Valorizing solid waste for heavy metal adsorption is highly desirable to avoid global natural resources depletion. In this study, we developed a new protocol to valorize Radix Astragali residue (one of the Chinese medicine residues) into a low-cost, chemically robust, and highly permeable (ca. 90%) amino-laced porous double-network hydrogel (NH₂-CNFs/PAA) for efficient Pb(II) adsorption. The NH₂-CNFs/PAA showed (i) excellent Pb(II) adsorption capacity (i.e., 994.5 mg g⁻¹, ~4.8 mmol g⁻¹), (ii) fast adsorption kinetics (k_f = 2.01 ×10⁻⁵ m s⁻¹), (iii) broad working pH range (2.0–6.0), and (iv) excellent regeneration capability (~15 cycles). (v) excellent performance in various real water matrices on Pb(II) removal. Moreover, its high selectivity (distribution coefficient K_d ~2.4 ×10⁶ mL g⁻¹) toward Pb(II) was owing to the present of abundant amino groups (-NH₂). Furthermore, the fix-bed column test indicated the NH₂-CNFs/PAA can effectively remove 114.6 bed volumes (influent concentration ~5000 μg L⁻¹) with an enrichment factor 10.9. The full-scale system modeling (i.e., pore surface diffusion model (PSDM)) has been applied to predict the NH₂-CNFs/PAA performance on Pb(II) removal. Overall, we have provided an alternative “win-win” scenario that can resolve the Chinese medicine residues disposal issue by valorizing it into high performance gel-based adsorbents for efficient heavy metal removal.

为了避免全球自然资源枯竭，非常需要对用于重金属吸附的固体废物进行估价。在本研究中，我们开发了一种新方案，将黄芪残渣（一种中药残渣）转化为低成本、化学稳定性和高渗透性（约90%）的氨基多孔双网络水凝胶（NH ₂ -CNFs/PAA) 用于有效吸附 Pb(II)。NH ₂ -CNFs/PAA表现出(i)优异的Pb(II)吸附能力(即994.5 mg g ^-1，~ 4.8 mmol g ^-1 )，(ii)快速吸附动力学( k _f = 2.01 ×10 ^-5米秒^-1)，(iii) 广泛的工作 pH 范围 (2.0–6.0)，和 (iv) 出色的再生能力（约 15 个循环）。(v) 在各种真实水基质中对 Pb(II) 的去除性能优异。此外，它对Pb(II)的高选择性（分布系数K _d ~2.4 ×10 ⁶ mL g ^-1）是由于存在丰富的氨基（-NH ₂）。此外，固定床柱测试表明NH ₂ -CNFs/PAA可以有效去除114.6床体积（进水浓度~5000 μg L ^-1），富集因子为10.9。全尺寸系统建模（即孔表面扩散模型（PSDM））已应用于预测NH ₂-CNFs/PAA 去除 Pb(II) 的性能。总体而言，我们提供了另一种“双赢”方案，可以通过将中药残留物转化为高效去除重金属的高性能凝胶吸附剂来解决中药残留物处理问题。