Process for the manufacture of aminopolyalkylenephosphonic acid compounds
US7884248B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 7, 2005 |
| Grant date | Feb 8, 2011 |
| Priority date | — |
| Expiry date | Nov 7, 2025 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC07F9/3817
- WIPO fieldOrganic fine chemistry
- WIPO sectorChemistry
Abstract
A beneficial method for the manufacture of amino polyalkylene phosphonic acids, under substantial absence of hydrohalogenic acid, is disclosed. The method, in essence, is based on reacting narrowly defined ratios of phosphorous acid, an amine, a formaldehyde in presence of specific ranges of an acid catalyst having a pKa equal or inferior to 3.1. The inventive method is capable of yielding economically and quality operational/capacity advantages, in particular significantly reduced one-step cycle duration under exclusion, of corrosion disadvantages and also is environmentally friendly without requiring, in that respect, anything more than nominal capital expenditures.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.