求翻译：ZSM-5分子筛的主要功能是有选择性地把一些裂化生成的、辛烷值很低的正构C7～C13烷烃或带一个甲基侧链的烷烃和烯烃进行选择性裂化生成辛烷值高的C3～C5烯烃，而且C4、C5异构物比例大，从而提高了汽油的辛烷值是什么意思？

ZSM-5 zeolite's main function is to selectively generate some cracking, low octane n-C7 ~ C13 alkane or with a methyl side chain alkanes and alkenes to selectively produce high octane cracking The C3 ~ C5 olefins and C4, C5 isomers ratio, thus, increase the octane level of gasoline

molecular sieve ZSM - 5 The main function is to put some hydrofreezing selectively, with an octane number generated by a very low level of 13 is for alkane C 7~ C or take one of the methyl side chain alkane and olefins on selective catalytic cracking plant generates high octane number of 3 ~ C C C 4

The ZSM-5 molecular sieve main function has selectively some cracking production, the octane value very low is constructing the C7~C13 alkane or brings methyl side chain alkane and the alkene carries on the selective cracking production octane value high C3~C5 alkene, moreover C4, the C5 isomer prop

ZSM-5 molecular sieve's main function is to selectively generate some cracking, low octane number is n C7~C13 n-alkanes or take a methyl side chain n-alkanes and alkenes for selective C3~C5 of high octane number of FCC generates olefin, and C4, C5 isomer ratio, increasing gasoline octane number

The main function that ZSM-5 molecule sifted turned into some cracking selectively, hard alkane value very low to construct C7-C13 alkane hydrocarbon or with a methyl side chain alkane hydrocarbon and alkene carry on alternative cracking produce hard alkane value high C3-C5 alkene, C4, C5 different