A multi-reaction train hydroformylation process wherein a common product-catalyst separation zone is employed.

The present disclosure provides regioselective methods for synthesizing intermediates useful in making prostacyclin derivatives, such as treprostinil.

The present disclosure provides regioselective methods for synthesizing intermediates useful in making prostacyclin derivatives, such as treprostinil.

The invention relates to processes for preparing aldehydes by hydroformylation of alkenes, in which an alkene-containing feed mixture is subjected to a primary hydroformylation with synthesis gas in the presence of a homogeneous catalyst system, the primary hydroformylation being effected in a primary reaction zone from which a cycle gas containing at least some of the products and unconverted reactants of the primary hydroformylation are drawn off continuously and partly condensed, with recycling of uncondensed components of the cycle gas into the primary reaction zone, and with distillative separation of condensed components of the cycle gas in an aldehyde removal stage to give an aldehyde-rich mixture and a low-aldehyde mixture. The problem that it addresses is that of developing the process such that it achieves high conversions and affords aldehyde in good product quality even in the case of a deteriorating raw material position. More particularly, a solution is to be found for making legacy oxo process plants capable of utilizing lower-value raw material sources. This problem is solved by separating the low-aldehyde mixture into a retentate and a permeate by means of a membrane separation unit in such a way that alkenes present in the low-aldehyde mixture become enriched in the permeate, while alkanes present in the low-aldehyde mixture become enriched in the retentate. The alkene-rich permeate is then transferred into a secondary reaction zone and subjected to a secondary hydroformylation therein with synthesis gas in the presence of an SILP catalyst system. The reaction product obtained from the secondary hydroformylation is recycled into the aldehyde removal stage.

The present invention concerns regulating the water content in a process for production of methacrolein. Methacrolein is used in chemical synthesis particularly as an intermediate for production of methacrylic acid, methyl methacrylate or else of active, aroma or flavor chemicals. The present invention is particularly concerned with regulating the water content in a process for production of methacrolein from formaldehyde and propionaldehyde via a Mannich condensation.

A process for preparing acrylic acid from methanol and acetic acid, comprising (i) contacting a gaseous stream S0 comprising methanol, oxygen and inert gas with an oxidation catalyst to obtain a gaseous stream S1 comprising formaldehyde and inert gas; (ii) removing at least a portion of the inert gas present in S1 from at least a portion of the formaldehyde present in S1 by absorbing this formaldehyde in an absorbent to obtain a gaseous stream S2 comprising the portion of the inert gas removed, and to obtain a stream S3 comprising absorbent and absorbate comprising formaldehyde; (iii) optionally removing a portion or the entirety of the absorbent present in stream S3, such that a stream S3a remains from stream S3, and producing a stream S4 from at least stream S3 or stream S3a and a stream S5 comprising acetic acid; and (iv) contacting stream S4 in gaseous form with an aldol condensation catalyst to obtain a gaseous stream S6 comprising acrylic acid.

The present disclosure provides regioselective methods for synthesizing intermediates useful in making prostacyclin derivatives, such as treprostinil.

A method for extracting active principles from fruiting bodies of Antrodia camphorata comprises the steps of: extracting fruiting bodies of Antrodia camphorata with hot water to obtain extracts HW, and thus extraction residues (residues HW) are remained; extracting the residues HW by a fractional distillation to obtain extracts FD, and thus extraction residues (residues FD) are remained; extracting the residues FD by immersing with a low polar solvent to obtain extracts LPS, and thus extraction residues (residues LPS) are remained; extracting the residues LPS through a cryo-condensation process to obtain extracts IEW, and thus extraction residues (residues IEW) are remained; extracting the residues IEW through a SCF by using CO.sub.2 as a solvent to obtain extracts SCF, and thus extraction residues (residues SCF) are remained; and forming a mixture by mixing one or more extracts selected from the group consisting of extracts HW, FD, LPS, IEW, and SCF.

Provided is a method for producing fluorenone comprising an oxidation step of oxidizing fluorene in the presence of an aliphatic carboxylic acid having 2 to 3 carbon atoms, a metal catalyst, a bromine compound, and oxygen, and a phosphoric acid treatment step of bringing an oxidation reaction mixture into contact with phosphoric acid in the order indicated.

The process disclosure relates to processes for recovering rhodium from a hydroformylation process. In one aspect, a tails stream from a product-catalyst separation zone is provided to at least one organic solvent nanofiltration separation membrane, wherein a final permeate stream exits a final organic solvent nanofiltration separation membrane, wherein the rhodium concentration in the final permeate stream is lower than the rhodium concentration in the tails stream. The permeate stream is incinerated on-site to create a rhodium-containing ash.