公开(公告)号：DE19710449A1

公开(公告)日：1998-09-17

申请号：DE19710449

申请日：1997-03-13

Applicant: BASF AG

Inventor： SCHLAEFER DIETER DR ,  MAUS MICHAEL DR ,  RAULS MATTHIAS DR ,  BAUMANN DIETER

IPC: C01D1/30 ,  C01D1/28

Abstract: Production of crystalline NaOH . 3.5H2O, involves crystallising NaOH.3.5H2O from an aqueous NaOH solution oversaturated with NaOH . 3.5H2O, and removing the crystals using a mechanical solid/liquid separator. The solid/liquid separation occurs under conditions in which crystalline NaOH.3.5H2O can be liberated from the lye residues; the NaCl content of the crystalline NaOH . 3.5H2O being ≤ 100 mg per kg.

公开(公告)号：DE19649681A1

公开(公告)日：1998-06-04

申请号：DE19649681

申请日：1996-11-29

Applicant: BASF AG

Inventor： SCHOENHERR MICHAEL DR ,  RAULS MATTHIAS DR ,  ASCHERL HERMANN ,  LETZELTER THOMAS ,  BAUMANN DIETER ,  POTTHOFF-KARL BIRGIT DR

IPC: C11D1/04 ,  C07C227/42 ,  C07C229/16 ,  C07C229/24 ,  C07C229/22 ,  C11D3/33

Abstract: A method for the preparation of a crystalline solid comprising a glycine-N,N-diacetic acid derivative of formula (I) with a very low hygroscopicity, comprises fixing the water content of the starting material containing (I) at 10-30 wt.% and then carrying out crystallisation: MOOC-CH(R)-N(CH2COOM)2 (I) R = 1-30C alkyl or 2-30C alkenyl (both optionally containing 1-5 OH, formyl, 1-4C alkoxy(carbonyl) or phenoxy groups and/or optionally containing up to 5 non-adjacent O atoms in the chain), alkoxylate groups of formula (II), phenyl-(1-20 C)-alkyl (optionally containing up to 3 1-4C alkyl, OH, carboxyl, sulpho or 1-4C alkoxycarbonyl ring substituents), 5- or 6-membered optionally benzalated heterocyclic ring containing up to 3 N, O or S atoms (optionally containing up to 3 1-4C alkyl, OH, carboxyl, sulpho or 1-4C alkoxycarbonyl substituents) or a group of formula (III): -(CH2)k-O-(A O)m-(A O)n-Y (II) -A-CH(COOM)-N(CH2COOM)2 (III) A , A = 2-4C 1,2-alkylene; Y = H, 1-12C alkyl, phenyl or 1-4C alkoxycarbonyl; k = 1-3; m, n = 0-50; A = 1-12C alkylene or single bond; and M = H, alkali(ne earth) metal or optionally substituted ammonium, with the provision that m+n = at least 4.