A continuous flow process and system for depolymerizing plastic. A heterogeneous mixture of solid plastic particles, a solvent, and a catalyst are pumped continuously through a heating zone at a flow rate resulting in a particle speed sufficient to keep the plastic particles in suspension. The heterogeneous mixture is heated in the heating zone and maintained in a hold zone to complete depolymerization of the mixture into a homogeneous solution containing a liquefied reaction product. The homogeneous solution is cooled to solidify and precipitate a solid reaction product. The solid reaction product is separated from the solvent to be recycled. Contaminants are removed from the solvent, and the solvent is recirculated for use as a constituent of the heterogeneous mixture.

Suggested are 1,2-alkanediols of formula (I) HOCH.sub.2—CH(OH)—R.sup.1 in which R.sup.1 stands for an alkyl radical having 3 to 10 carbon atoms, said diols being substantially free of lactones and/or peroxides.

Suggested are 1,2-alkanediols of formula (I) HOCH.sub.2—CH(OH)—R.sup.1 in which R.sup.1 stands for an alkyl radical having 3 to 10 carbon atoms, said diols being substantially free of lactones and/or peroxides.

The present invention relates to a haloalkenyl alkoxymethyl ether compound of the following general formula (1): R.sup.1CH.sub.2OCH.sub.2OCH.sub.2CH.sub.2CH═CH(CH.sub.2).sub.aX.sup.1 (1) wherein R.sup.1 represents a hydrogen atom, an n-alkyl group having 1 to 9 carbon atoms, or a phenyl group, X.sup.1 represents a halogen atom, and “a” represents an integer of 3 to 14. The present invention also relates to processes for preparing a terminal conjugated alkadien-1-yl acetate compound of the following general formula (5): CH.sub.2═CHCH═CH(CH.sub.2).sub.aOAc (5) wherein “a” is as defined above, and Ac represents an acetyl group, and a terminal conjugated alkadien-1-ol compound of the following general formula (6): CH.sub.2═CHCH═CH(CH.sub.2).sub.aOH (6) wherein “a” is as defined above, from the haloalkenyl alkoxymethyl ether compound (1).

The present invention relates to a haloalkenyl alkoxymethyl ether compound of the following general formula (1): R.sup.1CH.sub.2OCH.sub.2OCH.sub.2CH.sub.2CH═CH(CH.sub.2).sub.aX.sup.1 (1) wherein R.sup.1 represents a hydrogen atom, an n-alkyl group having 1 to 9 carbon atoms, or a phenyl group, X.sup.1 represents a halogen atom, and “a” represents an integer of 3 to 14. The present invention also relates to processes for preparing a terminal conjugated alkadien-1-yl acetate compound of the following general formula (5): CH.sub.2═CHCH═CH(CH.sub.2).sub.aOAc (5) wherein “a” is as defined above, and Ac represents an acetyl group, and a terminal conjugated alkadien-1-ol compound of the following general formula (6): CH.sub.2═CHCH═CH(CH.sub.2).sub.aOH (6) wherein “a” is as defined above, from the haloalkenyl alkoxymethyl ether compound (1).

The present invention relates to a haloalkenyl alkoxymethyl ether compound of the following general formula (1): R.sup.1CH.sub.2OCH.sub.2OCH.sub.2CH.sub.2CH═CH(CH.sub.2).sub.aX.sup.1 (1) wherein R.sup.1 represents a hydrogen atom, an n-alkyl group having 1 to 9 carbon atoms, or a phenyl group, X.sup.1 represents a halogen atom, and “a” represents an integer of 3 to 14. The present invention also relates to processes for preparing a terminal conjugated alkadien-1-yl acetate compound of the following general formula (5): CH.sub.2═CHCH═CH(CH.sub.2).sub.aOAc (5) wherein “a” is as defined above, and Ac represents an acetyl group, and a terminal conjugated alkadien-1-ol compound of the following general formula (6): CH.sub.2═CHCH═CH(CH.sub.2).sub.aOH (6) wherein “a” is as defined above, from the haloalkenyl alkoxymethyl ether compound (1).

The present invention relates to a haloalkenyl alkoxymethyl ether compound of the following general formula (1): R.sup.1CH.sub.2OCH.sub.2OCH.sub.2CH.sub.2CH═CH(CH.sub.2).sub.aX.sup.1 (1) wherein R.sup.1 represents a hydrogen atom, an n-alkyl group having 1 to 9 carbon atoms, or a phenyl group, X.sup.1 represents a halogen atom, and “a” represents an integer of 3 to 14. The present invention also relates to processes for preparing a terminal conjugated alkadien-1-yl acetate compound of the following general formula (5): CH.sub.2═CHCH═CH(CH.sub.2).sub.aOAc (5) wherein “a” is as defined above, and Ac represents an acetyl group, and a terminal conjugated alkadien-1-ol compound of the following general formula (6): CH.sub.2═CHCH═CH(CH.sub.2).sub.aOH (6) wherein “a” is as defined above, from the haloalkenyl alkoxymethyl ether compound (1).

Methods for preparation of olefins, including 8- and 11-unsaturated monoenes and polyenes, via transition metathesis-based synthetic routes are described. Metathesis reactions in the methods are catalyzed by transition metal catalysts including tungsten-, molybdenum-, and ruthenium-based catalysts. The olefins include insect pheromones useful in a number of agricultural applications.

Methods for preparation of olefins, including 8- and 11-unsaturated monoenes and polyenes, via transition metathesis-based synthetic routes are described. Metathesis reactions in the methods are catalyzed by transition metal catalysts including tungsten-, molybdenum-, and ruthenium-based catalysts. The olefins include insect pheromones useful in a number of agricultural applications.

The present disclosure relates to the formation of terephthalate esters. The present invention also relates to the depolymerization of polyethylene terephthalate (PET) or poly(ethylene glycol-co-1,4-cyclohexanedimethanol terephthalate) and the recovery of terephthalate esters