ICN2 (CSIC & BIST), Campus UAB, Bellaterra, 08193 Barcelona, Spain.
ICN2 (CSIC & BIST), Campus UAB, Bellaterra, 08193 Barcelona, Spain.
J Colloid Interface Sci. 2021 May;589:500-510. doi: 10.1016/j.jcis.2020.12.067. Epub 2020 Dec 24.
Nanoparticles removal from seawage water is a health and environmental challenge, due to the increasing use of these materials of excellent colloidal stability. Herein we hypothesize to reach this objective through complex coacervation, a straightforward, low-cost process, normally accomplished with non-toxic and biodegradable macromolecules. Highly dense polymer-rich colloidal droplets (the coacervates) obtained from a reversible charge-driven phase separation, entrap suspended nanomaterials, allowing their settling and potential recovery.
In this work we apply this process to highly stable aqueous colloidal dispersions of different surface charge, size, type and state (solid or liquid). We systematically investigate the effects of the biopolymers excess and the nanomaterials concentration and charge on the encapsulation and sedimentation efficiency and rate. This strategy is also applied to real laboratory water-based wastes.
Long-lasting colloidal suspensions are succesfully destabilized through coacervate formation, which ensures high nanomaterials encapsulation efficiencies (~85%), payloads and highly tranparent supernatants (%T ~90%), within two hours. Lower polymer excess induces faster clearance and less sediments, while preserving effective nanomaterials removal. Preliminary experiments also validate the method for the clearance of real water residuals, making complex coacervation a promising scalable, low-cost and ecofriendly alternative to concentrate, separate or recover suspended micro/nanomaterials from aqueous sludges.
由于具有出色胶体稳定性的这些材料的使用越来越多，因此从海水中去除纳米颗粒是一个健康和环境挑战。在此，我们假设通过复凝聚达到这一目标，这是一种简单、低成本的工艺，通常使用无毒且可生物降解的大分子来完成。通过可逆的电荷驱动相分离获得的高度致密的富含聚合物的胶体液滴（凝聚物）会捕获悬浮的纳米材料，从而允许它们沉降和潜在回收。
在这项工作中，我们将该工艺应用于具有不同表面电荷、尺寸、类型和状态（固体或液体）的高度稳定的水性胶体分散体。我们系统地研究了生物聚合物过量以及纳米材料浓度和电荷对封装和沉淀效率和速率的影响。该策略还应用于实际的实验室水基废物。
通过凝聚物形成成功地使持久的胶体悬浮液不稳定，这确保了高纳米材料封装效率（约 85%）、有效去除纳米材料。当聚合物过量较低时，会导致更快的清除和更少的沉淀物，同时保持有效的纳米材料去除。初步实验还验证了该方法对实际水残余物的清除效果，使复凝聚成为一种有前途的可扩展、低成本且环保的替代方案，可用于浓缩、分离或从水污泥中回收悬浮的微/纳米材料。
