1 6 hexanediamine

The polyimide polymer Matrimid^® 5218 (Vantico Inc.), solvent N-methyl-2-pyrrolidinone (NMP, >99.5%, Merck) and non-solvent polyethylene glycol 400 (PEG 400, M_w = 400 g mol⁻¹, Merck) were utilized to fabricate the membrane substrate. 1, 6-Hexanediamine (HDA, >98%) was purchased from Alfa-Aesar to crosslink the substrate. M-phenylenediamine (MPD, >99%), trimesoylchloride (TMC, >98%) and sodium dodecyl sulfate (SDS, >99%) were ordered from Sigma-Aldrich and employed for the interfacial polymerization reaction. LiCl (>99%, Sigma-Aldrich), CA (>99%, Sigma-Aldrich), DEA (>99%, Sigma-Aldrich), PEG 1000 (M_w = 1000 g mol⁻¹, Merck) and methyl palmitate (>97.0%, Tokyo Chemical Industry) were utilized as the draw solutes. Ethanol (HPLC grade), isopropanol (IPA, HPLC grade), and n-hexane (HPLC grade) were ordered from Fisher Scientific and employed as the solvents to evaluate the membrane performance. Tetracycline (≥98.0 %, Sigma-Aldrich) and industrial sample, triglycerides from soybean oil (liquid, GIIAVA Singapore), were used as the model feed solutes. The commercial OSN membrane DuraMem 300 obtained from Evonik was utilized for transport mechanism studies. The deionized (DI) water was produced by a Milli-Q ultrapure water system (Millipore, USA). All chemicals were used as received.