Described are methods and composition for inhibiting polymerization of a monomer (e.g., styrene) composition using an aminated quinone antipolymerant, such as an aminated benzoquinone or aminated naphthoquinone antipolymerant having one or more secondary or tertiary amine group(s). The aminated quinone antipolymerant can be used with little or no nitroxyl group containing antipolymerant yet still provide excellent antipolymerant activity in a monomer-containing composition.

Described are methods and composition for inhibiting polymerization of a monomer (e.g., styrene) composition using an aminated quinone antipolymerant, such as an aminated benzoquinone or aminated naphthoquinone antipolymerant having one or more secondary or tertiary amine group(s). The aminated quinone antipolymerant can be used with little or no nitroxyl group containing antipolymerant yet still provide excellent antipolymerant activity in a monomer-containing composition.

Catalytic methods for synthesis of super linear alkenyl arenes and alkyl arenes are provided. The methods are capable of synthesizing super linear alkyl and alkenyl arenes from simple arene and olefin starting materials and with high selectivity for linear coupling. Methods are also provided for making a 2,6-dimethylnapthalene (DMN) or 2,6-methylethylnapthalene (MEN).

Catalytic methods for synthesis of super linear alkenyl arenes and alkyl arenes are provided. The methods are capable of synthesizing super linear alkyl and alkenyl arenes from simple arene and olefin starting materials and with high selectivity for linear coupling. Methods are also provided for making a 2,6-dimethylnapthalene (DMN) or 2,6-methylethylnapthalene (MEN).

The present disclosure relates to a method of decomposing a phenolic by-product, including: a step of feeding and thermally cracking a phenolic by-product stream to and in a decomposition apparatus, recovering an active ingredient from a top discharge stream, and discharging a high-boiling substance through a bottom discharge stream; a step of pressurizing each of a side discharge stream of the decomposition apparatus and a bottom discharge stream of the decomposition apparatus; a step of mixing the pressurized side discharge stream of the decomposition apparatus and the pressurized bottom discharge stream of the decomposition apparatus with each other to form a mixed stream; and a step of passing a part of the mixed stream through a reboiler, circulating the part of the mixed stream to the decomposition apparatus, and discharging a residual mixed stream.

The present disclosure relates to a method of decomposing a phenolic by-product, including: a step of feeding and thermally cracking a phenolic by-product stream to and in a decomposition apparatus, recovering an active ingredient from a top discharge stream, and discharging a high-boiling substance through a bottom discharge stream; a step of pressurizing each of a side discharge stream of the decomposition apparatus and a bottom discharge stream of the decomposition apparatus; a step of mixing the pressurized side discharge stream of the decomposition apparatus and the pressurized bottom discharge stream of the decomposition apparatus with each other to form a mixed stream; and a step of passing a part of the mixed stream through a reboiler, circulating the part of the mixed stream to the decomposition apparatus, and discharging a residual mixed stream.

Inhibitor compositions for abating undesirable polymerization in the vapor space during purification of reactive vinylic monomers are provided. The polymerization inhibitor compositions include at least a first inhibitor compound having a stable nitroxide radical and a second inhibitor including phenylenediamine. Methods of inhibiting the polymerization of monomers in the vapor-space using the compositions of the disclosure are also provided.

Inhibitor compositions for abating undesirable polymerization in the vapor space during purification of reactive vinylic monomers are provided. The polymerization inhibitor compositions include at least a first inhibitor compound having a stable nitroxide radical and a second inhibitor including phenylenediamine. Methods of inhibiting the polymerization of monomers in the vapor-space using the compositions of the disclosure are also provided.

Inhibitor compositions for abating undesirable polymerization during processing of hydrocarbon stream laden with reactive vinylic monomers are provided. The polymerization inhibitor compositions include at least a first inhibitor compound having a stable nitroxide radical and a second inhibitor including phenylenediamine. Methods of inhibiting the polymerization of monomers using the compositions of the disclosure are also provided. The methods of inhibiting polymerization of monomers include a step of adding a composition of the disclosure to the monomer. In some instances, the monomer is an ethylenically unsaturated monomer. Such ethylenically unsaturated monomers include, but are not limited to, vinyl acetate, acrylonitrile, acrylates, methacrylates, 1,3-butadiene, styrene, isoprene, (meth)acrylic acid, and combinations thereof. Methods of preparing the polymerization inhibitors and compositions of the disclosure are also provided.

Inhibitor compositions for abating undesirable polymerization during processing of hydrocarbon stream laden with reactive vinylic monomers are provided. The polymerization inhibitor compositions include at least a first inhibitor compound having a stable nitroxide radical and a second inhibitor including phenylenediamine. Methods of inhibiting the polymerization of monomers using the compositions of the disclosure are also provided. The methods of inhibiting polymerization of monomers include a step of adding a composition of the disclosure to the monomer. In some instances, the monomer is an ethylenically unsaturated monomer. Such ethylenically unsaturated monomers include, but are not limited to, vinyl acetate, acrylonitrile, acrylates, methacrylates, 1,3-butadiene, styrene, isoprene, (meth)acrylic acid, and combinations thereof. Methods of preparing the polymerization inhibitors and compositions of the disclosure are also provided.