The catalytic cracking of C₄₊hydrocarbons is a technology to produce light olefins(ethylene and propylene) with C₄₊hydrocarbons as raw materials. The technology, which uses the fluidized-bed process and zeolite-based catalysts, has the following features: (1) The special pretreatment of raw materials is not necessary; (2) the application range is wide for the raw materials; (3) the product scheme can be adjusted flexibly according to the composition of raw materials and the demand of users.

The pilot-plant test with a scale of 1,000 t/a has been completed, and the corresponding scientific and technologic achievement passed the national identification organized by China Petroleum and Chemical Industry Federation. The expert group appraises thatthe technology developed is with independent intellectual property rights, strong innovation and the international advanced level. This technology has the following technical features: fluidized bed process; conversion of C₄olefins per pass, 72%; conversion of C₄alkane per pass, 17%; yield of ethylene and propylene per pass, 58%; ratio of propylene to ethylene, 1.9%.

This technology uses the C₄fractions to produce ethylene and propylene, which relieves the shortage of light olefins (ethylene and propylene), and improves the utilization value of C₄fractions and the economic benefits of enterprises. This catalytic cracking technology can be used to build a new unit or revamp an existing plant.