This work aims to upcycle mandarin (Citrus reticulum) waste peels into valuable compounds with different applications. The one-factor-at-a-time method was applied to optimize the biosynthesis of silver nanoparticles using the hot water extract of mandarin peels’ waste. The maximum production reached 2.5 g L⁻¹ in a 4-h, pH9, 100 rpm continuous stirring batch process, operating at 30 °C, under fluorescent illumination of 36 W/6400 K, using 3000 mg L⁻¹ extract solution and 2 mmol AgNO₃. Dynamic light scattering, zeta potential, X-ray diffraction, energy-dispersive X-ray, Fourier transform infrared spectroscopy, field emission scanning electron microscope and high-resolution transmission electron microscope were employed to characterize the prepared silver nanoparticles, which revealed highly stable, uniformly distributed, nonagglomerated crystalline silver nanoparticles, with spherical/oval shapes and a size range of 10–19 nm. The preliminary cost analysis proved the cost-effectiveness of the valorization of mandarine peels into silver nanoparticles, which costs approximately 7.6 US$/g green synthesized silver nanoparticles with good savings relative to the global prices of the chemically synthesized ones. Moreover, to reach the point of zero waste and maximize the profitability of the valorization, the mandarin spent waste disposed from the batch process were upcycled to activated carbon which has different applications.

这项工作旨在将普通话（Citrus reticulum）废皮升级为具有不同用途的有价值的化合物。一次单因素方法用于利用柑桔皮废料的热水提取物优化银纳米颗粒的生物合成。在30℃，36 W / 6400 K荧光灯照明下，使用3000 mg L ^-1提取液和2的pH值，在30°C下运行4小时，pH9、100 rpm连续搅拌，最大产量达到2.5 g L ^-1。毫摩尔AgNO ₃。利用动态光散射，ζ电位，X射线衍射，能量色散X射线，傅立叶变换红外光谱，场发射扫描电子显微镜和高分辨率透射电子显微镜对所制备的银纳米颗粒进行表征，显示出高度稳定，球形，椭圆形，大小范围为10–19 nm的均匀分布的，非团聚的结晶银纳米颗粒。初步的成本分析证明了将柑桔果皮制成银纳米颗粒的成本效益，该成本约为7.6美元/克绿色合成的银纳米颗粒，相对于化学合成纳米颗粒的全球价格而言，其节省的成本很高。此外，为了达到零浪费的程度并最大程度地发挥增值作用的利润，