Abstract: At least one pH-sensitive component may contact a refinery stream for measuring the pH of the refinery stream. A light from a light source may be emitted onto the pH-sensitive component, and a detector may detect a first luminescence or color change of chromophore measurement radiated from the pH-sensitive component. A first pH of the refinery stream may be determined from the first luminescence or color change of chromophore measurement.

Abstract: The polymerization of monomers may be at least partially reduced or inhibited by introducing an effective amount of an additive. The additive may be or include at least one hydroquinone, such as but not limited to, 2,6-di-tert-butyl hydroquinone, 2,5 di-tert-butyl hydroquinone, 3,5 di-tert-butyl hydroquinone, 3,5 di-methyl hydroquinone, 3,6 di-tert-butyl hydroquinone, and combinations thereof. The polymerizable monomers may be or include, but are not limited to styrene, butadiene, isoprene, acrylic acid, acrylonitrile, vinyl acetate, and combinations thereof.

Abstract: The polymerization of monomers may be at least partially reduced or inhibited by introducing an effective amount of an additive. The additive may be or include a first compound: where: R1 and R2 may be or include an alkyl group, an aryl group, an alkyl group having a heteroatom, an aryl group having a heteroatom, and combinations thereof. The hetero atom may be or include sulfur, nitrogen and/or oxygen. R1 may be the same or different from R2. The polymerizable monomers may be or include, but are not limited to styrene, butadiene, isoprene, acrylic acid, acrylonitrile, vinyl acetate, and combinations thereof.

Abstract: Sodium borohydride (NaBH4) may be used to removing carbonyl sulfide (COS) from a process stream containing it. The method involves contacting the process stream with an amount of effective of NaBH4 to react with the COS to form reaction products that may be removed by a process of washing away the reaction product by an aqueous basic compound and/or the reaction product having a higher boiling point than carbonyl sulfide which permits trapping the reaction product, such as in a caustic tower.

Abstract: The polymerization of monomers may be at least partially reduced or inhibited by introducing an effective amount of an additive. The additive may be or include a first compound: where: R1 and R2 may be or include an alkyl group, an aryl group, an alkyl group having a heteroatom, an aryl group having a heteroatom, and combinations thereof. The hetero atom may be or include sulfur, nitrogen and/or oxygen. R1 may be the same or different from R2. The polymerizable monomers may be or include, but are not limited to styrene, butadiene, isoprene, acrylic acid, acrylonitrile, vinyl acetate, and combinations thereof.

Abstract: In one embodiment, the present invention provides a method, comprising: a. adding an effective amount of at least one compound selected from the group consisting of a substituted catechol, nitroxide free radicals, a compound of Formula 2, 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl, phenol, hydroxylamine, and phenylene diamine to a solution of a monomer selected from the group consisting of acrylonitrile, acrylic acid, vinylacetate, acrylates and acrolein; b. placing the monomer solution containing the at least one compound in a pressure vessel, pressurizing the pressure vessel and removing oxygen from the pressure vessel; and c. heating the monomer solution containing the at least one compound, wherein the at least one compound inhibits fouling by preventing polymerization of the monomer.

Abstract: The polymerization of monomers may be at least partially reduced or inhibited by introducing an effective amount of an additive. The additive may be or include a first compound: where: R1 and R2 may be or include an alkyl group, an aryl group, an alkyl group having a heteroatom, an aryl group having a heteroatom, and combinations thereof. The hetero atom may be or include sulfur, nitrogen and/or oxygen. R1 may be the same or different from R2. The polymerizable monomers may be or include, but are not limited to styrene, butadiene, isoprene, acrylic acid, acrylonitrile, vinyl acetate, and combinations thereof.

Abstract: Sodium borohydride (NaBH4) may be used to removing carbonyl sulfide (COS) from a process stream containing it. The method involves contacting the process stream with an amount of effective of NaBH4 to react with the COS to form reaction products that may be removed by a process of washing away the reaction product by an aqueous basic compound and/or the reaction product having a higher boiling point than carbonyl sulfide which permits trapping the reaction product, such as in a caustic tower.

Abstract: At least one pH-sensitive component may contact a refinery stream for measuring the pH of the refinery stream. A light from a light source may be emitted onto the pH-sensitive component, and a detector may detect a first luminescence or color change of chromophore measurement radiated from the pH-sensitive component. A first pH of the refinery stream may be determined from the first luminescence or color change of chromophore measurement.

Abstract: A concentration of at least one oxygen species may be maintained within a pre-determined range in a water-based stream by obtaining at least one measurement as a direct current (DC) output with at least one probe within the water-based stream. The measurement(s) may correlate to a measured concentration of the oxygen specie(s) within the water-based stream. The measured concentration of the oxygen specie(s) within the water-based stream may be altered when the measured concentration is outside the pre-determined range.

Abstract: Methods and fluid compositions are described for decreasing or inhibiting foulants within an ethylene plant at a particular location, such as a caustic tower in a non-limiting embodiment. An effective amount of at least one substituted hydroxylamine and an effective amount of at least one aldol inhibitor may be introduced into a fluid feed of the ethylene plant. The aldol inhibitor(s) may be or include a substituted hydroxylimine, a borohydride, and combinations thereof.

Abstract: At least one probe may be introduced into a hydrocarbon stream for detecting dissolved oxygen species therein. The hydrocarbon stream may have or include at least one probing additive where the probing additive(s) may be added to the hydrocarbon stream, coated onto the probe(s), or both. The probe(s) may detect at least one luminescent measurement from the hydrocarbon stream, and the luminescent measurement(s) may determine whether dissolved oxygen species are present within the hydrocarbon stream.

Abstract: The polymerization of monomers may be at least partially reduced or inhibited by introducing an effective amount of an additive. The additive may be or include at least one hydroquinone, such as but not limited to, 2,6-di-tert-butyl hydroquinone, 2,5 di-tert-butyl hydroquinone, 3,5 di-tert-butyl hydroquinone, 3,5 di-methyl hydroquinone, 3,6 di-tert-butyl hydroquinone, and combinations thereof. The polymerizable monomers may be or include, but are not limited to styrene, butadiene, isoprene, acrylic acid, acrylonitrile, vinyl acetate, and combinations thereof.

Abstract: The polymerization of monomers may be at least partially reduced or inhibited by introducing an effective amount of an additive. The additive may be or include a first compound: where: R1 and R2 may be or include an alkyl group, an aryl group, an alkyl group having a heteroatom, an aryl group having a heteroatom, and combinations thereof. The hetero atom may be or include sulfur, nitrogen and/or oxygen. R1 may be the same or different from R2. The polymerizable monomers may be or include, but are not limited to styrene, butadiene, isoprene, acrylic acid, acrylonitrile, vinyl acetate, and combinations thereof.