WO2020021354A1

WO2020021354A1 - Process for preparation of glycolaldehyde from formaldehyde

Info

Publication number: WO2020021354A1
Application number: PCT/IB2019/055067
Authority: WO
Inventors: Uma K SANKAR; Makarand DIWAKAR; Raj Deshpande
Original assignee: Sabic Global Technologies B.V.
Priority date: 2018-07-23
Filing date: 2019-06-17
Publication date: 2020-01-30

Abstract

A method of producing glycolaldehyde by the hydroformylation of formaldehyde in the presence of a solvent and a catalyst. A reaction mixture formed by the hydroformylation is contacted with a mixture of dichloromethane and water to aid in the extraction of glycolaldehyde from the reaction mixture.

Description

PROCESS FOR PREPARATION OF GLYCOLALDEHYDE FROM

FORMALDEHYDE

CROSS REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of priority to U.S. Provisional Patent Application No. 62/702,217, filed July 23, 2018, the entire contents of which are hereby incorporated by reference in their entirety.

FIELD OF INVENTION

[0002] The present invention generally relates to a method of producing glycolaldehyde. More specifically, the present invention relates to a method of hydroformylating formaldehyde to produce glycolaldehyde and recovering the glycolaldehyde from the mixture resulting from the hydroformylation reaction.

BACKGROUND OF THE INVENTION

[0003] Glycolaldehyde (HOCH₂-CHO) is an organic compound that is a very useful building block for other commercial chemicals. For example, glycolaldehyde is used to produce ethylene glycol, a chemical used in coolant and antifreeze. Glycolaldehyde is typically produced by hydroformylation of formaldehyde, where the formaldehyde is reacted with carbon monoxide and hydrogen in the presence of an appropriate catalyst. A catalyst that is often used in the hydroformylation reaction is a rhodium-ligand complex. Generally, the hydroformylation reaction is carried out in a solvent capable of dissolving polar material. Examples of such solvents are amides, such as N,N-dimethylacetamide.

[0004] The production of glycolaldehyde by hydroformylation is challenging because it is difficult to remove the glycolaldehyde product from the reaction mixture. This is so because typical separation methods involve distilling, in which heat is applied to take advantage of the different boiling points of the components in order to effect separation. Distillation, however, has certain disadvantages with respect to glycolaldehyde and the reaction mixture. Distillation at high temperatures or at low pressures can deactivate/destabilize the catalyst-ligand complex. Additionally, because the hydroformylation solvent employed is polar, it is difficult to separate it from the glycolaldehyde. [0005] Different types of separation processes have been attempted. For example, one process involves using a polar low boiling solvent like acetonitrile for facilitating hydroformylation and a non-polar high boiling solvent like xylene to recover the catalyst from the distillation bottoms. Another process is known for using a polar low boiling point solvent like acetonitrile for facilitating hydroformylation, a non-polar high boiling solvent like xylene to recover catalyst, and a non-polar low boiling solvent like diethyl ether to enhance catalyst separation. Other processes involve the separation of glycolaldehyde from formaldehyde via vacuum distillation and recovery of catalyst from the residue. Further, some processes involve aqueous extraction of glycolaldehyde from the hydroformylation product mixture.

[0006] In sum, conventional methods provide for the use of two or more solvent combinations for the recovery of the product and for catalyst recycle and also describes use of one or more distillation operations to recover catalyst from glycolaldehyde.

BRIEF SUMMARY OF THE INVENTION

[0007] A method has been discovered for the production of glycolaldehyde that involves hydroformylation of formaldehyde. In a reactor, a mixture of an amide solvent and formaldehyde reacts with carbon monoxide and hydrogen in the presence of an appropriate catalyst. The catalyst, according to embodiments of the invention, is a water immiscible rhodium-phosphine based catalyst. The reactor effluent is treated with an extractant— a mixture of dichloromethane and water— so that glycolaldehyde partitions to an aqueous phase and catalyst with amide solvent remains in an organic phase. The organic phase is flashed to remove dichloromethane and the catalyst residue is recycled to the reactor. The use of dichloromethane in this manner in the production of glycolaldehyde provides the benefit of separation of glycolaldehyde and the reaction solvent along with the catalyst.

[0008] Embodiments of the invention include a method of producing glycolaldehyde that includes hydroformylating, in a reactor, formaldehyde in presence of an amide solvent and a catalyst to form the glycolaldehyde and flowing a reactor effluent comprising the glycolaldehyde, the catalyst, and the amide solvent from the reactor. The method further includes contacting at least a portion of the reactor effluent with a solvent mixture that comprises water and dichloromethane and thereby produce an intermediate liquid product stream having (a) an aqueous phase comprising at least some of the glycolaldehyde and (b) an organic phase comprising the catalyst.

[0009] Embodiments of the invention include a method of producing glycolaldehyde that includes disposing formaldehyde, carbon monoxide, hydrogen, N,N-dimethylacetamide (dimethylacetamide) and a catalyst in a reactor and subjecting a mixture of the formaldehyde, the carbon monoxide, the hydrogen, the dimethylacetamide, and the catalyst in the reactor under reaction conditions sufficient to form the glycolaldehyde. The method further includes flowing a reactor effluent comprising the glycolaldehyde, the catalyst, and the dimethylacetamide from the reactor and flashing the reactor effluent to produce a gas effluent stream and a liquid effluent stream. The method further yet includes contacting the liquid effluent stream with a solvent mixture that comprises water and dichloromethane to thereby produce an intermediate liquid product stream having (a) an aqueous phase comprising at least some of the glycolaldehyde and (b) an organic phase comprising the amide solvent and the catalyst and separating the intermediate product stream in a separation unit comprising two decanters and a flashing unit to produce an aqueous product stream comprising primarily water and dichloromethane, collectively and an organic product stream comprising primarily the dimethylacetamide and catalyst, collectively.

[0010] The following includes definitions of various terms and phrases used throughout this specification. [0011] The terms “about” or“approximately” are defined as being close to as understood by one of ordinary skill in the art. In one non-limiting embodiment the terms are defined to be within 10%, preferably, within 5%, more preferably, within 1%, and most preferably, within 0.5%.

[0012] The terms“wt. %,”“vol. %” or“mol. %” refers to a weight, volume, or molar percentage of a component, respectively, based on the total weight, the total volume, or the total moles of material that includes the component. In a non-limiting example, 10 moles of component in 100 moles of the material is 10 mol. % of component.

[0013] The term“substantially” and its variations are defined to include ranges within

10%, within 5%, within 1%, or within 0.5%. [0014] The terms“inhibiting” or“reducing” or“preventing” or“avoiding” or any variation of these terms, when used in the claims and/or the specification, include any measurable decrease or complete inhibition to achieve a desired result.

[0015] The term“effective,” as that term is used in the specification and/or claims, means adequate to accomplish a desired, expected, or intended result.

[0016] The use of the words“a” or“an” when used in conjunction with the term

“comprising,”“including,”“containing,” or“having” in the claims or the specification may mean“one,” but it is also consistent with the meaning of“one or more,”“at least one,” and “one or more than one.”

[0017] The words“comprising” (and any form of comprising, such as“comprise” and

“comprises”),“having” (and any form of having, such as“have” and“has”),“including” (and any form of including, such as“includes” and“include”) or“containing” (and any form of containing, such as“contains” and“contain”) are inclusive or open-ended and do not exclude additional, unrecited elements or method steps.

[0018] The process of the present invention can“comprise,”“consist essentially of,” or“consist of’ particular ingredients, components, compositions, etc., disclosed throughout the specification.

[0019] The term“primarily,” as that term is used in the specification and/or claims, means greater than any of 50 wt. %, 50 mol. %, and 50 vol. %. For example,“primarily” may include 50.1 wt. % to 100 wt. % and all values and ranges there between, 50.1 mol. % to 100 mol. % and all values and ranges there between, or 50.1 vol. % to 100 vol. % and all values and ranges there between.

[0020] Other objects, features and advantages of the present invention will become apparent from the following figures, detailed description, and examples. It should be understood, however, that the figures, detailed description, and examples, while indicating specific embodiments of the invention, are given by way of illustration only and are not meant to be limiting. Additionally, it is contemplated that changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description. In further embodiments, features from specific embodiments may be combined with features from other embodiments. For example, features from one embodiment may be combined with features from any of the other embodiments. In further embodiments, additional features may be added to the specific embodiments described herein.

BRIEF DESCRIPTION OF THE DRAWINGS [0021] For a more complete understanding, reference is now made to the following descriptions taken in conjunction with the accompanying drawings, in which:

[0022] FIG. l is a system for producing glycolaldehyde, according to embodiments of the invention;

[0023] FIG. 2 is a method for producing glycolaldehyde, according to embodiments of the invention; and

[0024] FIG. 3 shows quantities of various materials annotated on the system of FIG.

1, based on an experimental example, according to embodiments of the invention.

DETAILED DESCRIPTION OF THE INVENTION

[0025] A method has been discovered for the production of glycolaldehyde that involves reacting formaldehyde, carbon monoxide, and hydrogen, in a reactor in the presence of a catalyst, where the formaldehyde is dissolved in an amide solvent. A mixture resulting from the reaction is treated with an extractant— a mixture of dichloromethane and water such that the majority of the glycolaldehyde is held in an aqueous phase and the majority of the catalyst with amide solvent is retained in an organic phase. The use of dichloromethane in this manner in the production of glycolaldehyde provides the benefit of separation of glycolaldehyde and the amide reaction solvent along with the catalyst.

[0026] FIG. 1 shows system 10 for producing glycolaldehyde, according to embodiments of the invention. FIG. 2 shows method 20 for producing glycolaldehyde, according to embodiments of the invention. Method 20 may be implemented using system 10.

[0027] According to embodiments of the invention, method 20, as implemented by system 10, involves, at block 200, the hydroformylation of formaldehyde in the presence of an amide solvent ( e.g ., N, A-Dimethyl acetamide) and a catalyst (e.g, RhClCO(PPh₃)₂, [Rh(COD)Cl]₂, Rh(CO)₂(acac), HRh(CO)PPh₃)₃, [Rh(CO)₂Cl]₂, and other complexes of rhodium) to form the glycolaldehyde. The hydroformylation reaction can be carried out by flowing the formaldehyde, carbon monoxide, hydrogen, amide solvent, and the catalyst in a hydroformylation reactor, reactor 101 and subjecting a mixture of the formaldehyde, the carbon monoxide, the hydrogen, the dimethylacetamide, and the catalyst in the reactor under reaction conditions sufficient to form the glycolaldehyde. The reaction conditions provided in reactor 101 to effect the hydroformylation, according to embodiments of the invention, can include a temperature of 90 to 120 °C and all ranges and values there between including ranges of 90 to 95 °C, 95 to 100 °C, 100 to 105 °C, 105 to 110 °C, 110 to 115 °C and 115 to 120 °C, and a pressure of 800 to 1200 psi and all ranges and values there between including ranges of 800 to 850 psi, 850 to 900 psi, 900 to 950 psi, 950 to 1000 psi, 1000 to 1050 psi, 1050 to 1100 psi, 1100 to 1150 psi and 1150 to 1200 psi. According to embodiments of the invention, the hydroformylation reaction is carried out as a single phase reaction (in the liquid phase).

[0028] After conversion of at least some of the formaldehyde to glycolaldehyde, method 20, at block 201, may include flowing reactor effluent 102 from reactor 101 to flasher 103. Reactor effluent 102, according to embodiments of the invention, comprises 1 to 25 wt. % glycolaldehyde, 50 to 90 wt. % amide solvent, 0.1 to 15 wt. % methanol, 0.1 to 15 wt. % formaldehyde, 0.1 to 1 wt. % catalyst, 1 to 10 wt. % carbon monoxide, 1 to 10 wt.% hydrogen.

[0029] In embodiments of the invention, reactor effluent 102 is separated into a gas portion and a liquid portion, at block 202 of method 20. As shown in FIG. 1, reactor effluent 102 can be separated by a flash vessel, flasher 103, to produce gas effluent stream 104 and liquid effluent stream 105. Thus, reactor effluent 102, which includes dimethylacetamide (DMAc), glycolaldehyde (GA), methanol (MeOH), formaldehyde (HCHO), catalyst (cat), CO, and H₂ are flashed to remove the gases and depressurized to room temperature. The conditions in flasher 103 sufficient to effect the separation of reactor effluent 102 and form gas effluent stream 104 and liquid effluent stream 105 include a temperature of 30 to 120 °C and all ranges and values there between including ranges of 30 to 35 °C, 35 to 40 °C, 40 to 45 °C, 45 to 50 °C, 50 to 55 °C, 55 to 60 °C, 60 to 65 °C, 65 to 70 °C, 70 to 75 °C, 75 to 80 °C, 80 to 85 °C, 85 to 90 °C, 90 to 95 °C, 95 to 100 °C, 100 to 105 °C, 105 to 110 °C, 110 to 115 °C and 115 to 120 °C, and a pressure of 0 to 500 psi and all ranges and values there between including ranges of 0 to 50 psi, 50 to 100 psi, 100 to 150 psi, 150 to 200 psi, 200 to 250 psi, 250 to 300 psi, 300 to 350 psi, 350 to 400 psi, 400 to 450 psi and 450 to 500 psi, in embodiments of the invention. Gas effluent stream 104, according to embodiments of the invention, comprises 1 to 15 wt. % formaldehyde, 1 to 50 wt. % carbon monoxide, and 1 to 50 wt.% hydrogen. Liquid effluent stream 105, according to embodiments of the invention comprises 1 to 25 wt. % glycolaldehyde in solution with 70 to 99 wt. % amide solvent.

[0030] According to embodiments of the invention, solvent mixture 106, which is a mixture of water and dichloromethane (an extractant) is added to liquid effluent stream 105, at block 203 of method 20. According to embodiments of the invention, solvent mixture 106 comprises 65 to 75 wt.% dichloromethane and 25 to 35 wt.% water. In this way, the weight ratio of amide solvent:dichloromethane:water in intermediate liquid product stream 107 is (5 to 20):(20 to 30):(5 to 15), preferably about 15:25: 10. As shown in FIG. 1, the mixing may be carried out by mixer 119, which produces intermediate liquid product stream 107. Intermediate liquid product stream 107, having been formed by mixing liquid effluent stream 105 with solvent mixture 106, comprises two phases. The formation of the phases is aided by the addition of solvent mixture 106 mixed to liquid effluent stream 105. Intermediate liquid product stream 107 has at least some of the glycolaldehyde produced by the hydroformylation of block 200 in an aqueous phase and, the catalyst and the amide solvent are included in an organic phase. Intermediate liquid product stream 107 is separated, in embodiments of the invention, into an aqueous phase and an organic phase, at block 204.

[0031] Block 204, according to embodiments of the invention, may involve one or more settling and flashing processes. As illustrated in FIG. 1, intermediate liquid product stream 107 may be separated by separation unit 120, which includes decanter 108 and decanter 111 for carrying out the settling operations and flasher 116 for carrying out the flashing process. According to embodiments of the invention, separation unit 120 separates intermediate liquid product stream 107 to produce aqueous product stream 113 and organic product stream 118.

[0032] In operation, separation unit 120, in embodiments of the invention, receives, settles, and separates intermediate liquid product stream 107 at decanter 108 to produce (A) aqueous layer stream 109, which can comprise 4 wt. % to 10 wt. % glycolaldehyde, 5 wt. % to 7 wt. % dichloromethane, 20 wt. % to 30 wt. % amide solvent and 47 wt. % to 71 wt. % water and (B) organic layer stream 110, which can comprise 70 wt. % to 90 wt. % dichloromethane, 15 wt. % to 25 wt. % amide solvent, more than 99 wt. % of the catalyst that was present in the reactor, and 4 wt. % to 6 wt. % water.

[0033] According to embodiments of the invention, organic layer stream 110 is flowed to flasher 116, where organic layer stream 110 is flashed to produce gas stream 117 and organic product stream 118. Gas stream 117, which, in embodiments of the invention, comprises dichloromethane and water, is recovered as distillate from flasher 116 and can be reused for extraction. Organic product stream 118, in embodiments of the invention, comprises 15 to 25 wt. % dichloromethane, 55 to 80 wt. % amide solvent, 2 to 4 wt. % glycolaldehyde, 3 to 7 wt. % water, and more than 99 wt. % of the catalyst that was present in the reactor. Organic product stream 118, which can comprise amide solvent and catalyst, in embodiments of the invention, can be recycled to reactor 101 to contribute to the hydroformylation reaction.

[0034] Aqueous layer stream 109, in the meantime may be flowed to a second decanter, decanter 111, as shown in FIG. 1. According to embodiments of the invention, additional dichloromethane may be added to aqueous layer stream 109 in decanter 111 to aid in the further extraction of glycolaldehyde. In embodiments of the invention, decanter 111 receives aqueous layer stream 109 and dichloromethane stream 112 and separates the mixture of these streams into (I) aqueous product stream 113 comprising 50 to 90 wt. % water, 5 to 30 wt. % amide solvent, 95 to 99.9 wt. % catalyst and (II) organic recycle stream 114, comprising 70 to 90 wt. % dichloromethane, 1 to 20 wt. % amide solvent, 1 to 4 wt. % glycolaldehyde, 2 to 6 wt. % water. Organic recycle stream 114, according to embodiments of the invention, is routed to flasher 116, by a combining it with organic layer stream 110 to form combined stream 115. Combined stream 115 is then fed to flasher 116.

[0035] Aqueous product stream 113, after extraction in decanter 111, comprises glycolaldehyde of a quality that can be routed to other processing units for further processing to produce other products such as ethylene glycol.

[0036] Although embodiments of the present invention have been described with reference to blocks of FIG. 2, it should be appreciated that operation of the present invention is not limited to the particular blocks and/or the particular order of the blocks illustrated in FIG. 2. Accordingly, embodiments of the invention may provide functionality as described herein using various blocks in a sequence different than that of FIG. 2. EXAMPLES

Example 1

(Production of glycolaldehyde with the use of dichloromethane as an extractant)

[0037] As part of the disclosure of the present invention, a specific example is included below. The example is for illustrative purposes only and is not intended to limit the invention. Those of ordinary skill in the art will readily recognize parameters that can be changed or modified to yield essentially the same results.

[0038] Example 1 is an experiment carried out to show the effectiveness of embodiments of the invention. A 300 ml PARR reactor was charged with 96.3 g N N- Dimethylacetamide (DMAc), 0.458 g RhClCO(PPh₃)2 and 5.01 g /¾/ra-form al dehy de. The reaction was conducted at 110 °C with 900 psi of 1 : 1 CO:H₂ gas for 3 hours. The reaction showed 6.3% glycolaldehyde (GA) productivity (6.41 g GA/total weight) with 95% selectivity towards GA. To the depressurized reaction product 158 g dichloromethane (DCM) and 63.2 g water were added in a weight ratio of DMAc:DCM:water=l5:25: lO. The mixture splits to an aqueous and an organic phase. The organic phase weighing 202.8 g was subjected to flashing at 70 °C with 50 ml/min N₂ for two hours. The aqueous layer weighing 111.5 g was re-extracted with DCM 139.7 g DCM (ratio of aqueous layer:DCM=l : l.5). The organic layer after the second extraction was flashed at 70 °C with 50 ml/min N₂ for two hours. 99.9% catalyst was recycled in the mixed residue. The residues from both the flashings were mixed and the composition of the stream was as follows: DMAc=74%, water=6%, DCM=l4%, GA=2.6%. 71.1 g of this mixed residue is hydroformylated (at 110 °C, 900 psi of 1 : 1 CO:H₂ gas) by adding 3.75 g /¾/ra-formal dehy de . The reaction showed GA productivity of 4.3% with a selectivity of 79%.

[0039] In the context of the present invention, embodiments 1-18 are described.

Embodiment 1 is a method of producing glycolaldehyde. The method includes hydroformylating, in a reactor, formaldehyde in presence of an amide solvent and a catalyst to form the glycolaldehyde. The method further includes flowing a reactor effluent containing the glycolaldehyde, the catalyst, and the amide solvent from the reactor, and contacting at least a portion of the reactor effluent with a solvent mixture that includes water and dichloromethane and thereby producing an intermediate liquid product stream having (a) an aqueous phase including at least some of the glycolaldehyde and (b) an organic phase comprising the catalyst. Embodiment 2 is the method of embodiment 1, wherein the organic phase further includes the amide solvent. Embodiment 3 is the method of either of embodiments 1 or 2 further including flowing the formaldehyde, the amide solvent, carbon monoxide, and hydrogen to the reactor, in which the catalyst is disposed, to carry out the hydroformylation. Embodiment 4 is the method of any of embodiments 1 to 3 wherein reaction conditions for the hydroformylation include a temperature of 90 to 120 °C and a pressure of 800 to 1200 psi. Embodiment 5 is the method of any of embodiments 1 to 4 wherein the reactor effluent includes 1 to 25 wt. % glycolaldehyde, 50 to 90 wt. % amide solvent, 0.1 to 15 wt. % methanol, 0.1 to 15 wt. % formaldehyde, 0.1 to 0.5 wt. % catalyst, 1 to 50 wt. % carbon monoxide, 1 to 50 wt.% hydrogen. Embodiment 6 is the method of any of embodiments 1 to 5, further including flashing the reactor effluent, in a first flash vessel, to produce a gas effluent stream and a liquid effluent stream, wherein the portion of the reactor effluent contacted with the solvent mixture includes the liquid effluent stream. Embodiment 7 is the method of embodiment 6, wherein the gas effluent stream includes 1 to 15 wt. % formaldehyde, 1 to 50 wt. % carbon monoxide, 1 to 50 wt. % hydrogen. Embodiment 8 is the method of either of embodiments 6 or 7, wherein the liquid effluent stream includes 1 to 25 wt. % glycolaldehyde, 50 to 90 wt. % amide solvent, 0.1 to 15 wt. % methanol, 0.1 to 0.5 wt. % catalyst. Embodiment 9 is the method of any of embodiments 1 to 8, further including separating the intermediate liquid product stream in a separation unit that includes one or more decanters to produce an aqueous product stream and an organic product stream. Embodiment 10 is the method of embodiment 9, wherein the separating of the intermediate liquid product stream in the separation unit includes adding dichloromethane to material disposed in the one or more decanters. Embodiment 11 is the method of either of embodiments 9 or 10, wherein a first decanter of the one or more decanters receives and separates the intermediate liquid product stream to produce an aqueous layer stream that includes 4 wt. % to 10 wt. % glycolaldehyde, 5 wt. % to 7 wt. % dichloromethane, 20 wt. % to 30 wt. % amide solvent, and 47 wt. % to 71 wt. % water. Embodiment 12 is the method of embodiment 11, wherein the method further includes flowing the aqueous layer stream to a second decanter of the one or more decanters and separating the aqueous layer stream into an aqueous product stream including 50 to 90 wt. % water, 5 to 30 wt. % amide solvent, 0.1 to 0.5 wt. % catalyst and an organic product stream including 70 to 90 wt. % dichloromethane, 10 to 30 wt. % amide solvent, 1 to 4 wt. % glycolaldehyde, 4 to 6 wt. % water. Embodiment 13 is the method of either of embodiments 11 or 12, wherein the first decanter of the one or more decanters produces an organic layer stream that includes 70 wt. % to 90 wt. % dichloromethane, 15 wt. % to 25 wt. % amide solvent, more than 99 wt. % of the catalyst that was present in the reactor, and 4 wt. % to 6 wt. % water. Embodiment 14 is the method of embodiment 13, further including flowing the organic layer stream to a second flash vessel included in the separation unit and flashing the organic layer stream to produce (1) a gas stream including dichloromethane and water and (2) the organic product stream including the amide solvent and at least some of the catalyst. Embodiment 15 is the method of any of embodiments 12 to 14, further including recycling the organic product stream to the reactor. Embodiment 16 is the method of any of embodiments 1 to 15, wherein the amide solvent includes dimethylacetamide. Embodiment 17 is the method of any of embodiments 1 to 16, wherein the catalyst includes ( e.g ., RhClCO(PPh₃)₂, [Rh(COD)Cl]₂, Rh(CO)₂(acac), HRh(CO(PPh₃)₃, [Rh(CO)₂Cl]₂, and other complexes of rhodium). Embodiment 18 is the method of any of embodiments 1 to 17, wherein a weight ratio of amide solvent:dichloromethane:water in the intermediate liquid product stream is (5 to 20): (20 to 30): (5 to 15).

[0040] Although embodiments of the present application and their advantages have been described in detail, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the embodiments as defined by the appended claims. Moreover, the scope of the present application is not intended to be limited to the particular embodiments of the process, machine, manufacture, composition of matter, means, methods and steps described in the specification. As one of ordinary skill in the art will readily appreciate from the above disclosure, processes, machines, manufacture, compositions of matter, means, methods, or steps, presently existing or later to be developed that perform substantially the same function or achieve substantially the same result as the corresponding embodiments described herein may be utilized. Accordingly, the appended claims are intended to include within their scope such processes, machines, manufacture, compositions of matter, means, methods, or steps.

Claims

CLAIMS What is claimed is:

1. A method of producing glycolaldehyde, the method comprising:

hydroformylating, in a reactor, formaldehyde in presence of an amide solvent and a catalyst to form the glycolaldehyde; flowing a reactor effluent comprising the glycolaldehyde, the catalyst, and the amide solvent from the reactor; and contacting at least a portion of the reactor effluent with a solvent mixture that comprises water and dichloromethane and thereby producing an intermediate liquid product stream having (a) an aqueous phase comprising at least some of the glycolaldehyde and (b) an organic phase comprising the catalyst.

2. The method of claim 1, wherein the organic phase further comprises the amide solvent.

3. The method of any of claims 1 and 2 further comprising:

flowing the formaldehyde, the amide solvent, carbon monoxide, and hydrogen to the reactor, in which the catalyst is disposed, to carry out the hydroformylation.

4. The method of any of claims 1 to 2 wherein reaction conditions for the hydroformylation comprise a temperature of 90 to 120 °C and a pressure of 800 to 1200 psi.

5. The method of any of claims 1 to 2 wherein the reactor effluent comprises 1 to 25 wt.

% glycolaldehyde, 50 to 90 wt. % amide solvent, 0.1 to 15 wt. % methanol, 0.1 to 15 wt. % formaldehyde, 0.1 to 0.5 wt. % catalyst, 1 to 50 wt. % carbon monoxide, 1 to 50 wt.% hydrogen.

6. The method of any of claims 1 to 2, further comprising:

flashing the reactor effluent, in a first flash vessel, to produce a gas effluent stream and a liquid effluent stream, wherein the portion of the reactor effluent contacted with the solvent mixture comprises the liquid effluent stream.

7. The method of claim 6, wherein the gas effluent stream comprises 1 to 15 wt. % formaldehyde, 1 to 50 wt. % carbon monoxide, 1 to 50 wt. % hydrogen.

8. The method of claim 6, wherein the liquid effluent stream comprises 1 to 25 wt. % glycolaldehyde, 50 to 90 wt. % amide solvent, 0.1 to 15 wt. % methanol, 0.1 to 0.5 wt. % catalyst.

9. The method of any of claims 1 to 2, further comprising:

separating the intermediate liquid product stream in a separation unit that comprises one or more decanters to produce an aqueous product stream and an organic product stream.

10. The method of claim 9, wherein the separating of the intermediate liquid product stream in the separation unit comprises adding dichloromethane to material disposed in the one or more decanters.

11. The method of claim 9, wherein a first decanter of the one or more decanters receives and separates the intermediate liquid product stream to produce an aqueous layer stream that comprises 4 wt. % to 10 wt. % glycolaldehyde, 5 wt. % to 7 wt. % dichloromethane, 20 wt. % to 30 wt. % amide solvent, and 47 wt. % to 71 wt. % water.

12. The method of claim 11, wherein the method further comprises flowing the aqueous layer stream to a second decanter of the one or more decanters and separating the aqueous layer stream into an aqueous product stream comprising 50 to 90 wt. % water, 5 to 30 wt. % amide solvent, 0.1 to 0.5 wt. % catalyst and an organic product stream comprising 70 to 90 wt. % dichloromethane, 10 to 30 wt. % amide solvent, 1 to 4 wt. % glycolaldehyde, 4 to 6 wt. % water.

13. The method of claim 11, wherein the first decanter of the one or more decanters produces an organic layer stream that comprises 70 wt. % to 90 wt. % dichloromethane, 15 wt. % to 25 wt. % amide solvent, more than 99 wt. % of the catalyst that was present in the reactor, and 4 wt. % to 6 wt. % water.

14. The method of claim 13, further comprising:

flowing the organic layer stream to a second flash vessel comprised in the separation unit and flashing the organic layer stream to produce (1) a gas stream comprising dichloromethane and water and (2) the organic product stream comprising the amide solvent and at least some of the catalyst.

15. The method of claim 12, further comprising: recycling the organic product stream to the reactor.

16. The method of any of claims 1 to 2, wherein the amide solvent comprises dimethyl acetami de .

17. The method of any of claims 1 to 2, wherein the catalyst comprises ( e.g RhClCO(PPh₃)₂, [Rh(COD)Cl]₂, Rh(CO)₂(acac), HRh(CO(PPh₃)₃, [Rh(CO)₂Cl]₂, and other complexes of rhodium).

18. The method of any of claims 1 to 2, wherein a weight ratio of amide solvent:dichloromethane:water in the intermediate liquid product stream is (5 to 20): (20 to 30): (5 to 15).