Abstract Over the years, the production of waste ash from many sources (e.g. coal, biomass, industrial, animal, and municipal solid waste) and from conventional and renewable energy technologies has increased, generating environmental problems due to the increasing amount of material disposed of in landfills. Fly ash from coal and biomass represent the foremost waste products produced by fossil fuel combustion and alternative natural energy sources, respectively. These waste materials are most widely utilized in agricultural applications, soil stabilization, and the cement and concrete industries. Among the various methods proposed for the reuse of fly ash, conversion to zeolite offers the greatest benefits; the process diverts ash waste materials from disposal sites and transforms them into useful secondary products for applications ranging from environmental mitigation to catalysis. The vast amount of literature on fly ash application is the fruit of growing waste production and the consequent need to find innovative methods to reduce the amount of waste deposited in landfills. This article summarizes studies concerning both coal and biomass fly ash. The characterization and potential applications of these materials are analysed in detail through reference to the numerous studies published on fly ash worldwide over the last number of decades. A considerable number of experiments have been conducted using ash as a raw material for zeolite synthesis, and many others concern the utilization of the newly-formed mineral. This paper discusses the key factors affecting zeolite synthesis, primarily from coal fly ash; the drawbacks of each approach are also analysed.

中文翻译：

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煤和生物质粉煤灰的最新应用：关注沸石合成工艺和问题

摘要 多年来，来自多种来源（例如煤、生物质、工业、动物和城市固体废物）以及传统和可再生能源技术产生的废灰不断增加，由于处理的材料数量不断增加，产生了环境问题。在垃圾填埋场。来自煤和生物质的飞灰分别代表了化石燃料燃烧和替代自然能源产生的最重要的废物。这些废料最广泛地用于农业应用、土壤稳定以及水泥和混凝土行业。在为再利用粉煤灰提出的各种方法中，转化为沸石的好处最大；该过程将垃圾废物从处置场转移出来，并将其转化为有用的次级产品，用于从环境缓解到催化等各种应用。大量关于粉煤灰应用的文献是垃圾产量不断增加的成果，因此需要找到创新方法来减少垃圾填埋场的垃圾量。本文总结了关于煤和生物质飞灰的研究。这些材料的特性和潜在应用通过参考过去几十年在世界范围内发表的大量关于粉煤灰的研究进行了详细分析。已经使用灰分作为沸石合成的原料进行了大量实验，许多其他实验涉及新形成的矿物的利用。本文讨论了影响沸石合成的关键因素，主要来自粉煤灰；还分析了每种方法的缺点。