Reactive membranes for groundwater remediation of chlorinated aliphatic hydrocarbons: competitive dechlorination and cost aspects

•Reactive membranes degraded 92% of contaminants at 1.7 s residence time.•The Fen+ from Fe0 corrosion was captured by –COOH for in-situ regeneration.•Cost lowers 13.9% vs. granular activated carbon in work breakdown structure model.•The competitive dechlorination decreased the ksa by 28.2–79.2%.•Nanofiltration layer enhanced ŋdechlorin by 54.5% via selective rejection.