劣质煤矸石合成4A沸石分子筛  

Synthesis of 4A Molecular Sieves from Poor Quality Coal Gangue

作　　者：孔德顺[1] 连明磊[1] 范佳鑫[1] 李琳[1] 

机构地区：[1]六盘水师范学院化学与化工系,六盘水553004

出　　处：《中国陶瓷》2013年第6期37-39,43,共4页China Ceramics

基　　金：六盘水市煤系固体废弃物资源化利用创新团队资助(52020-2012-04-01-02);贵州省教育厅重点科研项目资助(2011年度);贵州省煤炭资源清洁高效利用科研实验平台资助(黔科平台[2011]4003);煤系固体废弃物资源化利用实验室(黔教高发:2011-278)

摘　　要：为了利用高铁高砂型劣质煤矸石来合成4A沸石分子筛,先将该煤矸石在350℃煅烧2 h,然后加入过量10%的浓度为20%的盐酸,在90℃的条件下酸浸3 h,除铁率为95.1%,铝元素浸出率为总铝含量的10%;将除铁后的煤矸石粉在750℃煅烧2 h后,煤矸石中的炭等有机质被除去、高岭石转变为无定形态的偏高岭石;然后向该750℃煤矸石煅烧粉中按照m(煤矸石)∶m(氢氧化钠)=1∶1的比例加入氢氧化钠,混匀后在400℃恒温2 h,煅烧粉中的石英等成分转变为可溶于水的硅酸钠和硅铝酸钠,因此获得了高活性的原料;合成4A沸石分子筛的体系组成为n(SiO2)/n(A12O3)=2.0、n(Na2O)/n(SiO2)=1.7、n(H2O)/n(Na2O)=45,该体系先在40℃老化2 h,然后在95℃水热晶化4 h,最后运用XRD及SEM等手段对晶化产物进行了表征,结果表明:产物为纯净的4A沸石分子筛、晶形完好、平均粒径约为1μm、Ca2+交换量为296 mg CaCO3/g干沸石。In order to synthesize 4A molecular sieves from poor quality high iron and silica concentrations coal gangue, the gangue was calcined at 350℃for 2 h, then the hydrochloric acid whose concentration was 20% was added into the metakaolin overdose in 10% and leached at 90 ℃ for 2 h, the iron leaching ratio was 95.1%, the alumina leaching ratio was 10% of the total; the removed iron gangue was calcined at 750 ℃ for 2 h, the carbon and other organic matter were removed and the kaolin transformed into amorphous metakaolin; the sodium hydroxide was added to the 750 ℃ calcined gangue powder with the ratio m（gangue） ： re（sodium hydroxide） =1 ： 1, then the mixture was calcined at 400 ℃ for 2 h, quartz and other matters turned into soluble sodium silicate and sodium aluminosilicate, so the high activity raw material were obtained, then the synthesis system of 4A molecular sieves was formed by n（SiO2）/n（A1203）=2.0, n（Na20）/n（SiO2）=1.7 and n（H20）/n（Na20）=45, the system was aging at 40 ℃ for 2 h, crystallization by hydrothermal method at 95 ℃ for 4 h, the crystal products were characterized by XRD, SEM and other method, the results showed that the products were pure 4A molecular sieves with complete crystal form, the average particle size was at about 1 μm, the Ca2＋ exchange capacity was 296 mg CaCO3/g dry zeolite.

关 键 词：煤矸石 除铁 活化 水热合成 4A沸石分子筛 

分 类 号：TB383[一般工业技术—材料科学与工程]