Abstract: A system for the removal of heat stable amine salts from an amine absorbent used in a carbon dioxide (CO2) capture process.

Abstract: The present invention relates to making tetra-sulfo iron-phthalocyanine by reacting sulfonated reactant(s) in the presence a boron-containing promoter. The present invention also relates to making tetra-sulfo iron phthalocyanine more tolerant to oxygen by combining the tetra-sulfo iron-phthalocyanine with a stabilizing amount of a complexing agent (e.g., a stabilizing amine) and/or contacting the tetra-sulfo iron-phthalocyanine with steam.

Abstract: A composition for removing mercaptan from a gas stream containing at least one acid gas in addition to a mercaptan, the composition comprising a physical and/or chemical solvent for H2S and an inclusion compound for the mercaptan. A process of treating gas stream using the composition. The inclusion compound is selected from the group consisting of, cyclodextrin, cryptand, calixarene, cucurbituril. The chemical solvent may be monoethanolamine (MEA), diethanolamine (DEA), triethanolamine (TEA, diisopropylamine (DIPA), diglycolamine (DGA) and methyldiethanolamine (MDEA). Examples of useful physical solvents include cyclotetramethylene sulfone (sulfolane) and its derivatives, aliphatic acid amides, NMP (n-methylpyrrolidone), N-alkylated pyrrolidones and corresponding piperidone, methanol and mixtures of dialkethers of polyethylene glycols. The method comprises scrubbing preferably the natural gas with an aqueous solution comprising the above compounds followed by a stripping regeneration step.

Abstract: A composition for removing mercaptan from a gas stream containing at least one acid gas in addition to a mercaptan, the composition comprising a physical and/or chemical solvent for H2S and an inclusion compound for the mercaptan. A process of treating gas stream using the composition. The inclusion compound is selected from the group consisting of, cyclodextrin, cryptand, calixarene, cucurbituril. The chemical solvent may be monoethanolamine (MEA), diethanolamine (DEA), triethanolamine (TEA, diisopropylamine (DIPA), diglycolamine (DGA) and methyldiethanolamine (MDEA). Examples of useful physical solvents include cyclotetramethylene sulfone (sulfolane) and its derivatives, aliphatic acid amides, NMP (n-methylpyrrolidone), N-alkylated pyrrolidones and corresponding piperidone, methanol and mixtures of dialkethers of polyethylene glycols. The method copirses scrubbing preferably the natural gas with an aqueous solution comprising the above compounds followed by a stripping regeneration step.

Abstract: The present disclosure describes the efficient use of a catalyst, an enzyme for example, to provide suitable real cyclic capacity to a solvent otherwise limited by its ability to absorb and maintain a high concentration of CO2 captured from flue gas. This invention can apply to non-promoted as well as promoted solvents and to solvents with a broad range of enthalpy of reaction.

Abstract: A composition for removing mercaptan from a gas stream containing at least one acid gas in addition to a mercaptan, the composition comprising a physical and/or chemical solvent for H2S and an inclusion compound for the mercaptan. A process of treating gas stream using the composition. The inclusion compound is selected from the group consisting of, cyclodextrin, cryptand, calixarene. cucurbituril. The chemical solvent may be monoethanolamine (MEA), diethanolamine (DEA), triethanolamine (TEA, diisopropylamine (DIPA), diglycolamine (DGA) and methyldiethanolamine (MDEA). Examples of useful physical solvents include cyclotetramethylene sulfone (sulfolane) and its derivatives, aliphatic acid amides, NMP (n-methylpyrrolidone), N-alkylated pyrrolidones and corresponding piperidone methanol and mixtures of dialkethers of polyethylene glycols. The method copirses scrubbing preferably the natural gas with an aqueous solution comprising the above compounds followed by a stripping regeneration step.

Abstract: The present invention relates to making tetra-sulfo iron-phthalocyanine by reacting sulfonated reactant(s) in the presence a boron-containing promoter. The present invention also relates to making tetra-sulfo iron phthalocyanine more tolerant to oxygen by combining the tetra-sulfo iron-phthalocyanine with a stabilizing amount of a complexing agent (e.g., a stabilizing amine) and/or contacting the tetra-sulfo iron-phthalocyanine with steam.

Abstract: A process is disclosed for removing aromatics, and volatile organic hydrocarbons from a gaseous fluid stream including passing the fluid stream in contact with a dehydrating composition comprising a glycol selected from triethylene glycol, ethylene glycol, diethylene glycol, or mixtures thereof and a hydrocarbon solubility depressant. The dehydrating composition may also contain a dissolved salt including at least one alkali metal carboxylate, an ammonium carboxylate, an alkali metal halide, an ammonium halide, or a mixtures thereof.

Abstract: The simultaneous abatement of NO and SO.sub.2 in flue gas is provided by an absorption process and apparatus utilizing an absorbent composition comprising an aqueous solution of chelates and sulfite salt for NO abatement and amine SO.sub.2 absorbents such as piperazinones, morpholinones, piperidines, piperazines, piperazinediones, hydantoins, triazinones, pyrimidinones, oxazolidones, etc. for SO.sub.2 abatement. SO.sub.2 is thermally stripped from the spent absorbent and recovered. Metal chelates oxidized to an inactive state as a side-reaction are electrochemically reduced. An anionic exchange membrane in the electrochemical cell regenerates heat stable amine salt byproducts to be converted back to useable amine sorbent, and facilitates removal from the absorbent solution of other waste salts.

Abstract: H.sub.2 S is removed from a fluid stream by contacting the stream with an aqueous solution having at least two components: an effective amount of an iron (III) chelate to oxidize H.sub.2 S to sulfur and, an amount of a water soluble anionic polymer containing sulfonic acid groups, carboxyl groups or mixtures thereof which is effective to stabilize the chelate. During the removal process the iron chelate is reduced to iron(II) chelate, and sulfur particles are produced.

Abstract: The simultaneous abatement of NO and SO.sub.2 in flue gas is provided by an absorption process and apparatus utilizing an absorbent composition comprising an aqueous solution of chelates and sulfite salts. Metal chelates oxidized to an inactive state are electrochemically reduced. In the electrochemical cell, nickel or stainless steel anode materials are stable and may be used in the place of platinum coated anode materials when the anolyte pH is maintained greater than 12. At these conditions, the anode is corrosion resistant with a long operating time between replacement. Ultrafiltration or Donnan dialysis may be used to separate the chelate sorbents from the waste salts to reduce the loss of expensive chelate sorbents. Alternatively, an anionic exchange membrane can be used to electrodialytically separate waste sulfur/nitrogen salts from the absorbent solution.

Abstract: Inhibitors of oxidation of sulfites to sulfates in sulfur dioxide scrubbing solutions are disclosed. The inhibitors are cationic polyelectrolytes which are water soluble, have a molecular weight of at least 10,000 daltons and contain quaternary amine groups. The polyelectrolytes are preferably present at 1-3000 ppm in alkali solutions with which a sulfur dioxide containing gas stream is contacted. The scrubbing solutions contain amines such as piperazinones, morpholinones, piperidines, piperazines, piperazinediones, hydantoins, triazinones, pyrimidinones, oxazolidones, N-carboxymethyl ethylenediamines, etc.

Abstract: H.sub.2 S abatement in geothermal drilling operations (e.g. drilling, flow testing and reworking) with a ferric aminocarboxylic acid chelating solution containing a stabilizer and an optional cationic polyelectrolyte catalyst which is injected in the blooie line of the well upstream of the separator. The stabilizer is a hydroxyl radical scavenger such as iodide, nitrite, amino acid, aliphatic aldehyde, sugar, ascorbate, formate and/or aryl sulfonic acid, and inhibits degradation the ferric aminocarboxylic acid complex.

Abstract: In a process of cyclodimerizing a conjugated diene to form a cycloalkene using a soluble iron complex as catalyst, the improvement comprises using as an inhibitor of diene polymerization, at least one hindered phenol.

Abstract: Inhibitors of oxidation of sulfites to sulfates in sulfur dioxide scrubbing solutions are disclosed. The inhibitors are cationic polyelectrolytes which are water soluble, have a molecular weight of at least 10,000 daltons and contain quaternary amine groups. The polyelectrolytes are preferably present at 1-3000 ppm in alkali solutions with which a sulfur dioxide containing gas stream is contacted.

Abstract: A process for abating hydrogen sulfide during geothermal steam stacking operations is disclosed. The geothermal steam to be stacked is introduced into a geothermal steam stacking line. Ferric chelating solution is injected into the stacking line in an amount effective to convert the hydrogen sulfide in the steam to sulfur. The hydrogen sulfide-abated steam and chelating solution is vented through a rock muffler and the chelating solution is optionally recovered from the muffler, regenerated and recirculated to the injection step.

Abstract: Geothermal steam is condensed with a sulfite solution to abate hydrogen sulfide. A portion of the hydrogen sulfide is converted in the condensation in the presence of soluble cationic polymeric catalysts to soluble sulfur compounds while avoiding elemental sulfur and carbonate formation. The remainder of the hydrogen sulfide is incinerated and the sulfur dioxide in the incinerator effluent is absorbed in an alkaline solution to form the sulfites for the geothermal steam condensation. By maintaining stoichiometric ratios, the hydrogen sulfide is substantially converted to soluble thiosulfate without the use of chelates, peroxides or makeup sulfites.

Abstract: An NO abatement process wherein an NO-containing fluid is contacted with a polymeric cobalt(II) dioxygen diamine complex. The aqueous solution is recovered, purified by membrane separation to remove low molecular weight reaction products, optionally electrolytically regenerated, and recycled for the NO-containing gas contact. The cobalt(II) is complexed with an amine-containing polymer such as polyethyleneimine free of acidic, e.g. carboxylate, chelating groups.

Abstract: Soluble chemical compounds having a high affinity for hydroxyl radicals are effective stabilizers for chelating agents used in the hydrogen sulfide removal process. The stabilizers include aromatic compounds, bromide ions, iodide ions, cyanides, nitrites, amino acids, sugars, ascorbates, alcohols, polyols, aliphatic aldehydes, compounds having unsaturated carbon-carbon bonds, dimethyl sulfoxide, organic disulfides, alkyl amines, and formates. The aromatic compounds have the additional benefit of combining with hydroxyl radicals to form chelating agents.

Abstract: A structural low carbon steel in combination with and in contact with an aqueous MDEA solvent that includes as an amine-based chemical additive. When mixed with MDEA solvent to form a MDEA solution, the MDEA-based solution in contact with carbon steel reduces the corrosion rate of low carbon structural carbon steels having a carbon content greater than about 0.18% by weight is significantly reduced when the concentrations of CO2, O2 and heat stable salts (HSS) are controlled below critical amounts. The MDEA solution, when controlling the concentrations of CO2, O2 and HSS below critical amounts, suppresses the corrosion of carbon steel having a carbon content greater than about 0.18%. A smooth surface finish further suppresses the corrosion of the low carbon structural steel. When the CO2, O2 and HSS are maintained below critical values, a low carbon structural steel having a micropolished surface finish displayed improved corrosion resistance.