Kerosine (Petroleum), Hydrodesulfurized

Kerosine (petroleum), hydrodesulfurized (CAS 64742-81-0) is a refined petroleum fraction in the C9–C16 range, produced by catalytic hydrodesulfurization to reduce sulfur content relative to standard kerosene. In automotive cleaning products it serves as a co-solvent alongside aromatic naphthas, adding penetrating and carrying capacity without the higher aromatic content that drives regulatory classification.

At 3–5% concentration in carburetor cleaners, it contributes to the overall solvent load and is present primarily as a processing aid — an aliphatic carrier that improves the formula's ability to wet and flush petroleum deposits. Its ACGIH-assigned skin designation means it can be absorbed dermally, though at the concentrations in finished products this is a minor exposure pathway compared to inhalation during spray application.

The hydrodesulfurized grade is preferred over standard kerosene in consumer formulations because reduced sulfur content lowers catalyst-poisoning risk when the product contacts engine components equipped with oxygen sensors.