Abstract: Process for making purified hydrogen cyanide. The process includes feeding a reaction product including HCN, water, and organonitriles to a separation vessel; taking a liquid slip stream of HCN, water and organonitriles from the separation vessel; and feeding the liquid slipstream into a sidestream stripper to purge nitriles from the HCN reaction product.

Abstract: Process for making purified hydrogen cyanide. The process includes feeding a reaction product including HCN, water, and organonitriles to a separation vessel; taking a liquid slip stream of HCN, water and organonitriles from the separation vessel; and feeding the liquid slipstream into a sidestream stripper to purge nitriles from the HCN reaction product.

Abstract: A formaldehyde-containing product is separated from a formalin solution containing formaldehyde, water, and methanol by distilling in the presence of a water entraining compound, especially methyl propionate or methyl methacrylate. The product contains substantially less water than in the solution and may be used, for example, in a further process which requires a source of formaldehyde containing a relatively low level of water, for example, the catalyzed reaction of methy propionate with formaldehyde and methanol to produce methyl methacrylate.

Abstract: A process for the manufacture of methyl methacrylate includes a process for separating the methyl methacrylate from certain impurities, at least one of which has a freezing point of greater than −50° C., by a fractional crystallisation process.

Abstract: A formaldehyde-containing product is separated from a formalin solution containing formaldehyde, water and methanol by distilling the solution in the presence of a water entraining compound, especially methyl propionate or methyl methacrylate. The product contains substantially less water than in the solution and may be used, for example, in a further process which requires a source of formaldehyde containing a relatively low level of water, for example, the catalyzed reaction of methyl propionate with formaldehyde and methanol to produce methyl methacrylate.

Abstract: A process for separating a formaldehyde-containing product from a formalin solution comprising formaldehyde, water and methanol, wherein said formaldehyde-containing product contains substantially less water than said formalin solution, comprising distilling said formalin solution in the presence of a water entraining compound, especially methyl propionate or methyl methacrylate. The formaldehyde-containing product is suitable for use in a further process which requires a source of formaldehyde containing a relatively low level of water. One example of such a process is the reaction of methyl propionate with formaldehyde and methanol over a catalyst to produce methyl methacrylate.

Abstract: A process for the removal of formaldehyde species from a liquid carboxylic acid or carboxylic acid ester stream which forms a two-phase mixture with water is disclosed which comprises the step of subjecting the liquid organic mixture to at least one liquid liquid extraction stage wherein water is used as an extractant to produce an organic phase stream which is substantially formaldehyde free and an aqueous phase stream which contains substantially all of the formaldehyde in the output streams from the liquid liquid extraction. The process is particularly useful for reducing the formaldehyde content of a methyl methacrylate product stream.

Abstract: Fluid—fluid contacting apparatus is provided with a structured packing comprising a series of packing elements fabricated from sheets of crimped material in such a way that the corrugations in each sheet extend obliquely with respect to the direction of bulk fluid flow through the apparatus. Each packing element is oriented with the sheets thereof in a plane which is angularly displaced with respect to the sheets of neighboring elements. A mechanism is provided at or in the vicinity of the interface between neighboring elements for reducing the pressure drop imposed on the continuous phase as it passes from one element to the next.

Abstract: A method for recovering methyl acetate and residual acetic acid in a two-stage process for producing pure terephthalic acid having a first oxidation stage and a second purification stage.

Abstract: Process for producing pure terephthalic acid having improved means for recovering and/or recycling terephthalic acid precursors, residual acetic acid and other reaction by-products, such as methyl acetate.

Abstract: An improved process for preparing an aromatic dicarboxylic acid wherein the improvement resides in dehydrating and recovering solvent from a feed stream having from 20% to 40% by weight water via azeotropic distillation with organic phase reflux using an entrainer selected from isobutyl acetate, n-propyl acetate or an entrainer with a boiling point between isobutyl acetate and n-propyl acetate.