초록 ▼

Hydrocarbon feedstocks containing relatively high levels of nitrogen contaminants are converted by catalytic cracking to products of lower average molecular weight by contacting the feedstock with a mixture of a cracking catalyst and separate particles of a nitrogen scavenger. The nitrogen scavenger

Hydrocarbon feedstocks containing relatively high levels of nitrogen contaminants are converted by catalytic cracking to products of lower average molecular weight by contacting the feedstock with a mixture of a cracking catalyst and separate particles of a nitrogen scavenger. The nitrogen scavenger is a particulate solid acid capable of sorbing pyridine at room temperature and retaining greater than about 5 weight percent of the sorbed pyridine after heating in a vacuum to about 300°C. Examples of the nitrogen scavengers that can be used in the process include amorphous aluminosilicates, nonzeolitic molecular sieves such as pillared clays and delaminated clays, and zeolitic molecular sieves.

대표청구항 ▼

A process for the catalytic cracking of a hydrocarbon feedstock containing nitrogen compounds in an amount such that said feedstock contains greater than about 0.08 weight percent total nitrogen, calculated as the element, which process comprises contacting said feedstock in the vapor phase, without

A process for the catalytic cracking of a hydrocarbon feedstock containing nitrogen compounds in an amount such that said feedstock contains greater than about 0.08 weight percent total nitrogen, calculated as the element, which process comprises contacting said feedstock in the vapor phase, without first treating said feedstock to remove at least a portion of said nitrogen compounds, with a mixture of a regenerated cracking catalyst and separate particles of a nitrogen scavenger under cracking conditions in the substantial absence of added molecular hydrogen in a cracking zone to convert components of said feedstock into lower molecular weight constituents, wherein said regenerated cracking catalyst comprises a zeolitic molecular sieve having cracking activity dispersed in a matrix and said nitrogen scavenger comprises a nonzeolitic molecular sieve or a heat stable metal compound selected from the group consisting of magnesium, calcium, zirconium, boron, phosphorus and tungsten compounds, and wherein the concentration of metals in said hydrocarbon feedstock is such that the following relationship exists 10[Ni]+[V]+[Fe]is less than about 8.0 where [Ni], [V]and [Fe]are the concentrations of nickel, vanadium and iron, respectively, in parts per million by weight.