Carbon　nanomaterials　were　prepared　using　two-group　arc　discharge　plasma　method　in　this　study.　A　combination　of　an　alternating　current　(AC)　arc　discharge　plasma　and　a　direct　current　(DC)　arc　discharge　plasma　in　a　fluidized　bed　was　used,　in　which　propane　was　cracked　into　carbon　blacks　(CB)　with　controlled　structure　and　hydrogen.　The　effects　of　parameters　such　as　electrode　type,　frequency　of　AC　arc　discharge,　current　of　DC　arc　discharge　and　gas　flow　ratio　(propane/argon)　on　the　synthesis　and　properties　of　CB　were　investigated.　A　systematic　study　of　the　size,　morphology,　microstructure　and　surface　chemical　composition　of　CB　was　conducted　using　various　characterization　techniques.　By　using　this　process,　spherical　and　hydrophobic　CB　with　a　narrow　size　distribution,　high　degree　of　graphitization　and　large　specific　surface　area　were　produced　under　optimal　experimental　conditions.　Then,　as-prepared　CB　were　used　to　adsorb　heavy-metal　ions　in　water　and　to　reinforce　the　engineering　plastic.　The　results　verified　that　the　adsorption　rate　of　the　Cr　(VI)　ion　was　increased　significantly　and　that　the　CB　enhanced　the　electrical　and　mechanical　properties　of　acrylonitrile-butadiene-styrene　(ABS)/natural　rubber　(NR)　composites.　©　2016　Elsevier　B.V.