Method for processing waste water loaded with nitrogen-containing compounds
View Patent ↗The invention relates to a method for purifying wastewater loaded with nitrogen-containing compounds, wherein the wastewater loaded with nitrogen-containing compounds is reacted with a smectic sheet silicate, wherein a clay material loaded with nitrogen-containing compounds is obtained, and the clay material loaded with nitrogen-containing compounds is separated off, wherein purified wastewater is obtained.
1. Method for purifying wastewater loaded with nitrogen-containing compounds to obtain purified wastewater, wherein the method comprises:
reacting the wastewater loaded with nitrogen-containing compounds with a smectic sheet silicate to obtain a clay material loaded with nitrogen-containing compounds, and
separating the clay material loaded with nitrogen-containing compounds from the loaded wastewater to produce a purified wastewater
wherein the nitrogen-containing compounds comprise a quaternary alkyl ammonium compound,
wherein the smectic sheet silicate has an ion exchange capacity of from 40 to 85 meq/100 g, and
wherein the smectic sheet silicate has a swelling capacity in the range of from 20 to 40 ml/2g.
2. Method according to claim 1 , wherein the quaternary alkyl ammonium compound carries alkyl groups which have a carbon count of less than 6.
3. Method according to claim 1 , wherein the level of the nitrogen-containing compounds in the wastewater loaded with nitrogen-containing compounds is less than 5000 mg/1 N.
4. Method according to claim 1 , wherein the wastewater loaded with nitrogen-containing compounds has a concentration of alkali ions of less than 15000 mg/1 X + , wherein X + is an alkali metal ion.
5. Method according to claim 1 , wherein the wastewater loaded with nitrogen-containing compounds has a concentration of Al 3+ ions of less than 15 mg/ 1 Al 3+ .
6. Method according to claim 1 , wherein the loaded wastewater has a pH of more than 10 .
7. Method according to claim 1 , wherein the method further comprises obtaining the wastewater loaded with nitrogen-containing compounds from a synthesis of a zeolite.
8. Method according to claim 1 , wherein the smectic sheet silicate comprises a neutral or an alkali-activated smectic sheet silicate.
9. Method according to claim 1 , wherein the smectic sheet silicate has a level of sodium ions extractable with ammonium ions which is between 80and 140% of the ion exchange capacity of the smectic sheet silicate.
10. Method according to claim 1 , wherein the smectic sheet silicate reacted with the wastewater loaded with nitrogen-containing compounds is added in a quantity of more than 1 g/100 ml.
11. Method according to claim 1 , wherein the smectic sheet silicate added to the wastewater loaded with nitrogen-containing compounds is in the form of a suspension.
12. Method according to claim 11 , wherein the suspension has a solids content from 2.5 to 20 wt.-%.
13. Method according to claim 1 , wherein the purified wastewater comprises less than 800 ppm nitrogen-containing compounds.
14. Method according to claim 1 , wherein the smectic sheet silicate is reacted with the wastewater loaded with nitrogen-containing compounds for less than 10 minutes.
15. Method for recovering nitrogen-containing compounds from a wastewater containing nitrogen-containing compounds comprising:
producing the clay material loaded with the nitrogen-containing compounds by carrying out the method according to claim 1 , and
recovering the nitrogen-containing compound from the clay material loaded with the nitrogen-containing compounds by a process selected from the group consisting of expelling the nitrogen-containing compound from the clay material with a solution of an alkali metal salt, eluting with an acid and using an elution gradient.