http://rdf.ncbi.nlm.nih.gov/pubchem/patent/CA-1057303-A
Outgoing Links
| Predicate | Object |
|---|---|
| assignee | http://rdf.ncbi.nlm.nih.gov/pubchem/patentassignee/MD5_a22da5b7dd6ed60a21538e5edb23e051 |
| classificationCPCInventive | http://rdf.ncbi.nlm.nih.gov/pubchem/patentcpc/C07F9-386 |
| classificationIPCInventive | http://rdf.ncbi.nlm.nih.gov/pubchem/patentipc/C07F9-40 http://rdf.ncbi.nlm.nih.gov/pubchem/patentipc/C07F9-38 |
| filingDate | 1976-03-01-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| grantDate | 1979-06-26-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| inventor | http://rdf.ncbi.nlm.nih.gov/pubchem/patentinventor/MD5_5f8220d8c134aa20c9d6e30b4feda675 |
| publicationDate | 1979-06-26-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| publicationNumber | CA-1057303-A |
| titleOfInvention | Process for preparing 1-hydroxy, ethylidene-1,1-diphosphonic acid |
| abstract | TITLE: PROCESS FOR PREPARING 1-HYDROXY, ETHYLIDENE-1,1-DIPHOSPHONIC ACID INVENTOR: S. VAZOPOLOS ABSTRACT OF THE DISCLOSURE A process for preparing 1-hydroxy, ethylidene-1,1-diphosphonic acid, which comprises contacting a phos-phorus trihalide such as phosphorus trichloride with glacial acetic acid in a reaction zone maintained at a temperature of from about 50°C. to about 80°C. while continuously re-moving by-product acetyl halide as formed from the said reaction zone to form a single-phase liquid reaction product, heating said reaction product to a temperature of from 90°C. to 140°C. and reacting therewith acetic anhydride to form a normally solid anhydrous reaction product, and hydrolyzing said product by steam treatment to recover the desired 1-hydroxy, ethylidene-1,1-diphosphonic acid and remove by-product acetic acid. The acetyl halide by-product is recovered by absorbing same in the aqueous by-product acetic acid recovered from the hydrolysis step and thereby recover-ing glacial acetic acid for storage and recycle to the process. The process is adapted for continuous operation. |
| priorityDate | 1975-07-31-04:00^^<http://www.w3.org/2001/XMLSchema#date> |
| type | http://data.epo.org/linked-data/def/patent/Publication |
Incoming Links
Total number of triples: 38.