Nanofiltration　(NF)　membranes　have　been　used　previously　for　the　recovery　of　dyes,　salts,　and　water　from　textile　wastewaters　with　high　salinity.　However,　commercially　available　NE　membranes　have　a　high　rejection　for　divalent　salts　(i.e.,　Na2SO4),　substantially　reducing　the　salt　recovery　and　membrane　flux　when　treating　textile　wastewater　containing　Na2SO4.　In　this　study,　a　tight　ultrafiltration　membrane　(UH004,　Microdyn-Nadir)　was　proposed　to　fractionate　the　dye　and　Na2SO4　in　the　textile　wastewater.　The　UH004　membrane　with　a　molecular　weight　cutoff　of　4700　Da　provided　complete　passage　of　monovalent　salts,　with　little　rejection　of　Na2SO4.　This　significantly　increases　the　filtrate　flux　that　can　be　achieved　with　high-salinity　wastewater　since　osmotic　pressure　and　concentration　polarization　effects　are　minimized.　Furthermore,　the　retention　behavior　of　four　different　dyes　was　evaluated　to　determine　the　efficiency　of　this　membrane　process.　This　tight　ultrafiltration　membrane　offered　the　high　retention　for　direct　dyes　(i.e.,　direct　red　80,　direct　red　23,　and　Congo　red)　and　reactive　blue　2.　For　instance,　the　UH004　membrane　yielded　＞　98.9%　rejection　for　all　of　the　dyes　at　a　pressure　of　4　bar　even　in　the　presence　of　60　g　L-1　Na2SO4.　Subsequently,　an　ultrafiltration-diafiltration　process　was　designed　to　separate　a　dye/Na2SO4　aqueous　mixture　with　98%　desalination　efficiency　and　greater　than　97%　dye　recovery　after　5　diavolumes.　These　results　clearly　demonstrate　that　tight　ultrafiltration　membranes　can　be　a　stand-alone　alternative　to　NE　membranes　for　the　effective　fractionation　of　dye　and　Na2SO4　in　the　direct　treatment　of　high-salinity　textile　wastewater.　(C)　2016　Elsevier　B.V.　All　rights　reserved.