Rocha, Ines L. D.;da Costa Lopes, Andre M.;Ventura, Sonia P. M.;Coutinho, Joao A. P. published 《Selective Separation of Vanillic Acid from Other Lignin-Derived Monomers Using Centrifugal Partition Chromatography: The Effect of pH》. The research results were published in《ACS Sustainable Chemistry & Engineering》 in 2022.Safety of 1-Ethyl-3-methyl-1H-imidazol-3-ium chloride The article conveys some information:
In this work, centrifugal partition chromatog. (CPC) assisted by a polyethylene glycol (PEG)/sodium polyacrylate (NaPA) aqueous biphasic system (ABS) was applied in the separation of five lignin-derived monomers (vanillin, vanillic acid, syringaldehyde, acetovanillone, and p-hydroxybenzaldehyde). The influence of the system pH (unbuffered, pH 5, and pH 12) and added electrolytes (inorganic salts or ionic liquids (ILs)) on the compound partition was initially evaluated. The obtained data revealed that ILs induced more adequate partition coefficients (K < 5) than inorganic salts (K > 5) to enable separation performance in CPC, while alk. conditions (pH 12) demonstrated a pos. impact on the partition of vanillic acid. CPC runs, with buffered ABS at pH 12, enabled a selective separation of vanillic acid from other lignin monomers. Under these conditions, a distinct interaction between the top (PEG-rich) and bottom (NaPA-rich) phases of the ABS with the double deprotonated form of vanillic acid is expected when compared to the remaining lignin monomers (single deprotonated). This is an impactful result that shows the pH to be a crucial factor in the separation of lignin monomer compounds by CPC, while only unbuffered systems have been previously studied in the literature. Finally, the recovery of vanillic acid up to 96% purity and further recycling of ABS phase-forming components were approached as a proof of concept through the combination of ultrafiltration and solid-phase extraction steps.1-Ethyl-3-methyl-1H-imidazol-3-ium chloride (cas: 65039-09-0) were involved in the experimental procedure.
1-Ethyl-3-methyl-1H-imidazol-3-ium chloride(cas: 65039-09-0) is an imidazolium chloride ionic liquid that can be used as:a starting material for the preparation of 1-ethyl-3-methylimidazolium chloride/tetrafluoroborate (EMI.Cl.BF4) molten salt for electrochemical studies; a solvent as well as catalyst for the depolymerization of oak wood lignin.Safety of 1-Ethyl-3-methyl-1H-imidazol-3-ium chloride
Reference:
Imidazole – Wikipedia,
Imidazole | C3H4N2 – PubChem