改性炭化树脂吸附汽油中噻吩及苯并噻吩

Adsorptive performance of modified carbonized resins for thiophene and benzothiophene in fuels

利用弱酸性酚醛系阳离子交换树脂(122型)为炭化前驱体,通过浸渍于Ni2+,Ag+,Cu2+等硝酸盐溶液中进行阳离子交换以负载金属,在N2气氛保护下焙烧使树脂炭化,并利用CO2气体对炭化树脂进行高温活化改性,制备得到负载金属改性炭化树脂(MCRs)。通过TG-DTA,FT-IR,XRD,SEM等表征分析,表明在620℃焙烧温度下,制得改性炭化树脂球形结构保持完好,树脂表面具有对噻吩类化合物吸附有利的酸性基团,负载金属呈单质微晶态分布。考察改性炭化树脂在常温常压下对模拟汽油中噻吩(T)及苯并噻吩(BT)的吸附性能,负载金属种类影响按吸附容量大小依次为Cu>Ag>Ni,适宜活化温度850℃、活化时间1—2 h,噻吩及苯并噻吩在改性炭化树脂上同时发生物理吸附及π键络合吸附,苯并噻吩的饱和吸附容量更大。

Weak acidic phenolic cation exchange resin （ 122 ） was used as carbon precursor to prepare modified carbonized resins （MCRs）. The materials were modified by Ni2＋ , Ag ＋ and Cu2＋ cation exchange in their nitrate solution, then carbonized by calcinations in N2 atmosphere and activated with CO2. The adsorbents were characterized by TG-DTA, FT-IR, XRD and SEM analysis, and the results reveal that under the calcination temperature 620℃, the MCRs can keep resin＇s spherical appearance well. There are many acidic groups on the surface of MCRs, which are favor of adsorption of thiophenic sulfur. Cation is reduced to metal and dispersed uniform metallic crystals, and the adsorption data indicate that the type of metal loaded affects the adsorption capacity of MCRs for thiophene （T） and benzothiophene （BT） in model gasoline （MG） at normal temperatures and pressures by the order of Cu 〉 Ag 〉 Ni. The optical activation temperature is 850 ℃ , and the favorable activation time is 1 h for thiophene, 2 h for benzothiophene, respectively. Thiophene and benzothiophene are adsorbed on MCRs through both physical adsorption and ~r complexation quasi chemical adsorption, and benzothiophene is easier to be adsorbed on MCRs than thiophene.