Particulate sorption medium prepared from partially decomposed organic matter

Patent metadata

Field	Value
Publication number	US-10118154-B2
Application number	US-201615289342-A
Country	US
Kind code	B2
Filing date	Oct 10, 2016
Priority date	Mar 15, 2013
Publication date	Nov 6, 2018
Grant date	Nov 6, 2018

Abstract

A process for the preparation from a partially decomposed organic material like peat a granulated or pelletized sorption medium using low-temperature, thermal activation of the sorption medium to produce a high degree of granule or pellet hardness balanced against an efficacious level of ion-exchange and adsorption capacity, followed by chemical treatment of the thermally-activated sorption material via an acid solution and a salt solution to increase its ion-exchange and adsorption performance while minimizing the transfer of natural impurities found in the sorption medium to an aqueous solution is provided by this invention. The sorption medium of this invention can be used in a variety of aqueous solution treatment processes, such as wastewater treatment.

First claim

We claim:

1. A process for the production from partially decomposed organic matter of a sorption media for use in the treatment of aqueous solutions comprising at least one major toxic metal and at least one more-innocuous metal to remove at least one type of aqueous contaminant therein, comprising the steps of:
(a) supplying an amount of the partially decomposed organic matter to a granulating machine;
(b) granulating the partially decomposed organic matter;
(c) drying the granules;
(d) thermally activating the granules without chemical activation using an activation heat medium at a temperature of about 175-287° C., wherein the granule has a Ball-Pan Hardness number of about 75%-100% and is suitable for sorption of the aqueous contaminant found in the aqueous solution; and
(e) chemically treating the thermally-activated granule with a salt solution without treatment with an acid, wherein the salt solution is preselected in the form of a soluble salt compound having a cation constituent and an anion constituent, wherein:
(i) the cation constituent of the salt solution is selected from the group consisting of any 1 + or 2 + cation of, without limitation, ammonium (NH 4 + ), ammonium groups (NR 4 + ), sodium, potassium, lithium, cesium, beryllium, magnesium, calcium, barium, manganese, copper, zinc, strontium, iron, and lead;
(ii) the anion constituent of the salt solution is selected from the group consisting of SO 4 2− , SO 3 2− , NO 3 − , NO 2 − , PO 4 2− , Cl − , I − , Br − , F − , HCOO − , CH 3 COO − , C 2 H 5 COO − , C 3 H 7 COO − , C 4 H 9 COO − , and ClO 4 ;
(iii) the chemical treatment of the granule with the salt solution places the selected cations provided by the cation constituent of the salt solution onto the active adsorption sites in the granule;

(f) wherein the presence of the cations of the cation constituent of the salt solution on the active sites of the granule alters the coefficient that defines the solution equilibrium to influence the adsorption capacity of the thermally-activated and chemically-treated sorption medium granules more in favor of the major toxic metal adsorption by the sorption medium granules at the expense of the more-innocuous metal contaminant adsorption, so that the granules can sorb the major toxic metal contaminants from the treated aqueous solution, while leaving a substantial portion of the more-innocuous metal contaminants in the aqueous solution.

2. The process of claim 1 , wherein the cation of the cation constituent of the soluble salt compound is selected to match the cations of the more-innocuous metal contaminant.

3. The process of claim 1 , wherein the pre-selected soluble salt compound for the salt solution used in the chemical treatment step for the production of the sorption medium results in an improved breakthrough capacity for the major toxic metal contaminant up to 16.43 mg/g at 50 ppb of the major toxic metal.

4. The process of claim 1 , wherein the major toxic metal contaminant found in the aqueous solution is selected from the group consisting of a chemical element or compound that poses a health risk to humans or animals, or is otherwise subject to environmental laws or regulations in the form of heavy metals like comprising arsenic, lead, mercury, cadmium, manganese, iron, zinc, nickel, copper, molybdenum, cobalt, nickel, chromium, palladium, stannum, or aluminum; radioactive materials like cesium or various isotopes of uranium; sulfates, phosphorous, selenium, boron, ammonia, refrigerants, and radon gases.

5. The process of claim 1 , wherein the more-innocuous metal contaminant found in the aqueous solution is selected from the group consisting of a chemical element or compound found in an aqueous solution that does not necessarily pose a health risk to humans or animals or is otherwise subject to environmental laws or regulations in the form of metals comprising magnesium, beryllium, strontium, barium, calcium, manganese, copper, zinc, iron, lead, potassium, lithium, ammonium, and ammonium groups.

6. The process of claim 1 further comprising treatment of the thermally-activated granule with an acid solution to dissolve out a constituent part of the granule.

7. A process for the production from partially decomposed organic matter of a sorption media for use in the treatment of aqueous solutions comprising at least one major toxic metal and at least one more-innocuous metal to remove at least one type of aqueous contaminant therein, comprising the steps of:
(a) supplying an amount of a thermally-activated, granulated, partially decomposed organic matter that was not chemically activated;
(b) chemically treating the thermally-activated granule with a salt solution without treatment with an acid, wherein the salt solution is preselected in the form of a soluble salt compound having a cation constituent and an anion constituent, wherein:
(i) the cation constituent of the salt solution is selected from the group consisting of any 1 + or 2 + cation of, without limitation, ammonium (NH 4 + ), ammonium groups (NR 4 + ), sodium, potassium, lithium, cesium, beryllium, magnesium, calcium, barium, manganese, copper, zinc, strontium, iron, and lead;
(ii) the anion constituent of the salt solution is selected from the group consisting of SO 4 2− , SO 3 2− , NO 3 − , NO 2 − , Po 4 2− , Cl − , I − , Br − , F − , HCOO − , CH 3 COO − , C 2 H 5 COO − , C 3 H 7 COO − , C 4 H 9 COO − , and ClO 4 − ;
(iii) the chemical treatment of the granule with the salt solution places the selected cations provided by the cation constituent of the salt solution onto the active adsorption sites in the granule;

(c) wherein the presence of the cations of the cation constituent of the salt solution on the active sites of the granule alters the coefficient that defines the solution equilibrium to influence the adsorption capacity of the thermally-activated and chemically-treated sorption medium granules more in favor of the major toxic metal adsorption by the sorption medium granules at the expense of the more-innocuous metal contaminant adsorption, so that the granules can sorb the major toxic metal contaminants from the treated aqueous solution, while leaving a substantial portion of the more-innocuous metal contaminants in the aqueous solution.

8. The process of claim 7 , wherein the cation of the cation constituent of the soluble salt compound is selected to match the cations of the more-innocuous metal contaminant.

9. The process of claim 7 , wherein the pre-selected soluble salt compound for the salt solution used in the chemical treatment step for the production of the sorption medium results in an improved breakthrough capacity for the major toxic metal contaminant up to 16.43 mg/g at 50 ppb of the major toxic metal.

10. The process of claim 7 , wherein the major toxic metal contaminant found in the aqueous solution is selected from the group consisting of a chemical element or compound that poses a health risk to humans or animals, or is otherwise subject to environmental laws or regulations in the form of heavy metals like comprising arsenic, lead, mercury, cadmium, manganese, iron, zinc, nickel, copper, molybdenum, cobalt, nickel, chromium, palladium, stannum, or aluminum; radioactive materials like cesium or various isotopes of uranium; sulfates, phosphorous, selenium, boron, ammonia, refrigerants, and radon gases.

11. The process of claim 7 , wherein the more-innocuous metal contaminant found in the aqueous solution is selected from the group consisting of a chemical element or compound found in an aqueous solution that does not necessarily pose a health risk to humans or animals or is otherwise subject to environmental l

Assignees

• American Peat Tech Llc
• Univ Minnesota

Inventors

• Kolomitsyn Igor V
• Jones Peggy Wallgren
• Green Douglas A

Classifications

• B01J20/20

  comprising free carbon; comprising carbon obtained by carbonising processes · CPC title

• C02F2303/16

  Regeneration of sorbents, filters · CPC title

• C02F2101/20

  Heavy metals or heavy metal compounds · CPC title

• C02F2001/425

  using cation exchangers · CPC title

• B01J2220/4887

  Residues, wastes, e.g. garbage, municipal or industrial sludges, compost, animal manure; fly-ashes · CPC title