Process and apparatus for chemically treating a carbon-containing feedstock

A method for controlling an alkane carbon chain distribution of a product stream obtained from depolymerizing a polymer-based feedstock, the method comprising the steps of:

• selecting a molar ratio between aluminum oxide and silicon oxide of a catalytic support comprising a mixture of aluminum oxide and silicon oxide;
• providing a catalyst comprising at least one transition metal or transition metal sulfide supported on the catalytic support having the selected molar ratio between aluminum oxide and silicon oxide;
• selecting a temperature in the range of 200 to 500° C. to carry out the depolymerization reaction;
• and
• reacting the polymer-based feedstock and a hydrogen stream in the presence of the catalyst at the selected temperature to generate an alkane-containing product stream, having controlled alkane carbon chain distribution.

A method for selectively converting a polymer-based feedstock to a liquid naphtha or naphtha-like product, comprising:

• reacting a polymer-based feedstock with a hydrogen stream in the presence of a hydrocracking catalyst, in a one-step, hydrocracking reaction, to depolymerize the polymer-based feedstock and form a liquid naphtha or naphtha-like product containing at least 50% by weight of C4-C12 hydrocarbons and no more than 5% by weight of unsaturated hydrocarbons, based on the total weight of the product,
• wherein:
• the hydrocracking catalyst comprises at least one transition metal or transition metal sulfide supported on a catalytic support comprising an aluminum oxide or a mixture of silicon oxide and aluminum oxide at a molar ratio ranging from 5 to 80, and
• the reaction temperature ranges from about 300-450° C. and hydrogen pressure ranges from about 5 to 100 bar.