Techno-Economic Analysis of Recycled Ionic Liquid Solvent Used in a Model Colloidal Platinum Nanoparticle Synthesis

Ionic
liquids have garnered significant attention over the past
20 years as alternatives to conventional volatile organic solvents
because they are non-flammable, have negligible vapor pressures, possess
high thermal and chemical stabilities, and can potentially be recycled.
A more recent use of ionic liquids is their application as a solvent
in the synthesis of colloidal inorganic nanoparticles; however, a
major challenge in the adoption of ionic liquids is that they are
generally more expensive than their traditional organic solvent counterparts.
Herein, we provide insight into how recycling an ionic liquid solvent
affects the product characteristics in a model colloidal platinum
nanoparticle synthesis, the structure of the ionic liquid through
each recycle, and the overall cost of nanoparticle fabrication using
a techno-economic analysis. Using a standard ionic liquid, 1-butyl-3-methylimidazolium
bis­(trifluoromethylsulfonyl)­imide (BMIM-NTf2), as the solvent
for a Pt nanoparticle synthesis, we demonstrate that the ionic liquid
can be recovered and reused through multiple successive reactions
following the initial reaction with virgin, or as-purchased, ionic
liquid. The use of recycled ionic liquid does not cause any degradation
in the product quality or change in nanoparticle morphology. Techno-economic
analysis of this synthesis method revealed that, through ionic liquid
recycling, nanoparticle preparation using BMIM-NTf2 can
achieve a cost that is not only competitive but also potentially lower
than that of the conventional organic solvent, 1-octadecene.

在过去二十年里，离子液体因其不可燃、蒸气压可忽略不计、具备优异的热稳定性和化学稳定性，以及潜在的回收利用可能性，而作为传统挥发性有机溶剂的替代品，受到了广泛关注。近期，离子液体在作为合成胶体无机纳米颗粒的溶剂方面的应用也日益增多；然而，离子液体在推广应用过程中面临的主要挑战是，其成本通常高于传统的有机溶剂。本研究深入探讨了离子液体溶剂的回收利用对模型胶体铂纳米颗粒产品特性、离子液体结构随每轮回收的变化，以及采用技术经济分析方法制备纳米颗粒的整体成本的影响。以标准离子液体1-丁基-3-甲基咪唑双（三氟甲基磺酰）亚胺（BMIM-NTf2）作为Pt纳米颗粒合成的溶剂，我们证明了离子液体在初始反应后，通过与原装或购买的离子液体进行连续的多轮反应，可以被回收和重复使用。使用回收的离子液体不会对产品质量造成任何退化或改变纳米颗粒的形态。对该合成方法的技术经济分析表明，通过离子液体回收，使用BMIM-NTf2制备纳米颗粒的成本不仅具有竞争力，甚至可能低于传统有机溶剂1-十八烯的成本。