Abstract: Various embodiments of the present invention generally disclose systems and processes for the conversion of a feed stream comprising at least one C8 aromatic into a product stream comprising isophthalic acid and purified terephthalic acid (IPA/TA).

Abstract: High temperatures and oxygen exposure during extractive distillation can result in polymerization of vinyl aromatic compounds. In various embodiments, the present disclosure relates to methods for inhibiting polymerization of vinyl aromatic compounds during extractive distillation. In various embodiments, the methods include a) providing a mixture containing at least one vinyl aromatic compound, b) adding at least one dinitrophenol inhibitor to the mixture, and c) after step b), performing an extractive distillation on the mixture to isolate the at least one vinyl aromatic compound. Purified styrene can be isolated by the methods described herein. In some embodiments, the dinitrophenol inhibitor is 2-sec-butyl-4,6-dinitrophenol (DNBP).

Abstract: Various embodiments of the invention herein described generally relate to novel processes for the production of aromatic acids by fixed bed catalytic oxidation of aromatic compounds carrying at least one oxidizable substituent group attached directly to the carbon atom of the corresponding aromatic nucleus. In an embodiment, a novel oxidation process of the present invention comprises the steps of: a) catalytically oxidizing, with an oxidation catalyst, a liquid phase aromatic acid precursor in the presence of a gaseous oxygen source; b) separating a finished product; c) purging the solvent and the oxidation catalyst; d) optionally recycling at least a portion of the solvent into the oxidation reactor; e) recovering at least a portion of the oxidation catalyst; f) recharging the at least a portion of the oxidation catalyst over a solid recharging catalyst bed; and (g) feeding a reactivated oxidation catalyst to the oxidation reactor.

Abstract: Various embodiments of the invention herein described generally relate to novel processes for the production of aromatic acids by fixed bed catalytic oxidation of aromatic compounds carrying at least one oxidizable substituent group attached directly to the carbon atom of the corresponding aromatic nucleus. In an embodiment, a novel oxidation process of the present invention comprises the steps of: a) catalytically oxidizing, with an oxidation catalyst, a liquid phase aromatic acid precursor in the presence of a gaseous oxygen source; b) separating a finished product; c) purging the solvent and the oxidation catalyst; d) optionally recycling at least a portion of the solvent into the oxidation reactor; e) recovering at least a portion of the oxidation catalyst; f) recharging the at least a portion of the oxidation catalyst over a solid recharging catalyst bed; and (g) feeding a reactivated oxidation catalyst to the oxidation reactor.

Abstract: Various embodiments of the present invention generally disclose systems and processes for the conversion of a feed stream comprising at least one C8 aromatic into a product stream comprising isophthalic acid and purified terephthalic acid (IPA/TA).

Abstract: High temperatures and oxygen exposure during extractive distillation can result in polymerization of vinyl aromatic compounds. In various embodiments, the present disclosure relates to methods for inhibiting polymerization of vinyl aromatic compounds during extractive distillation. In various embodiments, the methods include a) providing a mixture containing at least one vinyl aromatic compound, b) adding at least one dinitrophenol inhibitor to the mixture, and c) after step b), performing an extractive distillation on the mixture to isolate the at least one vinyl aromatic compound. Purified styrene can be isolated by the methods described herein. In some embodiments, the dinitrophenol inhibitor is 2-sec-butyl-4,6-dinitrophenol (DNBP).

Abstract: An electrical circuit breaker comprises a base with two terminals embedded in, and extending through, the base. The external plug-in portions of the terminals are centered on the base. The internal portions of the terminals are off to one side in order to accommodate a PMB bimetal mounted on said internal portions. A cover secured to the base encloses the PMB bimetal.

Abstract: A thermistor assembly comprises a disc type thermistor bonded to a layer of a low expansion alloy which, in turn, is bonded to a thermally conductive plate. Interposition of the low expansion alloy between the thermistor and the plate substantially prevents the formation of hairline cracks in the thermistor that could result from thermal cycling.

Abstract: An electric choke assembly includes a heater to heat a coiled bimetallic spring which opens a choke valve. The heater comprises a double ring electroded thermistor for the purpose of generating two different heating rates which are controlled by a bimetallic thermostat blade located in the same chamber of the assembly as the thermistor.