	US 12,304,891 B2
	Removal of Al-salts, HCl, NaCl and organic by-product from DIOPAT suspension by means of ceramic membranes in strong acidic conditions at high temperature
Jacek Malisz, Ludwigshafen am Rhein (DE); Andreas Mueller, Ludwigshafen am Rhein (DE); Johannes Nagel, Ludwigshafen am Rhein (DE); and Dominik Lanzinger, Ludwigshafen am Rhein (DE)
Assigned to BASF SE, Ludwigshafen am Rhein (DE)
Appl. No. 17/261,865
Filed by BASF SE, Ludwigshafen am Rhein (DE)
PCT Filed Jul. 18, 2019, PCT No. PCT/EP2019/069390 § 371(c)(1), (2) Date Jan. 20, 2021, PCT Pub. No. WO2020/016366, PCT Pub. Date Jan. 23, 2020.
Claims priority of application No. 18184692 (EP), filed on Jul. 20, 2018.
Prior Publication US 2021/0292286 A1, Sep. 23, 2021
This patent is subject to a terminal disclaimer.
Int. Cl. C07D 251/24 (2006.01); B01D 69/02 (2006.01); B01D 71/02 (2006.01); C02F 9/00 (2023.01); C02F 1/02 (2023.01); C02F 1/44 (2023.01); C02F 1/66 (2023.01)

CPC C07D 251/24 (2013.01) [B01D 69/02 (2013.01); B01D 71/025 (2013.01); C02F 9/00 (2013.01); B01D 2325/02833 (2022.08); C02F 1/02 (2013.01); C02F 1/44 (2013.01); C02F 1/66 (2013.01)]

17 Claims

1. A process for isolating 2,4-bis-(2,4-dihydroxyphenyl)-6-(4-methoxyphenyl)-1,3,5-triazine (DIOPAT) from an aqueous alkaline mixture M comprising

(i) the 2,4-bis-(2,4-dihydroxyphenyl)-6-(4-methoxyphenyl)-1,3,5-triazine;

(ii) 2,4-dihydroxybenzophenone; and

(iii) aluminum salts;

wherein the process comprises the steps of

a) precipitating the 2,4-bis-(2,4-dihydroxyphenyl)-6-(4-methoxyphenyl)-1,3,5-triazine by acidifying the mixture M to a pH<1;

b) heating the acidified mixture M to a temperature in the range of from 80° C. to 95° C.;

c) separating the precipitated 2,4-bis-(2,4-dihydroxyphenyl)-6-(4-methoxyphenyl)-1,3,5-triazine from the dissolved 2,4-dihydroxybenzophenone and the dissolved aluminium salts with a ceramic membrane by means of diafiltration with water, whereby the pH increases from <1 to at most 3 and the temperature remains in the range of from 80° C. to 95° C.,

wherein the separation step c) provides the precipitated 2,4-bis-(2,4-dihydroxyphenyl)-6-(4-methoxyphenyl)-1,3,5-triazine in the form of an aqueous suspension in the retentate, and the dissolved 2,4-dihydroxybenzophenone and the dissolved aluminum salts in the form of an aqueous solution in the permeate.