Abstract: The present invention relates to a process for energy recovery in a process for the preparation of 1,3,5-trioxane.

Abstract: A process for producing a cyclic acetal is disclosed. According to the process, a formaldehyde source is combined with an aprotic compound and contacted with a heterogeneous catalyst which causes the formaldehyde source to convert into a cyclic acetal such as trioxane. The catalyst, for instance, may comprise a solid catalyst such as an ion exchange resin. In one embodiment, the process is used for converting anhydrous formaldehyde gas to trioxane. The anhydrous formaldehyde gas may be produced form an aqueous formaldehyde solution by an extractive distillation. The aprotic compound and the formaldehyde solution may be extracted from the reaction product and recycled into the process.

Abstract: This invention provides a method for preparing ethylene glycol by hydrolyzing ethylene glycol monomethyl ether.

Abstract: The present invention relates to a process for producing cyclic acetal comprising i) preparing a liquid reaction mixture comprising a) a formaldehyde source, b) an aprotic compound and c) a catalyst; wherein the total amount of protic compounds is less than 40 wt.-%, based on the total weight of the reaction mixture; and ii) converting the formaldehyde source into cyclic acetals.

Abstract: A process for producing a cyclic acetal is disclosed. According to the process, a formaldehyde source is combined with an aprotic compound and contacted with a heterogeneous catalyst which causes the formaldehyde source to convert into a cyclic acetal such as trioxane. The catalyst, for instance, may comprise a solid catalyst such as an ion exchange resin. In one embodiment, the process is used for converting anhydrous formaldehyde gas to trioxane. The anhydrous formaldehyde gas may be produced form an aqueous formaldehyde solution by an extractive distillation.

Abstract: A solid phosphoric acid catalyst which, when gas-phase synthesizing trioxane from formaldehyde, results in production of trioxane at a high yield and at a high selection rate by markedly suppressing side reactions, reduces the adhesion of organic matter to the catalyst surface, and achieves a stable and long-term catalyst reaction. This solid phosphoric acid catalyst contains silicon phosphate oxide (SPO) obtained by sintering at a temperature of at least 200° C. a carrier material to which a phosphoric acid component has been added, and the total quantity of acid does not exceed 5 mmol per 1 g of solid phosphoric acid catalyst when calculated as acid quantity determined by NH3-TPD measurement.

Abstract: A process for recycling polyoxymethylene polymers is disclosed. A polyoxymethylene polymer is at least partially dissolved in an aprotic compound. The resulting solution or suspension (liquid mixture) is then contacted with a catalyst which causes the polyoxymethylene polymer to be converted into a cyclic acetal. The cyclic acetal can be separated, collected and used in other processes. In one embodiment, the cyclic acetal may be used to produce a polyoxymethylene polymer.

Abstract: A process comprising for preparing C1 to C4 alkyl(meth)acrylates, such as butyl acrylate, wherein vaporized reactor contents are fed directly to a column, the aqueous reflux ratio to the column is from 4 to 12, and the level of acrylic acid in the primarily organic phase separated from the overhead condensate of the column is less than 2000 ppm.

Abstract: The present invention relates to a method for preparing 1,3,5-trioxane using a distillation tower including a reactor, a distillation section, and an extraction section. Particularly, the present invention relates to a method for preparing 1,3,5-trioxane, in which the water phase separated from the stream discharged through the extraction unit of the reaction distillation tower is used in the process of extracting 1,3,5-trioxane.

Abstract: The present invention relates to a method for preparing 1,3,5-trioxane using a reaction distillation tower including a reactor and integrally formed distillation and extraction sections. Particularly, the present invention relates to a method for preparing 1,3,5-trioxane characterized in that the amount of formaldehyde discharged to the outside of the system is reduced, to thereby increase the yield of 1,3,5-trioxane by recirculating a portion of the water phase, which is discharged through the top of the reaction extraction tower, to the extraction section, and thus to the upper portion of the extractor supply stream which supplies extractant to the extraction section.

Abstract: A process for producing a cyclic acetal is disclosed. According to the process, a formaldehyde source is combined with an aprotic compound and contacted with a heterogeneous catalyst which causes the formaldehyde source to convert into a cyclic acetal such as trioxane. The catalyst, for instance, may comprise a solid catalyst such as an ion exchange resin. In one embodiment, the process is used for converting anhydrous formaldehyde gas to trioxane. The anhydrous formaldehyde gas may be produced form an aqueous formaldehyde solution by an extractive distillation.

Abstract: The present invention relates to a process for producing cyclic acetal comprising i) preparing a liquid reaction mixture comprising a) a formaldehyde source, b) an aprotic compound and c) a catalyst; wherein the total amount of protic compounds is less than 40 wt.-%, based on the total weight of the reaction mixture; and ii) converting the formaldehyde source into cyclic acetals.

Abstract: The present invention relates to a process for producing cyclic acetal comprising i) preparing a reaction mixture comprising a) a formaldehyde source in a liquid medium and b) a catalyst; ii) converting the formaldehyde source into cyclic acetals, wherein the final conversion of said formaldehyde source to said cyclic acetal is greater than 10% on basis of the initial formaldehyde source.

Abstract: A process for recycling polyoxymethylene polymers is disclosed. A polyoyxmethylene polymer is at least partially dissolved in an aprotic compound. The resulting solution or suspension (liquid mixture) is then contacted with a catalyst which causes the polyoxymethylene polymer to be converted into a cyclic acetal. The cyclic acetal can be separated, collected and used in other processes. In one embodiment, the cyclic acetal may be used to produce a polyoxymethylene polymer.

Abstract: A process for producing cyclic acetals is described. A formaldehyde source is contacted with an aprotic compound in the presence of a catalyst to produce the cyclic acetals. The aprotic compound can increase conversion rates and/or efficiency. In one embodiment, the formaldehyde source is obtained from methanol. In particular, methanol can be converted into formaldehyde which is then converted into a cyclic acetal. In one embodiment, the cyclic acetal can then be used to produce oxymethylene polymers.

Abstract: A process for recovering volatile components from an oxymethylene polymer process is disclosed. The volatile components are removed from the process and the formaldehyde collected is converted to a cyclic acetal. The formaldehyde is converted to a cyclic acetal by contacting the formaldehyde with a catalyst in the presence of an aprotic solvent.

Abstract: The present invention relates to a process for producing cyclic acetal comprising i) preparing a liquid reaction mixture comprising a) formaldehyde source, b) an aprotic compound and c) a catalyst; and ii) converting the formaldehyde source into cyclic acetals.

Abstract: The present invention relates to a method for preparing 1,3,5-trioxane using a reaction distillation tower including a reactor and integrally formed distillation and extraction sections. Particularly, the present invention relates to a method for preparing 1,3,5-trioxane characterized in that the amount of formaldehyde discharged to the outside of the system is reduced, to thereby increase the yield of 1,3,5-trioxane by recirculating a portion of the water phase, which is discharged through the top of the reaction extraction tower, to the extraction section, and thus to the upper portion of the extractor supply stream which supplies extractant to the extraction section.

Abstract: The present invention relates to a method for preparing 1,3,5-trioxane using a distillation tower including a reactor, a distillation section, and an extraction section. Particularly, the present invention relates to a method for preparing 1,3,5-trioxane, in which the water phase separated from the stream discharged through the extraction unit of the reaction distillation tower is used in the process of extracting 1,3,5-trioxane.

Abstract: Processes are disclosed comprising: (a) reacting an aqueous formaldehyde solution in a reactor in the presence of a suitable catalyst to obtain a reaction product mixture comprising trioxane, formaldehyde and water; (b) distilling the reaction product mixture to form a top stream comprising crude trioxane; and (c) treating the top stream in one or more additional stages to form pure trioxane; wherein an aqueous sidestream is drawn off during the distilling of the reaction mixture.

Abstract: An integrated process for preparing trioxane from formaldehyde.

Abstract: A process for removing trioxane from a use stream I of formaldehyde, trioxane and water, by a) providing a use stream I which comprises formaldehyde as the main component and trioxane and water as the secondary components, b) feeding the use stream I, a recycle stream V and a recycle stream VII which comprises formaldehyde as the main component and water and trioxane as the secondary components into a first distillation stage and distilling to obtain a stream II a steam III and formaldehyde as the and a steam X c) distilling the stream III, in a second distillation stage the pressure in the second distillation stage being from 0.

Abstract: A process for separating trioxane from a feed stream I comprising formaldehyde, trioxane and water, in which a) a feed stream I comprising formaldehyde as main component and trioxane and water as secondary components is provided, b) the feed stream I, a recycle stream V and a recycle stream VII comprising formaldehyde as main component and water and trioxane as secondary components are fed into a first distillation stage and distilled at a pressure of from 0.1 to 2.5 bar to give a stream II comprising formaldehyde as main component and water as secondary component and a stream III comprising trioxane as main component and water and formaldehyde as secondary components and a stream X comprising water, trioxane and formaldehyde, c) the stream III is, if appropriate after removal of low boilers from the stream III in a low boiler removal stage, distilled in a second distillation stage at a pressure of from 0.2 to 17.5 bar, with the pressure in the second distillation stage being from 0.

Abstract: Process for preparing polyoxymethylenes by polymerization of the monomers a) in the presence of cationically active initiators b) and, if appropriate in the presence of regulators c) and subsequent deactivation d) and discharge from the reactor, wherein at least one ionic liquid is used as initiator b).

Abstract: A process for preparing crude trioxane (1) having a concentration in the range from 50 to 75% by weight of trioxane by trimerization of formaldehyde from an aqueous formaldehyde solution (2) in the presence of an acid catalyst (3) and concentration of the trioxane from the reaction mixture from the trimerization by distillation, wherein the trimerization of the formaldehyde and the concentration of the trioxane from the reaction mixture from the trimerization are carried out in a single column (K) which is divided by a horizontal dividing plate (T) into a lower column region (A) and an upper column region (B), with the lower column region (A) and the upper column region (B) being connected by an external vapor line and an external liquid line, and a reactive distillation in which the formaldehyde is trimerized to trioxane and the trioxane in the reaction mixture is concentrated to the solubility limit of formaldehyde is carried out in the lower column region (A) at a pressure in the range from 1 to 5 bar a

Abstract: The invention relates to an integrated process for preparing trioxane from formaldehyde in which a stream A1 comprising water and formaldehyde and a recycle stream B2 consisting substantially of water and formaldehyde are fed to a trioxane synthesis reactor in which the formaldehyde is converted to trioxane to obtain a product stream A2 comprising trioxane, water and formaldehyde; stream A2 is fed to a first distillation column and distilled at a pressure in the range from 0.1 to 2.5 bar to obtain a stream B1 enriched in trioxane, and the stream B2 consisting substantially of water and formaldehyde; stream B1 and a recycle stream D1 comprising trioxane, water and formaldehyde are fed to a second distillation column and distilled at a pressure in the range from 0.2 to 17.5 bar to obtain a product stream C2 consisting substantially of trioxane, and a stream C1 comprising trioxane, water and formaldehyde; stream C1 is fed to a third distillation column and distilled at a pressure in the range from 0.1 to 2.

Abstract: A process for preparing trioxane from trioxymethylene glycol dimethyl ether (POMDMEn=3) by converting trioxymethylene glycol dimethyl ether in the presence of an acidic catalyst and subsequent distillative workup of the reaction mixture, comprising the steps of: a) feeding trioxymethylene glycol dimethyl ether (POMDMEn=3) or a mixture comprising trioxymethylene glycol dimethyl ether into a reactor and converting it in the presence of an acidic catalyst to a mixture a comprising trioxane, formaldehyde, water, methylene glycol (MG), polyoxymethylene glycols (MGn>1), methanol, hemiformals (HF), methylal (POMDMEn=1) and polyoxymethylene glycol dimethyl ethers (POMDMEn>1); b) distillatively separating the reaction mixture a into a low boiler fraction b1 comprising formaldehyde, water, methylene glycol, methanol, hemiformal (HFn=1), methylal and dioxymethylene glycol dimethyl ether (POMDMEn=2), and a high boiler fraction b2 comprising trioxane, polyoxymethylene glycols (MGn>1), hemiformals (HFn>1) and

Abstract: A process for preparing trioxane from trioxymethylene glycol dimethyl ether (POMDMEn=3) by converting trioxymethylene glycol dimethyl ether in the presence of an acidic catalyst and subsequent distillative workup of the reaction mixture, comprising the steps of: a) feeding trioxymethylene glycol dimethyl ether (POMDMEn=3) or a mixture comprising trioxymethylene glycol dimethyl ether into a reactor and converting it in the presence of an acidic catalyst to a mixture a comprising trioxane, formaldehyde, water, methylene glycol (MG), polyoxymethylene glycols (MGn>1), methanol, hemiformals (HF), methylal (POMDMEn=1) and polyoxymethylene glycol dimethyl ethers (POMDMEn>1); b) distillatively separating the reaction mixture a into a low boiler fraction b1 comprising trioxane, formaldehyde, water, methylene glycol, methanol, hemiformal (HFn=1), methylal and dioxymethylene glycol dimethyl ether (POMDMEn=2), and a high boiler fraction b2 comprising polyoxymethylene glycols (MGn>1), hemiformals (HFn>1) and

Abstract: A process for removing trioxane from a use stream I of formaldehyde, trioxane and water, by a) providing a use stream I which comprises formaldehyde as the main component and trioxane and water as the secondary components, b) feeding the use stream I, a recycle stream V and a recycle stream VII which comprises formaldehyde as the main component and water and trioxane as the secondary components into a first distillation stage and distilling at a pressure of from 0.1 to 2.5 bar to obtain a stream II which comprises formaldehyde as the main component and water as the secondary component, and a stream III which comprises trioxane as the main component and water and formaldehyde as the secondary components, and a stream X which comprises water, trioxane and formaldehyde, c) distilling the stream III, optionally after removing low boilers from the stream III in a low boiler removal stage, in a second distillation stage at a pressure of from 0.2 to 17.

Abstract: A process for removing trioxane from a use stream I of formaldehyde, trioxane and water, by a) providing a use stream I of formaldehyde as the main component and trioxane and water as the secondary components, b) mixing the use stream I with a recycle stream VII to obtain a feed stream Ia, c) distilling the use stream Ia in a first distillation stage to obtain a stream II of formaldehyde as the main component and water as the secondary component, and a stream III of trioxane as the main component and water and formaldehyde as the secondary components, d) distilling the stream III in a second distillation stage having a pressure higher than in the first distillation stage, to obtain a stream IV of trioxane and a stream V of trioxane as the main component and water and formaldehyde as the secondary components, e) distilling the stream V in a third distillation stage to obtain a stream VI of water and the recycle stream VII of trioxane as the main component and water and formaldehyde as the secondary components

Abstract: The present invention relates to a process for synthesizing trioxymethylene, wherein an aqueous solution of formaldehyde is used as the reactant; and an acidic ionic liquid in an amount of from 0.01 to 10 wt % is used as a catalyst.

Abstract: An integrated process for preparing trioxane from formaldehyde, comprising the steps of: a) feeding a feed stream A1 comprising formaldehyde and water and a recycle stream B3 comprising predominantly water and additionally formaldehyde and trioxane to a formaldehyde concentration unit and separating it into a formaldehyde-rich stream A2 and a stream A3 consisting essentially of water; b) feeding a product stream C1 comprising trioxane, water and formaldehyde, a recycle stream E1 comprising trioxane, water and formaldehyde, and, if appropriate, the stream A2 to a first low-pressure distillation column and distilling at a pressure of from 0.1 to 1.

Abstract: The present invention relates to a process for synthesizing trioxymethylene, wherein an aqueous solution of formaldehyde is used as the reactant; and an acidic ionic liquid in an amount of from 0.01 to 10 wt % is used as a catalyst.

Abstract: The invention relates to an integrated process for preparing trioxane from formaldehyde in which, in a first step, a stream A1 comprising water and formaldehyde and a recycle stream B2 consisting substantially of water and formaldehyde are fed to a trioxane synthesis reactor in which the formaldehyde is converted to trioxane to obtain a product stream A2 comprising trioxane, water and formaldehyde. Stream A2 and a recycle stream D1 comprising trioxane, water and formaldehyde are fed to a first distillation column and distilled at a pressure in the range from 0.1 to 2.5 bar to obtain a stream B1 enriched in trioxane, and the stream B2 consisting substantially of water and formaldehyde. Stream B1 is fed to a second distillation column and distilled at a pressure in the range from 0.2 to 17.5 bar to obtain a product stream C2 consisting substantially of trioxane, and a stream C1 comprising trioxane, water and formaldehyde.

Abstract: The invention relates to an integrated process for preparing trioxane from formaldehyde, comprising the steps of: a) a stream A1 comprising water and formaldehyde and a recycle stream B2 consisting substantially of water and formaldehyde are fed to a trioxane synthesis reactor and allowed to react to obtain a product stream A2 comprising trioxane, water and formaldehyde; b) stream A2 is fed to a first low-pressure distillation column and distilled at a pressure of from 0.1 to 2.5 bar to obtain a stream B1 enriched in trioxane and additionally comprising water and formaldehyde, and the recycle stream B2 consisting substantially of formaldehyde and water; c) stream B1 and a recycle stream D1 comprising trioxane, water and formaldehyde are fed to a second low-pressure distillation column and distilled at a pressure of from 0.1 to 2.

Abstract: The present invention relates to a method of synthesizing trioxymethylene from formaldehyde by the catalytic action of an acidic ionic liquid. In the method, formaldehyde solution with a concentration of 30˜80 wt % is used as reactant, and an ionic liquid is used as catalyst. The cation moiety of the catalyst is selected from either imidazoles cation or pyridines cation, and the anion moiety of the catalyst is selected from one of p-tolyl benzene sulfonate, trifluoromethyl sulfonate, and hydrogen sulfate. In the present invention, ionic liquid is used, for the first time, as a catalyst to synthesize trioxymethylene from formaldehyde. The catalyst can be circularly used for continuous sampling.

Abstract: A process for the separation of an aqueous mixture of trioxane and formaldehyde and corresponding applications are disclosed. The aqueous trioxane and formaldehyde mixture has a first trioxane:formaldehyde ratio, and the process comprises a step of reacting the aqueous mixture of trioxane and formaldehyde with urea and a step of separating an exiting vapour phase having a second trioxane:formaldehyde ratio that is higher than the first trioxane:formaldehyde ratio. Possible applications of the process are for the separation of an aqueous mixture of trioxane and formaldehyde coming from a reactor in which trioxane is being synthesized or from a distillation column in which a prior aqueous mixture of trioxane and formaldehyde is separated from the excess formaldehyde. Another possible application is for preparing raw material for the production of urea-formaldehyde glues or resins.

Abstract: In the present invention relates to a novel series of antimalarial 1,2,4-trioxanes analogues of general formula 7, wherein R represents cycloalkyl groups selected from the groups consisting of cyclopentyl, cyclohexyl, cycloheptyl and cyclooctyl or aryl groups selected from phenyl, 4-bromophenyl and 4-chlorophenyl, R1 and R2 represent hydrogen, alkyl group selected from methyl, ethyl, propyl and decyl, aryl selected from phenyl or parts of a cyclic systems such as cyclopentane, cyclohexane, substituted cyclohexane, cycloheptane bicyclo(2.2.1)heptane, adamantane and its preparation thereof; several of these novel compounds show promising antimalarial activity against multidrug resistant malaria in mice.

Abstract: An object of the present invention is to provide a novel compound having antimalarial acitivity and an antimalarial agent containing the novel compound as an active component. An antimalarial agent containing 12-hidroxy-2-(1-methoxy-carbonylethyl)-5-oxo-10,11,13-trioxatricyclo[7.2.0.01,6]tridecane represented by a following formula (II) as an active agent is prepared.

Abstract: A process for preparing trioxane by converting methanol to formaldehyde by dehydrogenation at a temperature of 300 to 1000° C., in the presence of a catalyst, wherein the catalyst is generated physically separately from the reactor and at a temperature above the dehydrogenation temperature, and trimerizing the formaldehyde prepared in this way to give trioxane. Also described is a process for preparing polyoxymethylene and polyoxymethylene copolymers from the formaldehyde.

Abstract: Disclosed are novel coumarin based fluorogenic compounds useful in assaying for biological activity. Specifically, these fluorogenic compounds exhibit fluorescence at particular wavelengths when cleaved by target enzymes. Preferred compounds include sugar and peptide derivatives of umbelliferone derivatives bearing a heterocyclic five membered ring at the 3-position. These compounds can be used for rapidly detecting food pathogens and for determining sterilization effectiveness. The compounds may also be used in a form bounded to a polymeric support or to a biomolecule or macromolecule.

Abstract: In a process for preparing formaldehyde from methanol by dehydrogenation in a reactor in the presence of a catalyst at a temperature in the range from 300 to 1000° C., a carrier gas stream which has a temperature above the dehydrogenation temperature is fed to the reactor.

Abstract: Powder coating compositions comprise a binder selected from carboxyl-group-containing polyesters, carboxyl-group-containing poly(meth)acrylates and mixtures of the said substances, and one or more epoxy compounds, wherein the epoxy compounds comprise at least one compound of formula (I) that is solid at 25° C.

Abstract: Process for the removal of trioxane from a liquid mixture comprising trioxane, formaldehyde, alcohol, hemiformals formed from the form-aldehyde and the alcohol, usual secondary components arising in the preparation of trioxane, and, in addition or as an alternative to the alcohol and the hemiformals, water, in which the trioxane is transferred into the gas phase by vaporization or evaporation and subsequently converted into a liquid state by condensation and obtained as condensate or converted into a solid state by desublimation and obtained as desublimate. Through the process, an increase in the concentration of the trioxane by 2.5 times or more is achieved.

Abstract: Processes for making trioxane, polyoxymethylene and polyoxymethylene copolymers from formaldehyde, made by the dehydrogenation of methanol in the presence of a catalytic active species set free from a sodium compound, at a temperature in the range of 300° C. to 1000° C., wherein a carrier gas stream which has a temperature above the dehydrogenation temperature is fed to the reactor.

Abstract: Disclosed are novel coumarin based fluorogenic compounds useful in assaying for biological activity. Specifically, these fluorogenic compounds exhibit fluorescence at particular wavelengths when cleaved by target enzymes. Preferred compounds include sugar and peptide derivatives of umbelliferone derivatives bearing a heterocyclic five membered ring at the 3-position. These compounds can be used for rapidly detecting food pathogens and for determining sterilization effectiveness. The compounds may also be used in a form bounded to a polymeric support or to a biomolecule or macromolecule.

Abstract: The present invention relates to novel substituted 1,2,4-trioxanes that are useful as anti-malarial agents, and have a general formula 1, wherein R1 and R2 are selected from the group consisting of a hydrogen, a C1-11 alkyl group; R3 and R4 are selected from the group consisting of a hydrogen, a C1-11 alkyl group, a C3-10 aryl group, a C1-2CO2H carboxyalkyl group; and X represents hydrogen or a lower alkoxy group having 1 to 6 carbons.

Abstract: A process for the gas-phase trimerization of formaldehyde to give trioxane using solid phosphoric acid catalysts. Particularly suitable catalysts for this process are SPA catalysts (solid phosphorous acid), for example “silicon phosphates”. The main advantage of this catalyst system is its simple and inexpensive production and ready availability and also, in particular, its improved long-term stability compared to the few previously described catalysts which are mostly based on supported heteropolyacids.

Abstract: Methods for producing novel artemisinin analogs and artemisinin dimers having antimalarial, antiproliferative and antitumor activities are described herein. These novel artemisinin analogs and artemisinin dimers have the following structure or diastereomers thereof, having antimalarial, and antiproliferative and antitumor activities wherein, the monomers of the present invention are formed when n is 1 and R is alkyl, cycloalkyl, heteroalkyl, heterocycloalkyl, alkenyl, alkynyl, aryl or heteroaryl. The dimers of the present invention are formed when n is 2 and R is a linker including, but not limited to, alkyl, cycloalkyl, heteroalkyl, heterocycloalkyl, alkenyl, alkynyl, aryl or heteroaryl.

Abstract: A process for isolating trioxane from an aqueous mixture which includes trioxane, water and formaldehyde, including removing trioxane from the mixture by pervaporation, and subjecting the mixture enriched in trioxane (permeate) to rectification to give trioxane and an azeotropic mixture of trioxane, water and formaldehyde.