Nano-enabled activated carbon blocks to enable removal of oxyanions from water

Patent metadata

Field	Value
Publication number	US-11396004-B2
Application number	US-201916355016-A
Country	US
Kind code	B2
Filing date	Mar 15, 2019
Priority date	Mar 15, 2019
Publication date	Jul 26, 2022
Grant date	Jul 26, 2022

Abstract

A method for preparing a nano-enabled activated carbon block, a nano-enabled activated carbon block produced by the method, a household water filtration system comprising the nano-enabled activated carbon block, and a method for filtering tap water using the household water filtration system are provided. The method includes contacting a solution including a metal(lic) precursor (e.g. a titanium compound and/or an iron compound and/or a zirconium compound) with activated carbon particles such that the solution fills pores of the activated carbon particles. The method further includes causing a metal (hydr)oxide (e.g. titanium dioxide and/or zirconium dioxide and/or iron oxide) to precipitate from the solution thereby causing metal oxide nanoparticles to become deposited within pores of the activated carbon particles. The method also includes preparing a nano-enabled activated carbon block from the activated carbon particles having metal oxide nanoparticles deposited within the pores thereof.

First claim

What is claimed is:

1. A method of preparing an activated carbon block, the activated carbon block comprising activated carbon defining pores and iron hydroxide (Fe(OH) 3 ) particles disposed in the pores, said method comprising:
providing a solution comprising anhydrous iron trichloride (FeCl 3 ) and an alcohol;
providing activated carbon particles;
combining the solution and the activated carbon particles to form a slurry;
raising pH of the slurry such that Fe(OH) 3 precipitates out of the solution producing activated carbon particles comprising the activated carbon particles with Fe(OH) 3 nanoparticles deposited within the pores thereof;
rinsing the activated carbon particles with water to remove byproducts and/or impurities therefrom;
rinsing the activated carbon particles with a neutralizing agent to neutralize the activated carbon particles;
drying the activated carbon particles; and
forming the activated carbon block with the activated carbon particles.

2. The method of claim 1 , wherein the step of forming the activated carbon block with the activated carbon particles comprises:
combining the activated carbon particles with a binder to form a mass;
compressing the mass at a pressure of from about 30 psi to about 120 psi; and
heating the mass under pressure to a temperature of from about 175° C. to about 205° C. thereby producing the activated carbon block; and

further comprising:
cooling the activated carbon block;
optionally, flushing the activated carbon block with water;
optionally, wherein the activated carbon particles include a mean particle diameter in the range of about 60 to about 80 μm and a particle size distribution having less than 10 wt. % particles larger than 140 mesh and less than 10 wt. % particles smaller than 500 mesh, wherein wt. % is measured with respect to a total mass of the activated carbon;
optionally, wherein the binder comprises an ultra-high molecular weight binder, optionally the ultra-high molecular weight binder having a melt index of not more than 1 g/min as measured using ASTM D1238 at 190° C. and 15 kg load.

3. The method of claim 1 , wherein:
i) the activated carbon block comprises from about 20 wt. % to about 35 wt. % iron;
ii) optionally, the alcohol comprises methanol.

4. The method of claim 3 , wherein ii) the alcohol comprises methanol.

5. The method of claim 1 , wherein:
the activated carbon particles include a mean particle diameter in the range of about 60 to about 80 μm and a particle size distribution having less than 10 wt. % particles larger than 140 mesh and less than 10 wt. % particles smaller than 500 mesh, wherein wt. % is measured with respect to a total mass of the activated carbon; and
the binder comprises an ultra-high molecular weight binder, optionally the ultra-high molecular weight binder having a melt index of not more than 1 g/min as measured using ASTM D1238 at 190° C. and 15 kg load.

6. The method of claim 1 , wherein pH of the slurry is raised to about 12 in the step of raising pH of the slurry.

7. A method of preparing an activated carbon block, the activated carbon block comprising activated carbon defining pores and iron hydroxide (Fe(OH) 3 ) particles disposed in the pores, said method comprising:
providing an activated carbon block formed from activated carbon particles and a binder;
providing a solution comprising anhydrous iron trichloride (FeCl 3 ) and an alcohol;
contacting the activated carbon block and the solution to fill the pores with the solution;
raising pH of the solution such that Fe(OH) 3 precipitates out to form an activated carbon block comprising the activated carbon with Fe(OH) 3 nanoparticles deposited within pores thereof;
rinsing the activated carbon block with water to remove byproducts and/or impurities therefrom;
rinsing the activated carbon block with a neutralizing agent to neutralize the activated carbon block;
optionally, flushing the activated carbon block with water;
optionally, wherein the activated carbon particles include a mean particle diameter in the range of about 60 to about 80 μm and a particle size distribution having less than 10 wt. % particles larger than 140 mesh and less than 10 wt. % particles smaller than 500 mesh, wherein wt. % is measured with respect to a total mass of the activated carbon;
optionally, wherein the binder comprises an ultra-high molecular weight binder, optionally the ultra-high molecular weight binder having a melt index of not more than 1 g/min as measured using ASTM D1238 at 190° C. and 15 kg load.

8. The method of claim 7 , wherein:
i) the activated carbon block comprises from about 20 wt. % to about 35 wt. % iron;
ii) optionally, the alcohol comprises methanol.

9. The method of claim 8 , wherein ii) the alcohol comprises methanol.

10. The method of claim 7 , wherein:
the activated carbon particles include a mean particle diameter in the range of about 60 to about 80 μm and a particle size distribution having less than 10 wt. % particles larger than 140 mesh and less than 10 wt. % particles smaller than 500 mesh, wherein wt. % is measured with respect to a total mass of the activated carbon; and
the binder comprises an ultra-high molecular weight binder, optionally the ultra-high molecular weight binder having a melt index of not more than 1 g/min as measured using ASTM D1238 at 190° C. and 15 kg load.

11. The method of claim 7 , wherein pH of the slurry is raised to about 12 in the step of raising pH of the slurry.

Assignees

• Access Business Group Int Llc
• Univ Arizona State

Inventors

• Cai Zhenxiao
• Mollema Scott A
• Atkinson Ariel J
• Hristovski Kiril D
• Markovski Jasmina S
• Westerhoff Paul K

Classifications

• C02F1/288

  using composite sorbents, e.g. coated, impregnated, multi-layered · CPC title

• B01J20/20 Primary

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

• C02F2101/103

  Arsenic compounds · CPC title

• C02F2307/10

  as part of a potable water dispenser, e.g. for use in homes or offices · CPC title

• B01J20/3078

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