Nano　zero-valent　iron　(NZVI)　is　widely　used　for　reducing　chlorinated　organic　pollutants　in　water.　However,　the　stability　of　the　particles　will　affect　the　removal　rate　of　the　contaminant.　In　order　to　enhance　the　stability　of　nano　zero-valent　iron　(NZVI),　the　particles　were　modified　with　F-127　as　an　environmentally　friendly　organic　stabilizer.　The　study　investigated　the　effect　of　the　F-127　mass　ratio　on　the　colloidal　stability　of　NZVI.　Results　show　that　the　sedimentation　behavior　of　F-NZVI　varied　at　different　mass　ratios.　A　biphasic　model　was　used　to　describe　the　two　time-dependent　settling　processes　(rapid　sedimentation　followed　by　slower　settling),　and　the　settling　rates　were　calculated.　The　surface　morphology　of　the　synthesized　F-NZVI　was　observed　with　a　scanning　electron　microscope　(SEM),　and　the　functional　groups　of　the　samples　were　analyzed　with　Fourier　Transform　Infrared　Spectroscopy　(FTIR).　Results　show　that　the　F-127　was　successfully　coated　on　the　surface　of　the　NZVI,　and　that　significantly　improved　the　stability　of　NZVI.　Finally,　in　order　to　optimize　the　removal　rate　of　2,4-dichlorophenol　(2,4-DCP)　by　F-NZVI,　three　variables　were　tested:　the　initial　concentration　2,4-DCP,　the　pH,　and　the　F-NZVI　dosage.　These　were　evaluated　with　a　Box-Behnken　Design　(BBD)　of　response　surface　methodology　(RSM).　The　experiments　were　designed　by　Design　Expert　software,　and　the　regression　model　of　fitting　quadratic　model　was　established.　The　following　optimum　removal　conditions　were　determined:　pH　=　5,　3.5　g　center　dot　L-1　F-NZVI　for　22.5　mg　center　dot　L-1　of　2,4-DCP.