Method and catalyst system for producing aromatic carbonates

A method of carbonylating an aromatic hydroxy compound, said method comprising the step of:

• contacting at least one aromatic hydroxy compound with oxygen and carbon monoxide in the presence of a carbonylation catalyst system comprising catalytic amounts of the following components:
• a Group VIII B metal source;
• a combination of inorganic co-catalysts including a copper source and at least one of a titanium source or a zirconium source;
• an onium chloride composition;
• and
• a base.

A carbonylation catalyst system, comprising catalytic amounts of the following components:

• a Group VIII B metal source;
• a combination of inorganic co-catalysts including a lead source and at least one of a titanium source or a manganese source;
• an onium chloride composition;
• and
• a base.

A carbonylation catalyst system, comprising catalytic amounts of the following components:

• a Group VIII B metal source;
• a combination of inorganic co-catalysts including a copper source and at least one of a titanium source or a zirconium source;
• an onium chloride composition;
• and
• a base.