Abstract: A method for preparing a purified styrene composition with a styrene yield of at least 80%. The method comprises providing a crude composition containing styrene, and subjecting the crude composition to at least one crystallization step. The at least one crystallization step comprises at least one static crystallization stage and at least one dynamic crystallization stage.

Abstract: A method for preparing a purified styrene composition is provided. The method includes providing a crude composition and subjecting the crude composition to at least one crystallization step. The crude composition contains 70% by weight or more styrene based on the total weight of the crude composition. The at least one crystallization step comprises at least one of a static crystallization stage and a dynamic crystallization stage. The crude composition contains at least one impurity selected from the group consisting of: color inducing species, oxygenates, sulfur species, alpha-methylstyrene, and mixtures thereof.

Abstract: A method for preparing a purified styrene composition with a styrene yield of at least 80%. The method comprises providing a crude composition containing styrene, and subjecting the crude composition to at least one crystallization step. The at least one crystallization step comprises at least one static crystallization stage and at least one dynamic crystallization stage.

Abstract: A method for preparing a purified styrene composition with a styrene yield of at least 80%. The method comprises providing a crude composition containing styrene, and subjecting the crude composition to at least one crystallization step. The at least one crystallization step comprises at least one static crystallization stage and at least one dynamic crystallization stage.

Abstract: A method for preparing a purified styrene composition is provided. The method includes providing a crude composition and subjecting the crude composition to at least one crystallization step. The crude composition contains 70% by weight or more styrene based on the total weight of the crude composition. The at least one crystallization step comprises at least one of a static crystallization stage and a dynamic crystallization stage. The crude composition contains at least one impurity selected from the group consisting of: color inducing species, oxygenates, sulfur species, alpha-methylstyrene, and mixtures thereof.

Abstract: In various embodiments, the present disclosure describes methods for removing impurities from a hydrocarbon stream containing at least one vinyl aromatic compound such as, for example, styrene. The methods include pretreating at least one sorbent to make the at least one sorbent operable for adsorbing the impurities, contacting the hydrocarbon stream with the at least one sorbent in order to adsorb at least a portion of the impurities and separating the hydrocarbon stream from the at least one sorbent. Impurities include, for example, colored impurities, sulfur-containing impurities and combinations thereof.

Abstract: In various embodiments, the present disclosure describes methods for removing impurities from a hydrocarbon stream containing at least one vinyl aromatic compound such as, for example, styrene. The methods include pretreating at least one sorbent to make the at least one sorbent operable for adsorbing the impurities, contacting the hydrocarbon stream with the at least one sorbent in order to adsorb at least a portion of the impurities and separating the hydrocarbon stream from the at least one sorbent. Impurities include, for example, colored impurities, sulfur-containing impurities and combinations thereof.

Abstract: A method and apparatus for purifying carboxylic acids is disclosed. A mixture containing crude carboxylic acid is contacted with a selective crystallization solvent to form a slurry of a salt complex of the carboxylic acid and the selective crystallization solvent. The salt complex is recovered and optionally processed to recover the free carboxylic acid. The method and apparatus of the invention is particularly suitable for purifying aromatic dicarboxylic acids such as terephthalic acid. The present invention also reduces contamination by carboxybenaldehyde isomers in crude phthalic acids by oxidizing the carboxybenzaldehyde to the corresponding phthalic acid.