Abstract: New macroporous alkylaminophosphonic chelating resins which exhibit excellent mechanical stability and strength and good chemical stability are characterized by having an apparent density of 0.35 to 0.425 g/ml, a granulometry smaller than 0.8 mm, a water retention of 50 to 60 percent in the acid form, a porosity of 800 to 1100 mm.sup.3 g, a total theoretical capacity for the fixation of calcium ions of not greater than 31 g/l of resin in the sodium form and an osmotic resistance such that more than 90 percent of the beads are intact after 30 shocks. The high resistance to osmotic shock combined with an adequate exchange capacity exhibited by the new resins makes them particularly suitable for use in highly concentrated solutions, such as concentrated electrolytic brines.

Abstract: An apparatus for the continuous production of spherical polymer beads in a restricted size range. Monomer droplets are produced in said size range by subjecting a fine monomer dispersion containing a controlled amount of a surface protective agent to controlled coalescence during passage through a tube (11) under laminar flow conditions. The monomer droplets are delivered from the tube (11) to the top of a polymerizing column (12) of variable cross-section wherein they undergo suspension polymerization in a laminar liquid stream descending through the column. Further polymerization in a separate reactor (30a, 30b) provides the desired polymer beads.

Abstract: A process and apparatus for the continuous production of spherical polymer beads in a restricted size range. Monomer droplets are produced in said size range by subjecting a fine monomer dispersion containing a controlled amount of a surface protective agent to controlled coalescence during passage through a tube (11) under laminar flow conditions. The monomer droplets are delivered from the tube (11) to the top of a polymerizing column (12) of variable cross-section wherein they undergo suspension polymerization in a laminar liquid stream descending through the column. Further polymerization in a separate reactor (30a, 30b) provides the desired polymer beads.

Abstract: Described is an ion exchange resin prepared from a cross-linked vinyl-aromatic polymer carrying recurring active units of the formula --CH.sub.2 NHRPO(OH).sub.2 wherein R is a lower alkylene radical. Such resins are useful in selectively removing metal ions from solutions, and may be prepared, e.g., by reaction of a primary amino-substituted cross-linked copolymer with a phosphorus trihalide and a simple (C.sub.1 -C.sub.3) aldehyde.