粉煤灰基沸石分子筛的合成及应用进展  

Recent progress of synthesis and application of fly ash based zeolite

作　　者：何光耀 王兵[2,3] 史鹏程[1] 鲍卫仁 常丽萍[2,3] 黄张根[4] 王建成[2,3] 韩丽娜[1] HE Guangyao;WANG Bing;SHI Pengcheng;BAO Weiren;CHANG Liping;HUANG Zhanggen;WANG Jiancheng;HAN Li′na(College of Materials Science and Engineering,Taiyuan University of Technology,Taiyuan 030024,China;State Key Laboratory of Clean and Efficient Coal Utilization,Taiyuan University of Technology,Taiyuan 030024,China;Key Laboratory of Coal Science and Technology,Ministry of Education,Taiyuan University of Technology,Taiyuan 030024,China;State Key Laboratory of Coal Conversion,Institute of Coal Chemistry,Chinese Academy of Sciences,Taiyuan 030001,China)

机构地区：[1]太原理工大学材料科学与工程学院,山西太原030024 [2]太原理工大学、省部共建煤基能源清洁高效利用国家重点实验室,山西太原030024 [3]太原理工大学煤科学与技术教育部重点实验室,山西太原030024 [4]中国科学院、山西煤炭化学研究所、煤转化国家重点实验室,山西太原030001

出　　处：《洁净煤技术》2021年第3期48-60,共13页Clean Coal Technology

基　　金：国家自然科学基金面上资助项目(2197081658);煤转化国家重点实验室开放课题资助项目(J20-21-309);山西省高等学校科技成果转化培育项目(2020CG010)。

摘　　要：煤炭在燃烧利用过程中产生大量的粉煤灰。我国粉煤灰产量高居世界第1位,由于综合利用率只有70%,仍有大量粉煤灰露天堆存,造成严重的环境污染和资源浪费。消除粉煤灰的环境污染、提高其资源化利用率对我国循环经济的发展具有重要的现实意义。我国粉煤灰的利用由早期的粗放型规模化利用逐渐向精细型高值化利用转变。由于粉煤灰中富含硅铝元素,以粉煤灰为原料合成沸石分子筛是近年来粉煤灰高值化利用的研究热点。从4个方面对粉煤灰基沸石分子筛的合成及应用展开论述。首先,介绍了粉煤灰的形成、物化性质及其危害和治理利用现状。粉煤灰是一些矿物组成不同、形态不同的颗粒的机械混合物,其性质与原煤的成分、产地和燃烧方式有关。而粉煤灰的特性是决定其综合利用方式的关键。其次,论述了粉煤灰的3种主要活化方式,包括机械活化、水热活化和碱(盐)融活化。粉煤灰中的硅铝元素主要以非晶矿物玻璃体形式存在,其表面是致密的玻璃质外壳,粉煤灰合成沸石分子筛的关键问题是如何使硅和铝被充分活化,并得到有效利用。相比于机械研磨活化和碱(盐)熔融活化,水热活化有更高的活化效率和较低的能耗。第3部分论述了粉煤灰基沸石分子筛放入水热合成方法,重点介绍了直接水热合成法、碱融-水热合成法、微波/超声波-水热合成法、晶种法和转晶法。粉煤灰合成沸石分子筛一般均基于水热合成过程,多步水热处理可提高产物纯度,辅以超声、微波、碱熔融和添加晶种等方法可提高产率、晶化速率和结晶度。转晶法可极大拓展粉煤灰基沸石的骨架类型和酸性位,是更有利的粉煤灰基沸石分子筛的制备技术。最后,概述了粉煤灰基沸石分子筛的应用。粉煤灰基沸石分子筛的应用尚处于探索阶段,主要用于环境治理领域,包括工业废水�A large amount of fly ash is produced in the process of coal combustion.The output of fly ash in China ranks the first in the world.Because the comprehensive utilization rate is only 70%,a large amount of fly ash is still in open storage,resulting in serious environmental pollution and waste of resources.It is of great practical significance to eliminate environmental pollution of fly ash and improve its resource utilization for the development of circular economy in China.The utilization of fly ash in China has gradually changed from the early extensive large-scale utilization to the fine high-value utilization.Since fly ash is rich in silicon and aluminum elements,the synthesis of zeolite molecular sieve from fly ash is a research hotspot in the high-value utilization of fly ash in recent years.In this paper,the synthesis and application of fly ash based zeolite from four aspects were discussed.Firstly,the formation,physical and chemical properties,hazards,treatment and utilization status of fly ash were introduced.Fly ash is a mechanical mixture of particles with different mineral compositions and forms.Its properties are related to the composition,origin and combustion mode of raw coal.The characteristics of fly ash are the key to its comprehensive utilization.Secondly,three main activation methods of fly ash were discussed,including mechanical activation,hydrothermal activation and alkali(salt)melting activation.Silicon and aluminum in fly ash mainly exist in the form of amorphous mineral vitreous,and its surface is a dense glass shell.The key problem in the synthesis of zeolite molecular sieve by fly ash is how to make silicon and aluminum fully activated and effectively utilized.Compared with mechanical grinding activation and alkali(salt)melting activation,hydrothermal activation has higher activation efficiency and lower energy consumption.In the third part,the hydrothermal synthesis methods of fly ash based zeolite were discussed.The direct hydrothermal synthesis method,alkali fusion hydrothermal synthe

关 键 词：粉煤灰 沸石分子筛 水热合成 吸附分离 氮氧化物脱除 重金属脱除 

分 类 号：X773[环境科学与工程—环境工程]