Silicone rubber is an indispensable insulation material for power equipment and is difficult to degrade naturally, posing a serious threat to the environment. It remains challenging to dispose this alarming amount of waste. In our previous research, a green pyrolysis recycling method was proposed for waste composite insulators. In this article, the experimental device was further improved, and the recycling process was optimised by orthogonal experiments to obtain nanosilica microspheres (NSMs) with higher purity and controllable particle size for the state-of-the-art engineering applications. Firstly, the effect of three factors (calcination temperature, constant-temperature duration, and heating rate) on the particle size of NSMs were investigated by single-factor analysis. ANOVA and response analyses were then used to examine the goodness of fit of the multi-parameter fitting equation and the interaction impact of multiple factors on the particle size. Finally, homogeneous mesoporous NSMs with higher purity (increased from 97% to 99%) and smaller particle size (decreased from 160 to 103 nm were prepared under the guidance of model. The SiO₂-recovery rate of this method was 74.7%, revealing superior economic value.

中文翻译：

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基于正交试验的退役复合绝缘子高纯介孔纳米二氧化硅微球的合成

硅橡胶是电力设备不可缺少的绝缘材料，难以自然降解，对环境构成严重威胁。处理这种数量惊人的废物仍然具有挑战性。在我们之前的研究中，提出了一种废弃复合绝缘子的绿色热解回收方法。本文进一步改进了实验装置，通过正交实验优化了回收工艺，获得了纯度更高、粒径可控的纳米二氧化硅微球（NSMs），用于最先进的工程应用。首先，通过单因素分析研究了三个因素（煅烧温度、恒温持续时间和加热速率）对NSMs粒径的影响。然后使用方差分析和响应分析来检查多参数拟合方程的拟合优度以及多个因素对粒径的相互作用影响。最后，在模型的指导下制备了具有更高纯度（从 97% 增加到 99%）和更小粒径（从 160 减少到 103 nm）的均匀介孔 NSM。_{该方法的2-}回收率为74.7%，具有较高的经济价值。