IP Library Granted Patent US 12,397,277
Granted Patent B2
US 12,397,277 · App. 17/458,213 · Granted Aug 26, 2025

Method for directly reducing a material by means of microwave radiation

Inventors: José Manuel Serra Alfaro (Valencia, ES); José Manuel Catala Civera (Valencia, ES); Beatriz García Baños (Valencia, ES); Juan Francisco Borrás Morell (Valencia, ES); Laura Navarrete Algaba (Valencia, ES)
Assignees: Universitat Politècnica de València; Consejo Superior de Investigaciones Científicas
B01J19/126C01B3/061C01B32/40H05B6/806B01J2219/1206
View Patent ↗
Loading inventors, assignments & file history…
Monitor This Case
Get email alerts when status or documents change.
Order Certified Copies
Most orders are placed with the USPTO same day — all within 24 business hours.
Order via The Patent Place →
Pre-filled with this patent's details
Quick Facts
Patent No.
US 12,397,277
App. No.
17/458,213
Granted
Aug 26, 2025
Kind
B2
Abstract

The present invention relates to the reduction of materials at low temperatures (<600° C.) by means of microwave radiation without needing to use chemical reducing agents or electrical contacts. It relates more specifically to a method for reducing a material, which comprises the following steps: applying microwave radiation to a material disposed in a microwave application cavity; and separating simultaneously the fluid oxidation products generated from the reduced material, such that the method is carried out without chemical reducing agents or electrical contacts.

Claims (39)

1. A process for the direct chemical reduction of a material, comprising the following steps:

applying microwave radiation to a material placed in a microwave applicator cavity,

heating to at least exceeding a shot temperature in the material, and

separating fluid oxidation products generated from the reduced material,

such that the process is carried out without using reducing chemical agents,

wherein:

the material is an inorganic material,

application of microwave radiation produces a temperature increase between 50-200° C. over the shot temperature, and

the shot temperature is a temperature at which electrical conductivity of the material is increased at least 4% within a 4° C. temperature increase with respect to the electrical conductivity of the material without reduction.

2. The process according to claim 1 , wherein the process is carried out without use of electrical contacts.

3. The process according to claim 1 wherein the steps are carried out in a container that has the ability to evacuate fluids.

4. The process according to claim 1 wherein the step of applying microwave radiation produces a temperature increase between 50-100° C.

5. The process according to claim 1 , wherein the material that is reduced is in one of a solid state, a melted state, a suspension in a liquid, or a solution in a liquid.

6. The process according to claim 5 , wherein the liquid is water or a hydrocarbon able to be in a liquid state at the conditions at which the process takes place.

7. The process according to claim 1 , wherein the separation of the fluid oxidation products generated from the reduced material is carried out by means of one of:

the application of vacuum,

the use of an entrainment fluid,

use of a reactive fluid that consumes the reduced material,

use of a selective separator of the generated oxidation product, or

a combination thereof.

8. The process according to claim 1 , further comprising a step of in-situ measurement of the conductivity of the material to be reduced by applying microwave radiation from a second source and an associated receiver without mutual inference.

9. The process according to claim 1 , wherein the material is a solid material, the composition of which comprises cerium oxide doped with gadolinium (CGO).

10. The process according to claim 1 , that further comprises the following steps:

placing the material in a container capable of evacuating fluids and inert to microwave radiation,

inserting the container through an orifice located in a wall of the applicator cavity in an area of uniform and an electric field as intense as possible for uniform and efficient heating,

identifying the “shot temperature” for that material,

carrying out, while the microwave radiation is applied, a continuous adjustment of the power applied for the radiation, and

separating the fluid oxidation products generated from the reduced material, wherein the process is carried out without the use of reducing chemical agents.

11. The process of claim 1 further comprising the steps of:

contacting the reduced material with a gaseous stream, and

selectively absorbing one or more components of the gaseous stream.

12. The process of claim 1 further comprising the steps of:

contacting the reduced material with a gaseous stream, and

selectively removing at least one of O 2 , F 2 , Cl 2 , Br 2 , HCl, HBr, HF, H 2 S or mixtures thereof from the gaseous stream.

13. The process of claim 1 further comprising the step of:

carrying out a reaction of the material in a reduced state and a second organic molecule which can be reduced.

14. The process of claim 1 further comprising:

generating a chemical product through the reaction of the material in a reduced state and a molecule selected from alkanes, alkenes, naphthenes and aromatic hydrocarbons.

15. The process of claim 1 further comprising the step of recharging batteries with the reduced material.

Assignments (1)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Oct 6, 2021
From: SERRA ALFARO, JOSÉ MANUEL; CATALA CIVERA, JOSÉ MANUEL; GARCÍA BAÑOS, BEATRIZ; BORRÁS MORELL, JUAN FRANCISCO; NAVARRETE ALGABA, LAURA
To: UNIVERSITAT POLITÈCNICA DE VALÈNCIA; CONSEJO SUPERIOR DE INVESTIGACIONES CIENTÍFICAS
Reel/Frame 057713/0912 →
Priority Claims (1)
ES ES201930189 · Feb 28, 2019 · national
Continuity (2)
Continuation PCTES2020070146 · Feb 28, 2020
Related Publication 20220016595A1 · Jan 20, 2022
References Cited (18)
US 5507927A · Emery · 1996 [cited by applicant]
US 6437303B1 · Dorr · 2002 [cited by examiner]
US 20040100280A1 · Ju et al. · 2004 [cited by applicant]
CN 109022760A · 2018 [cited by applicant]
DE 4226496A1 · 1993 [cited by applicant]
EP 2023068A1 · 2009 [cited by applicant]
JP 2009199855A · 2009 [cited by applicant]
JP 2017204438A · 2017 [cited by applicant]
JP 2018142461A · 2018 [cited by applicant]
Catala Civera et al.; “Dynamic Measurement of Dielectric Properties of Materials at High Temperature During Microwave Heating in a Dual Mode Cylindrical Cavity”; IEEE Transactions on Microwave Theory and Techniques, vol… [cited by applicant]
Xin Wang et al.; “Thermodynamics and kinetics of carbothermal reducation of zinc ferrite by microwave heating”; ScienceDirect; www.sciencedirect.com; Trans. Nonferrous Met. Soc China 23(2013) 3808-3815—(8) pages. [cited by applicant]
International Search Report dated Jun. 8, 2020; Application No. PCT/ES2020/070146—(3) pages. [cited by applicant]
Japaneses Patent Office Action for Application No. 2021-549952 dated Mar. 26, 2024 (6 pages, including an English Summary). [cited by applicant]
Extended European Search Report dated Dec. 23, 2022; Application No. 20763309.0-1101 / 3932538 PCT/ES2020070146—(1) page. [cited by applicant]
Saudi Arabia First Examination dated Dec. 29, 2022—(11) pages. [cited by applicant]
Written Opinion Application No. 20763309.0—(4) pages. [cited by applicant]
Translation of Final Rejection in Japanese Application No. 2021-549952, dated Sep. 3, 2024 (2 pages). [cited by applicant]
Official Action Summary from United Arab Emirates Application No. P6001511/2021, dated Feb. 15, 2024 (8 pages). [cited by applicant]