Bp Chemicals Limited

Placoplatre

Alain Pinede

Christian Sait

Yves Benkemoun

Jacques Heritier

Gacam Benazzouz

Eric Arrivat

Yves Hamelin

Aurélie Peraudeau

Christine Laroulandie

Rosa Casals

Nadia Maimouni

Patrick Rosique

Fabien Peyrat

Pierre Marie Duriaud

Alexandre Fritsch

Marc Antoine Verhaeghe

Aurelie Peraudeau

Emmanuel Geeraert

Jacques Denimal

David Defendenti

The present application relates to a process for the continuous polymerization of isobutene while maintaining at a constant desired value a property P (viscosity or average molecular mass) of the polymer produced. The polymerization is conducted in a reactor comprising a boiling liquid reaction phase which contains the monomer and the polymer being formed, in equilibrium with a gas phase on top of the said liquid phase, by continuous introduction into the reactor of a catalyst and of a C4 hydrocarbon feed mixture comprising the monomer, and by continuous withdrawal from the reactor of the liquid reaction phase, which is subsequently subjected continuously to at least one purification step which is intended to isolate the polyisobutene produced. The process comprises the determination of a target value V of the partial pressure piC4 of the isobutene in the gas phase of the reactor corresponding to the property P, by virtue of an empirical relationship established beforehand between the property P of the polyisobutene produced and piC4. During the polymerization, piC4 is measured and held constant at around the target value V by acting on the flow rate Qc of the catalyst introduced into the reactor and/or on the flow rate Qh of the C4 hydrocarbon feed mixture.

Isobutene polymerization process

Isobutene polymerization process wherein a property P (viscosity or average molecular weight) of the polyisobutene product is maintained constant. The polymerization is conducted continuously in a reactor comprising a boiling liquid reaction phase in equilibrium with a gas phase, by continuous introduction into the reactor of a catalyst and of a C4 hydrocarbon feed mixture comprising the monomer, and by continuous withdrawal from the reactor of the liquid reaction phase. The process comprises the determination of a target value V of the partial pressure, PiC4, of the isobutene in the reactor gas phase corresponding to the desired value of the property P, by virtue of an empirical relationship established beforehand between the property P of the polyisobutene product and PiC4. During the polymerization, PiC4 is measured and a corrected value of PiC4, (PiC4) , is calculated and is held constant at around the target value V, by acting on the flow rate Qc of the catalyst and/or on the flow rate Qh of the C4 hydrocarbon feed mixture.

Growing community of inventors

Ventabren, France

Alain Pinede