US 12583757 B1Patent grantUnited States

Waste-Derived Calcium Ferrite Material

Official patent title

Ca2Fe2O5/CaFe2O4/Fe2O3 nanocomposite and method of preparation thereof

Arabic title: مركب نانوي Ca2Fe2O5/CaFe2O4/Fe2O3 وطريقة تحضيره

Invention

Problem

Many waste streams remain underused, while conventional routes to integrated calcium-ferrite and iron-oxide materials can be complex, costly, and difficult to control at small particle sizes.

Why it matters

Converting eggshell and tuna-can waste into a defined multiphase material could support circular-material research, but environmental benefit depends on acid use, emissions, energy, yield, and feedstock consistency.

Approach

The method dissolves eggshell and tuna-can waste separately in concentrated HNO3, combines the calcium and iron solutions with dextrose monohydrate, heats the mixture, and calcines the resulting solid to form Ca2Fe2O5/CaFe2O4/Fe2O3.

Who may benefit

Potential beneficiaries include waste-valorization researchers, ferrite-material laboratories, ceramic and catalyst developers, recycling-process engineers, and specialty inorganic-material producers.

Potential value

The disclosure offers a combustion-based route from two waste-derived precursors to three identified crystalline phases with specified grain, particle, crystallite, and elemental ranges.

Background

Eggshell and metal-can waste can supply calcium- and iron-bearing precursors, yet mixed waste composition and contamination can complicate reproducible material synthesis. Calcium ferrites and hematite have established research interest, but integrating several phases while controlling morphology may require demanding processing. The publication proposes a combustion route using waste, concentrated nitric acid, dextrose, heating, and calcination. It reports structural and elemental characterization, but no catalytic, adsorption, electrochemical, mechanical, or other functional performance, and it does not quantify recovery yield, acid demand, emissions, waste generation, or life-cycle benefit.

Technology overview

The product contains orthorhombic Ca2Fe2O5, orthorhombic CaFe2O4, and rhombohedral Fe2O3. Granular structures average 200–400 nm and comprise aggregated spherical particles averaging 40–80 nm; crystallite size is 40–80 nm. Stated elemental ranges are 35–65 at. % oxygen, 25–45 at. % iron, and 5–25 at. % calcium. Eggshell and tuna-can solutions are each 100–300 g/L, dextrose is 50–150 g/L, stirring occurs at 150 °C, and calcination is 600–800 °C for 1–5 hours.

Potential applications

Waste-derived calcium-ferrite material research.
Multiphase ferrite structure and morphology studies.
Candidate catalyst or adsorbent screening after functional testing.
Circular-process development for mineral and metal waste streams.

Evidence-supported advantages

Three identified crystalline phases are integrated.
Eggshell and tuna-can waste are used as precursor sources.
Grain, particle, crystallite, and elemental ranges are specified.
A defined solution-combustion and calcination sequence is disclosed.

Development stage

Laboratory synthesis and XRD, SEM, HRTEM, and EDX characterization are described; functional application testing, process mass balance, scale-up, environmental assessment, and commercialization were not established.

Commercial opportunity

The route may interest waste-valorization and specialty-ferrite developers, but no market-ready function is demonstrated. Independent work must establish feedstock specifications, impurity tolerance, yield, batch consistency, acid recovery, nitrate and gas controls, calcination energy, worker safety, application performance, scale-up economics, and a comparative life-cycle assessment before sustainability or commercial value can be claimed.

Patent classifications

WIPO IPC

C01G49/06Compounds containing metals not covered by subclasses C01D or C01F
B82Y30/00Specific uses or applications of nanostructures; measurement or analysis of nanostructures; manufacture or treatment of nanostructures

CPC

C01G49/06Compounds containing metals not covered by subclasses C01D or C01F
B82Y30/00Specific uses or applications of nanostructures; measurement or analysis of nanostructures; manufacture or treatment of nanostructures
C01G49/08Compounds containing metals not covered by subclasses C01D or C01F
C01P2002/74Indexing scheme for structural and physical aspects of solid inorganic compounds
C01P2002/76Indexing scheme for structural and physical aspects of solid inorganic compounds
C01P2002/85Indexing scheme for structural and physical aspects of solid inorganic compounds
C01P2004/03Indexing scheme for structural and physical aspects of solid inorganic compounds
C01P2004/04Indexing scheme for structural and physical aspects of solid inorganic compounds
C01P2004/32Indexing scheme for structural and physical aspects of solid inorganic compounds
C01P2004/45Indexing scheme for structural and physical aspects of solid inorganic compounds
C01P2004/64Indexing scheme for structural and physical aspects of solid inorganic compounds
C01P2004/82Indexing scheme for structural and physical aspects of solid inorganic compounds

Inventors

First inventorEhab Abdelhamed Abdelrahman Ahmed
InventorBabiker Yagoub Elhadi Abdulkhair

Keywords

dicalcium ferrite
calcium ferrite
iron oxide
eggshell waste
tuna-can waste
combustion synthesis
calcination
waste valorization

Patent document and drawings

The patent publication is mapped to this record. Patent drawings remain within that publication; no separately cleared public media package has been supplied.