Abstract Recent studies on the exploration of eco-friendly approach by utilizing large-scale waste materials as potential catalyst in biodiesel production have attracted much attention. The development of heterogeneous catalysts especially from calcium has gained much awareness due to the large availability of calcium-rich waste materials and their corresponding high catalytic activity in the transesterification of oil. Most of the waste materials employed as heterogeneous catalysts have an abundance of natural Ca content and they have high catalyst activity and selectivity despite being environment-friendly and cost-effective. Heterogeneous catalysts with high activity can be produced from Ca based waste materials when calcined at high temperatures. This review gives a brief overview of the developments of various Ca based catalysts derived from waste materials as an efficient catalyst for biodiesel production with significant yield. Industrial wastes (red mud, slag, ash) and biological catalysts (chicken eggshells, mollusk shells, animal bones) possess enormous potential towards developing an economical catalyst and subsequently, low-cost biodiesel generation. However, future challenges await a better utilization of useless wastes into a useful resource to satisfy human needs.

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废料作为生物柴油生产的潜在催化剂：现状和未来范围

摘要 近年来，利用大规模废料作为生物柴油生产的潜在催化剂探索生态友好方法的研究引起了广泛关注。由于富含钙的废料的大量可用性以及它们在油的酯交换中相应的高催化活性，开发非均相催化剂，尤其是来自钙的多相催化剂已经得到广泛关注。大多数用作非均相催化剂的废料具有丰富的天然钙含量，尽管它们对环境友好且具有成本效益，但它们具有较高的催化剂活性和选择性。当在高温下煅烧时，可以从基于钙的废料生产具有高活性的多相催化剂。本综述简要概述了从废料中提取的各种 Ca 基催化剂作为生物柴油生产的有效催化剂的发展，并具有显着的产率。工业废物（赤泥、矿渣、灰烬）和生物催化剂（鸡蛋壳、软体动物壳、动物骨头）在开发经济催化剂和随后低成本生物柴油生产方面具有巨大潜力。然而，未来的挑战等待更好地利用无用废物转化为有用资源以满足人类需求。