Theoretical study of cascade process and enrichment of 13C

A pilot plant of Type 2-7 stainless steel cascade for enriching highly concentrated 13C by using CO2-di-n-butylamine-triethylamine chemical exchange system was set up. The mathematical model of the multistage trapezoid cascade was established, which describes the function relaion among separation factor α, concentration of raw material xf, flow of each column L, diameter of column D, height of column H, equivalent diameter of packing De', productive rate of cascade P and concentration of products xp. The cascade was run, and the concentrative rate of the cascade speeded up and the separative capacity of the cascade was fully developed. The concentration of 13CO2-products remained more than 93 atom % and up to 99.288 atom % during 150 days of drawing-off of products at 100g 13C/a