Carbon sorbent for removal of metal catalysts from pharmaceuticals

Patent metadata

Field	Value
Publication number	US-11077421-B2
Application number	US-201716128293-A
Country	US
Kind code	B2
Filing date	Mar 24, 2017
Priority date	Mar 28, 2016
Publication date	Aug 3, 2021
Grant date	Aug 3, 2021

Abstract

The present invention relates to a carbon sorbent the can selectively remove platinum-group metals and other heavy metals such as tin without co-removing organic synthesis products including pharmaceutical intermediates and finished Active Pharmaceutical Ingredients (APIs). The carbon sorbents of the present invention are made from low-cost, high purity starting materials and the resulting carbon sorbents are also very pure. The carbon sorbents possess a combination of certain nitrogen and phosphorous groups combined with mesoporosity (2 to 50 nm diameter pores) that proves the high metal adsorption.

First claim

What is claimed is:

1. A carbon sorbent for removing metals from an active pharmaceutical ingredient (API) organic reaction product, the carbon sorbent comprising:
(a) a nitrogen content of at least 3 weight %, which is present in the form of pyridine, pyridone, pyrrole or N—P bonds;
(b) an oxygen content of between 7 weight % and 16 weight %;
(c) a phosphorous content of at least 0.8 atom % as measured by X-ray photoelectron spectroscopy;
(d) a BET surface area of between 200 and 1700 meters squared per gram;
(e) a mesopore volume of at least 0.05 cubic centimeters per gram, wherein mesopores have a diameter of from 2 to 50 nanometers;
(f) a platinum-group metal uptake of at least 83% from a solution of 1.3 ppm platinum-group metal in an organic solvent with an active pharmaceutical ingredient (API) organic reaction product present in the organic solvent at a concentration of 1.0 grams of the active pharmaceutical ingredient (API) organic reaction product per 0.5 grams of the carbon sorbent, and wherein less than 1% of the active pharmaceutical ingredient (API) organic reaction product is adsorbed by the carbon sorbent from the organic solvent simultaneously with the platinum-group metal uptake;
wherein the platinum-group metal is-palladium; and,
(g) a pH of at most 3.1.

2. The carbon sorbent of claim 1 , further comprising: an ash content of at most 1.0 weight %.

3. The carbon sorbent of claim 2 , further comprising: less than 0.1 atom % Na and less than 0.1 atom % K as measured by X-ray photoelectron spectroscopy.

Assignees

• Tda Research Inc

Inventors

• Srinivas Girish
• Dietz Steven

Classifications

• B01D15/00

  Separating processes involving the treatment of liquids with solid sorbents; Apparatus therefor · CPC title

• B01J20/305

  Addition of material, later completely removed, e.g. as result of heat treatment, leaching or washing, e.g. for forming pores · CPC title

• B01J2220/4825

  Polysaccharides or cellulose materials, e.g. starch, chitin, sawdust, wood, straw, cotton · CPC title

• B01J20/28069

  Pore volume, e.g. total pore volume, mesopore volume, micropore volume · CPC title

• B01J20/3078

  Thermal treatment, e.g. calcining or pyrolizing · CPC title