Abstract: Accumulation of polymer on equipment, which is in contact with polymerizable material during normal process operation, is minimized by the method and apparatus of the present invention. The method involves positioning and affixing the equipment, such as a pressure relief device, to process apparatus, such as a distillation column, proximate to a wetted region formed by liquid phase fluid in the process apparatus, such that the moving liquid phase fluid is at least intermittently in contact with the equipment and one or more of accumulated polymerizable material, condensate including same, and polymer, is washed off of the equipment. The apparatus of the present invention is effective for maintaining the service-readiness of the equipment, which provides for safe long-term operation of the process apparatus.

Abstract: Accumulation of polymer on equipment, which is in contact with polymerizable material during normal process operation, is minimized by the method and apparatus of the present invention. The method comprises positioning and affixing the equipment, such as a pressure relief device, to process apparatus, such as a distillation column, proximate to a wetted region comprising liquid phase fluid in the process apparatus, such that the moving liquid phase fluid is at least intermittently in contact with the equipment and one or more of accumulated polymerizable material, condensate comprising same, and polymer, is washed off of the equipment. The apparatus of the present invention is effective for maintaining the service-readiness of the equipment, which provides for safe long-term operation of the process apparatus.

Abstract: Accumulation of polymer on equipment, which is in contact with polymerizable material during normal process operation, is minimized by the method and apparatus of the present invention. The method involves positioning and affixing the equipment, such as a pressure relief device, to process apparatus, such as a distillation column, proximate to a wetted region comprising liquid phase fluid in the process apparatus, such that the moving liquid phase fluid is at least intermittently in contact with the equipment and one or more of accumulated polymerizable material, condensate comprising same, and polymer, is washed off of the equipment.

Abstract: The present invention relates to recovery of aqueous (meth)acrylic acid by condensation of a (meth)acrylic acid-containing stream to produce aqueous (meth)acylic acid having a higher concentration of (meth)acrylic acid and a lower concentration of formaldehyde, i.e., not more than 0.1 weight %, than the aqueous (meth)acrylic acid produced using hithertofore known separation methods. The (meth)acrylic acid-containing stream may be the raw product stream of catalytic oxidation at least one C2-C4 alkane or alkene.

Abstract: The present invention relates to reducing corrosion of distillation equipment during azeotropic distillation of (meth)acrylic acid in the presence of dissolved copper, by providing aqueous (meth)acrylic acid having not more than 0.1% by weight formaldehyde, based on the total weight of the aqueous (meth)acrylic acid. The source of the copper may, for example, be copper-based polymerization inhibitors added to the aqueous (meth)acrylic acid and/or distillation equipment.

Abstract: The present invention relates to a method for blending and loading solid material into vessels, such as into the tubes of shell and tube reactors, in a manner which maximizes compositional homogeneity and consistency of quantities and configurations of the blended solid materials. The solid materials comprise one or more solid catalyst materials, one or more solid inert materials, or blends thereof.

Abstract: A method is provided herein for purifying (meth)acrylic acid to provide a purified (meth)acrylic acid product having a low aldehyde concentration and not more than 0.2 wt % water. One embodiment of the method includes distilling (meth)acrylic acid in the presence of an aldehyde treating compound. Another embodiment of the method includes also distilling crude (meth)acrylic acid in the presence of a reactive drying agent. (Meth)acrylic acid produced in this manner is especially suitable for use in specialty (meth)acrylic acid polymers, such as for example superabsorbent polymers, binders, and ethylene-(M)AA copolymers.

Abstract: The present invention provides a method for minimizing the decomposition of cyanohydrins in exothermic chemical reactions involving cyanohydrins. The method comprises providing a reaction medium and reactants to a tubular reactor having internal mixing means, mixing the reaction medium and reactants to form a homogenous reaction mixture, removing heat from the reaction process and reacting the reactants to produce a mixed product having a bulk temperature. The method may further comprise cooling the reaction medium to a temperature from 1-10° C. cooler than the bulk temperature of the mixed product prior to providing the reaction medium to the tubular reactor.

Abstract: A process is provided herein for the high yield production of high purity glacial methacrylic acid (“HPMAA”) that is substantially pure, specifically 99% pure or greater, with water content of 0.05% or less and low levels of other impurities, including HIBA, acrylic acid, MOMPA, methacrolein and others. This improved process comprises providing a crude MAA stream and purifying the crude methacrylic acid stream in a series of successive distillation steps involving two distillation columns. The inventive process is capable producing high purity methacrylic acid product that is especially suitable for the production of specialty MAA polymers.

Abstract: The present invention relates to reducing corrosion of distillation equipment during azeotropic distillation of (meth)acrylic acid in the presence of dissolved copper, by providing aqueous (meth)acrylic acid having not more than 0.1% by weight formaldehyde, based on the total weight of the aqueous (meth)acrylic acid. The source of the copper may, for example, be copper-based polymerization inhibitors added to the aqueous (meth)acrylic acid and/or distillation equipment.

Abstract: The present invention relates to recovery of aqueous (meth)acrylic acid by condensation of a (meth)acrylic acid-containing stream to produce aqueous (meth)acylic acid having a higher concentration of (meth)acrylic acid and a lower concentration of formaldehyde, i.e., not more than 0.1 weight %, than the aqueous (meth)acrylic acid produced using hithertofore known separation methods. The (meth)acrylic acid-containing stream may be the raw product stream of catalytic oxidation at least one C2-C4 alkane or alkene.

Abstract: The present invention provides a method for minimizing the decomposition of cyanohydrins in exothermic chemical reactions involving cyanohydrins. The method comprises providing a reaction medium and reactants to a tubular reactor having internal mixing means, mixing the reaction medium and reactants to form a homogenous reaction mixture, removing heat from the reaction process and reacting the reactants to produce a mixed product having a bulk temperature. The method may further comprise cooling the reaction medium to a temperature from 1-10° C. cooler than the bulk temperature of the mixed product prior to providing the reaction medium to the tubular reactor.

Abstract: In one embodiment, the invention provides a rupture disk assembly having a rupture disk and a rupture disk holder. The rupture disk holder has a first annular member downstream of the rupture disk, a second annular member upstream of the rupture disk, and an optional third annular member upstream of the second annular member. An outer peripheral portion of the rupture disk is sandwiched between the first and second annular members; and, if a third annular member is present, (a) the second annular member is sandwiched between the outer peripheral portion of the rupture disk and the third annular member, and (b) the third annular member includes a fluid port aimed at the rupture disk. However, if the third annular member is not present, the second annular member includes a fluid port aimed at the rupture disk.

Abstract: An improved process for ammonia recovery is provided for the recovery of substantially pure ammonia for use in industrial processes. In this improved method, specific raw materials and/or specific materials of construction are used. Overall efficiency and operational cost savings are increased as a result of the process of the present invention.

Abstract: The present invention provides an apparatus and method for efficiently dislodging and extracting at least a portion of solid materials from one or more reactor tubes of shell-and-tube reactors without damage to at least a portion of the solid materials which would otherwise render the solid materials unsuitable for re-use. The apparatus has at least one rod, a rotator assembly for rotating the rod, and a transmission assembly for applying an axially-directed force to insert the rod into a corresponding reactor tube and dislodging solid materials therein. The rod is also in fluid communication with an aspirator for extraction of dislodged solid materials. When the apparatus has more than one rod, they are arranged in a configuration matching the pattern of the reactor tubes and each rod is in axial alignment with a corresponding reactor tube.

Abstract: A process is provided herein for the high yield production of high purity glacial methacrylic acid (“HPMAA”) that is substantially pure, specifically 99% pure or greater with a water content of 0.05% or less.

Abstract: The present invention provides a method for minimizing the decomposition of cyanohydrins in exothermic chemical reactions involving cyanohydrins. The method comprises providing a reaction medium and reactants to a tubular reactor having internal mixing means, mixing the reaction medium and reactants to form a homogenous reaction mixture, removing heat from the reaction process and reacting the reactants to produce a mixed product having a bulk temperature. The method may further comprise cooling the reaction medium to a temperature from 1-10° C. cooler than the bulk temperature of the mixed product prior to providing the reaction medium to the tubular reactor.

Abstract: A method is provided herein for purifying (meth)acrylic acid to provide a purified (meth)acrylic acid product having a low aldehyde concentration and not more than 0.2 wt % water. One embodiment of the method includes distilling (meth)acrylic acid in the presence of an aldehyde treating compound. Another embodiment of the method includes also distilling crude (meth)acrylic acid in the presence of a reactive drying agent. (Meth)acrylic acid produced in this manner is especially suitable for use in specialty (meth)acrylic acid polymers, such as for example superabsorbent polymers, binders, and ethylene-(M)AA copolymers.

Abstract: A sulfur-bearing residue treatment system is provided for the recovery of valuable organic components and the reduction of capital costs and operating costs. The treatment system involves the use of a stripping vessel in conjunction with a heating apparatus. All elements of the treatment system may be coupled together to form one integral piece of equipment.

Abstract: The non-routine (e.g., emergency) shutdown of a chemical reaction process is achieved by a method of safely operating a chemical reaction process which comprises the steps of detecting an undesirable condition capable of affecting the process, minimizing the reaction of the reactants, and maintaining a flow of materials through the reaction zones of the process such that the reaction mixture is displaced from the reaction zones. The flow of materials may be maintained for a period of time such that the substantially all of the reaction mixture is displaced from the reaction zones, thereby flushing the reaction zones. The reaction mixture may then be purged to an ancillary vessel, such as an absorber.