Synthesis of p-Xylene by Dehydroaromatization of 3-Methyleneheptane obtained from Ethylene

TY - PAT

T1 - Synthesis of p-Xylene by Dehydroaromatization of 3-Methyleneheptane obtained from Ethylene

AU - Goldman, Alan

AU - Steffens, Andrew

AU - Schinski, William

PY - 2017/12

Y1 - 2017/12

N2 - Invention Summary: p -Xylene is mostly produced from cracking of naphtha, but there is a need for new and cost-effective methods for the production.  Indeed, conventional p-xylene synthesis requires toluene separation from refinery gasoline streams; performing a disproportionation reaction to yield a benzene fraction and a mixed xylene fraction; and finally an isomerization step over a zeolite catalyst which converts ortho- and meta- xylenes to the para isomer. p -Xylene is then separated in a costly crystallization step from the unconverted ortho and meta isomers which are recycled to the zeolite. Rutgers scientists have developed a new method of preparing p-xylene by dehydroaromatization of 3-methyleneheptane (i.e. 2-ethylhex-1-ene) or 3-methylheptane using pincer-ligated iridium catalysts under relatively mild conditions and with yields of up to 60%. 3-Methyleneheptane can be obtained from the dimerization of butenes.Butenes can in turn can be obtained as refinery products or from the dimerization of ethylene. Market Applications: Petrochemicals Catalysts Advantages: Relatively mild reaction conditions Good yields Ethylene or butene refinery products as feedstock The proposed method is more cost-effective than current methods Intellectual Property & Development Status: Patent pending. This product is available for licensing and/or research collaboration.

AB - Invention Summary: p -Xylene is mostly produced from cracking of naphtha, but there is a need for new and cost-effective methods for the production.  Indeed, conventional p-xylene synthesis requires toluene separation from refinery gasoline streams; performing a disproportionation reaction to yield a benzene fraction and a mixed xylene fraction; and finally an isomerization step over a zeolite catalyst which converts ortho- and meta- xylenes to the para isomer. p -Xylene is then separated in a costly crystallization step from the unconverted ortho and meta isomers which are recycled to the zeolite. Rutgers scientists have developed a new method of preparing p-xylene by dehydroaromatization of 3-methyleneheptane (i.e. 2-ethylhex-1-ene) or 3-methylheptane using pincer-ligated iridium catalysts under relatively mild conditions and with yields of up to 60%. 3-Methyleneheptane can be obtained from the dimerization of butenes.Butenes can in turn can be obtained as refinery products or from the dimerization of ethylene. Market Applications: Petrochemicals Catalysts Advantages: Relatively mild reaction conditions Good yields Ethylene or butene refinery products as feedstock The proposed method is more cost-effective than current methods Intellectual Property & Development Status: Patent pending. This product is available for licensing and/or research collaboration.

M3 - Innovation

ER -