Recovery of Au nanoparticles (Au NPs) catalysts via bioreduction method has attracted much attention due to its cost‐effective and eco‐friendly. However, it is a great challenge to recover Au NPs by starch due to its poor solubility. Herein, a novel biomolecule, carboxyl corn starch (CCS), exhibited high solubility and low viscosity is successfully fabricated and utilized to reduce HAuCl₄ in the homogeneous phase environment. Effects of CCS concentration on the structure and performances of Au NPs and its loading in the TS‐1 support (Au/TS‐1) are investigated. The results reveal that both the particle size and Au NPs recovery rate increased with the increase of CCS concentration, while the BET data of Au/TS‐1 decreased. The Au/TS‐1 catalyst achieved 353.01 m²g⁻¹ surface area and 0.293 cm³g⁻¹ pore volume with 2.0 ± 0.3 nm average diameter of loaded Au NPs. When this catalyst is employed to catalyze the vapor phase propylene epoxidation with H₂/O₂ mixture, the propylene conversion rate (19.2%) achieved 67% and 5.8 fold increases when in data reported (11.5%) and soluble starch are used as the control, respectively. The study develops a green and facile method for Au recovery via carboxyl starch bioreduction and Au/TS‐1 exhibited significantly improves catalysis of propylene epoxidation.

中文翻译：

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高溶解度羧酸淀粉回收金纳米颗粒及其对丙烯环氧氧化反应的显着改善

通过生物还原法回收Au纳米颗粒（Au NPs）催化剂因其经济高效和生态友好而备受关注。然而，由于淀粉的溶解性差，通过淀粉回收Au NP是一个巨大的挑战。在此，成功地制备了表现出高溶解度和低粘度的新型生物分子羧基玉米淀粉（CCS），并用于在均相环境中还原HAuCl ₄。研究了CCS浓度对金纳米颗粒结构和性能及其在TS-1载体（Au / TS-1）中的负载量的影响。结果表明，随着CCS浓度的增加，粒径和Au NPs的回收率均增加，而Au / TS-1的BET数据则降低。Au / TS-1催化剂达到353.01 m ² g ^-1表面积和0.293 cm ³ g ^-1孔体积，负载Au Au纳米粒子的平均直径为2.0±0.3 nm。当使用该催化剂催化H ₂ / O ₂混合物气相丙烯环氧化时，丙烯转化率（19.2％）达到67％，当报告的数据为11.5％时，丙烯转化率提高5.8倍，可溶性淀粉用作催化剂。控制。该研究开发了一种绿色便捷的方法，可通过羧基淀粉生物还原来回收金，而Au / TS-1则可显着改善丙烯环氧化的催化作用。