an outer surface of the purge tube, the purge tube comprises a proximal end, a distal end, a wall provided at the distal end such that the distal end is closed, an inner lumen extending along the axis between the proximal end and the distal end, and an opening formed in the outer surface of the purge tube at the distal end of the purge tube and in communication with the inner lumen, and the purge gas source is in communication with the inner lumen of the purge tube; injecting the purge gas into the sample flask via the at least one opening formed in the outer surface of the purge tube; adjusting a position of the purge tube along the axis via a second actuator, wherein the second actuator is operable to translate the purge tube along the axis between a retracted position, where the at least one opening of the purge tube is situated in the neck of the sample flask, and an extended position, where the at least one opening of the purge tube is situated in the reservoir of the sample flask; guiding vapor formed by the heating through the vapor channel into a condenser where the vapor is condensed into the solvent; and receiving the solvent in a collection flask that is in fluid communication with the condenser.
14. 14 . The method of claim 13 , wherein the position of the purge tube is adjusted along the axis via the second actuator by adjusting a distance at which the purge tube extends into the sample flask before the solvent is evaporated by the heating.
15. 15 . The method of claim 13 , wherein the position of the purge tube is adjusted along the axis via the second actuator by positioning the at least one opening of the purge tube within the neck of the sample flask during an initial stage of the heating, and moving the purge tube into the extended position, such that the at least one opening of the purge tube is positioned within the reservoir, at a later stage of the heating.
16. 16 . The method of claim 13 , further comprising adjusting a flow rate of the purge gas.
17. 17 . The method of claim 13 , further comprising adjusting a temperature of the purge gas.
18. 18 . The method of claim 13 , further comprising adjusting a flow rate and a temperature of the purge gas.
19. 19 . The method of claim 18 , further comprising adjusting the flow rate and the temperature of the purge gas before evaporation is caused by the heating.
20. 20 . The method of claim 18 , further comprising adjusting the flow rate and the temperature of the purge gas after evaporation is caused by the heating.

Description

FIELD The present disclosure relates to catalyst preparation and, more specifically, to rotary evaporator apparatuses. BACKGROUND Wet impregnation is a common method for adding a metal onto a catalyst support. After introducing metal solution to the catalyst support, the liquid is evaporated and the metal deposits onto the catalyst support. During wet impregnation, the drying rate of the metal solution is critical to make a highly efficient catalyst. A rotary evaporator is an apparatus that is commonly used for the evaporation process. With regard to commercially available rotary evaporators, the evaporation rate may be controlled by adjusting the flask pressure or adjusting the temperature. However, adjusting pressure and temperature in this manner may result in water condensation and backflow, which reduces the evaporation quality. In particular, water vapor from the flask tends to condensate on the neck because the temperature of the neck is lower than the metal solution which sits inside a heat bath, water droplets from condensation will flow back to the flask and wet the catalyst, and wetted catalyst pellets tend to stay on the flask wall and cause non-uniform evaporation. Accordingly, a need exists for an improved rotary evaporator. BRIEF SUMMARY According to one or more aspects of the present disclosure, a rotary evaporator may include a sample flask having a reservoir for receiving the sample and a neck in communication with the reservoir, wherein the neck extends along an axis. The rotary evaporator may also include a purge tube extending within the neck of the sample flask along the axis, such that a vapor channel is defined between an inner surface of the neck of the sample flask and an outer surface of the purge tube. The purge tube may include a proximal end, a distal end, a wall provided at the distal end such that the distal end is closed, an inner lumen extending along the axis between the proximal end and the distal end, and an opening formed in the outer surface of the purge tube at the distal end and in communication with the inner lumen. The rotary evaporator may also include a purge gas source in communication with the inner lumen of the purge tube for supplying a purge gas to the inner lumen of the purge tube. The rotary evaporator may also include a first actuator operable to rotate the sample flask about the axis, and a second actuator operable to translate the purge tube along the axis between a retracted position, where the opening of the purge tube is situated in the neck of the sample flask, and an extended position, where the at least one opening of the purge tube is situated in the reservoir of the sample flask. The rotary evaporator may also include a bath for receiving the reservoir of the sample flask and heating the sample when contained in the reservoir, and a collection flask in fluid communication with the vapor channel for receiving solvent evaporated from the sample. According to one or more other aspects of the present disclosure, a method for evaporating a solvent from a sample may include placing the sample in a reservoir of a sample flask, wherein the sample flask comprises a neck that extends along an axis and is in communication with the reservoir; heating the reservoir of the sample flask in a bath. The method may also include rotating the sample flask around the axis by a first actuator during the heating, and supplying a purge gas from a purge gas source to a purge tube. The purge tube may extend within the neck of the sample flask along the axis, such that a vapor channel is defined between an inner surface of the neck and an outer surface of the purge tube. The purge tube may include a proximal end, a distal end, a wall provided at the distal end such that the distal end is closed, an inner lumen extending along the axis between the proximal end and the distal end, and an opening formed in the outer surface of the purge tube at the distal end of the purge tube and in communication with the inner lumen, and the purge gas source is in communication with the inner lumen of the purge tube. The method may also include injecting the purge gas into the sample flask via the at least one opening formed in the outer surface of the purge tube, and adjusting a position of the purge tube along the axis via a second actuator. The second actuator may be operable to translate the purge tube along the axis between a retracted position, where the at least one opening of the purge tube is situated in the neck of the sample flask, and an extended position, where the at least one opening of the purge tube is situated in the reservoir of the sample flask. The method may also include guiding vapor formed by the heating through the vapor channel into a condenser where the vapor is condensed into the solvent, and receiving the solvent in a collection flask that is in fluid communication with the condenser. Additional features and advantages of the technology described in this disclo