FIELD: chemistry.
SUBSTANCE: invention relates to a method for combined processing of high-boiling products and methyldihydropyran, which are by-products of the process of producing isoprene from isobutylene and formaldehyde, by mixing feedstock with steam and then contacting on an aluminosilicate-containing catalyst at high temperature. The method is characterised by that a methyldihydropyran fraction is first evaporated at 155-165°C, followed by heating in the presence of steam with the ratio of steam to the methyldihydropyran fraction equal to (0.5-3.0):1, at 400-550°C; high-boiling products are mixed with steam without further heating and then fed along with the heated methyldihydropyran fraction for decomposition at 450-550°C.
EFFECT: method increases conversion of the heavy residue and reduces coke deposit.
4 ex, 1 tbl
