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The study evaluated removal efficiency of 43 pesticides from water by thin-film composite polyamide membrane indigenously prepared by interfacial polymerization of 1,3-phenylenediamine and 1,3,5 trimesoyl chloride coated on asymmetric polysulfone support. Membrane performance was evaluated by gas and liquid chromatography mass spectroscopy determination of multiple pesticides remaining in feed and permeated water following the application of pesticides each @ 0.02, 0.05, and 0.10 mg/L in de-ionized water. The membrane was most efficient in the rejection of persistent organochlorine insecticides, viz. endosulfans (100%), dichlorodiphenyltrichloroethane (95%), and hexachlorocyclohexane (92%). Out of 43 selected pesticides, 33 were removed by > 80%. Size exclusion mass transfer played a significant role for molecules to pass through the membrane as observed for endosulfan isomers, endosulfan sulphate, and difenoconazole with molecular weight > 400. Pesticide rejection was also related to hydrophobicity (Log P). Hydrophobic pesticides with log P > 4.5 were rejected by > 80%, while monocrotophos with less hydrophobicity (log P = − 0.22) exhibited poor rejection (38%). Water flux decreased with an increase in pesticide concentration. The process of pesticide filtration was optimized at 200 psi. The results indicated the potential of the membrane to remove pesticides from water.

The preparative membrane process is a dynamic one and intertwined with the separation arena. As for the progression of technology in membranes, our direction is to prepare polypyrrole interlayer‐based thin‐film composite (TFC) membrane. Polypyrrole shows its attachment ability with polysulfone membranes. The coverings of pores with the polypyrrole entity result in better flux in terms of TFC membranes compared to TFC membranes on polysulfone (Memb‐I). The membranes are characterized by FTIR‐ATR, contact angle, zeta potential, SEM, AFM. Polypyrrole interlayer‐based membrane (Memb‐II) show better flux though it sacrifices salt separation ability compared to Memb‐I. Memb‐II shows a better separation of pesticides (diuron and isoproturon) compared to Memb‐I. Memb‐II provides isoproturon's separation ability (89.52% rejection, 54.9 LMH), whereas, for diuron, it is 78.82%, 53.46 LMH. The antimicrobial property is seen for interlayer polypyrrole‐based TFC membranes.