Activated carbon spheres cleaning polluted air.

Breathe Easier: How These Tiny Carbon Spheres Could Solve Mercury Pollution

Theo Raines in Climate & Environment August 2025 • 3 min read.

"Innovative Material Promises a Breath of Fresh Air in the Fight Against Toxic Mercury Emissions"

For decades, coal has powered industries and economies, particularly in rapidly developing nations. Yet, this energy source comes at a significant environmental cost. The burning of coal releases harmful pollutants into the atmosphere, including sulfur dioxide (SO2), nitrogen oxides (NOx), and heavy metals like mercury (Hg), arsenic (As), and lead (Pb). These pollutants pose severe risks to human health and contribute to various environmental disasters.

Mercury, in particular, is a highly toxic element that can accumulate in the environment and living organisms. It exists in various forms, with elemental mercury (Hg0) being especially challenging to capture due to its volatility and low solubility. Traditional methods often struggle to efficiently remove this form of mercury from industrial emissions.

But what if there was a more effective way to trap this elusive pollutant? Recent research has focused on advanced materials capable of adsorbing and converting mercury into less harmful forms. One promising solution involves the use of activated carbon spheres modified with cerium oxide (CeO2). These tiny spheres possess unique properties that could revolutionize mercury removal technologies.

The Science Behind the Spheres: How They Work

Activated carbon spheres cleaning polluted air.

Researchers have successfully created activated carbon spheres with well-dispersed CeO2 particles through a process involving grafting and coordinating reactions. These spheres are designed to maximize surface area and enhance their ability to capture mercury. The process begins with resin-based activated carbon spheres, which are then modified using methyl methacrylate (MMA) and cerium(III) nitrate salt. Steam activation further refines the material, creating a highly porous structure ideal for adsorption.

The key to the effectiveness of these spheres lies in the synergistic interaction between the activated carbon and the CeO2 particles. The carbon provides a large surface area for mercury to adhere to, while the CeO2 acts as a catalyst, promoting the oxidation of elemental mercury into mercuric oxide (HgO), a more stable and easily captured form.

The study highlights several critical factors that influence the performance of these modified spheres:

Optimal Cerium(III) Nitrate Loading: A 7% loading of cerium(III) nitrate yields the best results.
Reaction Temperature: A temperature of 150°C provides the ideal conditions for mercury removal.
Oxygen Content: A 5% oxygen content in the gas stream enhances the oxidation process.

The presence of other gases can also impact the spheres' performance. Sulfur dioxide (SO2) can inhibit mercury removal in the absence of oxygen but can facilitate it when oxygen is present. Nitrogen monoxide (NO) generally promotes mercury removal, while water vapor tends to inhibit the process.

The Future of Mercury Removal

These findings represent a significant step forward in the fight against mercury pollution. The CeO2-modified activated carbon spheres offer a promising, cost-effective, and sustainable solution for capturing and removing elemental mercury from industrial emissions. With further research and development, this technology could play a crucial role in protecting human health and the environment from the harmful effects of mercury.

About this Article -

This article was crafted using a human-AI hybrid and collaborative approach. AI assisted our team with initial drafting, research insights, identifying key questions, and image generation. Our human editors guided topic selection, defined the angle, structured the content, ensured factual accuracy and relevance, refined the tone, and conducted thorough editing to deliver helpful, high-quality information.See our About page for more information.

This article is based on research published under:

DOI-LINK: 10.1007/s10853-018-3019-4, Alternate LINK

Title: Synthesis Of Ceo2-Modified Activated Carbon Spheres By Grafting And Coordinating Reactions For Elemental Mercury Removal

Subject: Mechanical Engineering

Journal: Journal of Materials Science

Publisher: Springer Science and Business Media LLC

Authors: Changming Zhang, Wen Song, Xiaochao Zhang, Rui Li, Songjian Zhao, Caimei Fan

Published: 2018-10-19

Everything You Need To Know

How do the modified activated carbon spheres capture and remove elemental mercury (Hg0) more effectively than traditional methods?

The innovative approach employs activated carbon spheres modified with cerium oxide (CeO2). These spheres are designed to adsorb and convert elemental mercury (Hg0) into mercuric oxide (HgO). The activated carbon provides a large surface area, and the cerium oxide acts as a catalyst to oxidize the elemental mercury, making it easier to capture. This contrasts with traditional methods that often struggle with the volatility of elemental mercury.

What is the process for creating these activated carbon spheres modified with cerium oxide (CeO2), and how does it enhance their mercury capture capabilities?

The activated carbon spheres are created using resin-based activated carbon spheres modified with methyl methacrylate (MMA) and cerium(III) nitrate salt. Steam activation refines the material to create a highly porous structure, maximizing the surface area for mercury adsorption. The cerium oxide (CeO2) is introduced through grafting and coordinating reactions to ensure it is well-dispersed within the carbon structure.

What are the key factors that influence the effectiveness of cerium oxide (CeO2)-modified activated carbon spheres in removing mercury?

Several factors influence the efficiency of mercury removal using cerium oxide (CeO2)-modified activated carbon spheres. An optimal loading of 7% cerium(III) nitrate yields the best results. A reaction temperature of 150°C provides ideal conditions. A 5% oxygen content in the gas stream enhances the oxidation process of elemental mercury (Hg0). Other gases like sulfur dioxide (SO2), nitrogen monoxide (NO), and water vapor can also affect the spheres' performance, either promoting or inhibiting mercury removal.

How do other pollutants, such as sulfur dioxide (SO2) and nitrogen monoxide (NO), affect the performance of the cerium oxide (CeO2)-modified activated carbon spheres in capturing mercury?

While the cerium oxide (CeO2)-modified activated carbon spheres show promise in capturing elemental mercury (Hg0), their interaction with other pollutants is complex. Sulfur dioxide (SO2) can inhibit mercury removal without oxygen but facilitate it with oxygen. Nitrogen monoxide (NO) generally promotes mercury removal, while water vapor tends to inhibit it. Further research should explore these interactions and their impact on the overall performance and longevity of the spheres in real-world industrial settings.

What are the potential long-term implications of using cerium oxide (CeO2)-modified activated carbon spheres for mercury removal, and why is this technology considered a significant advancement?

The cerium oxide (CeO2)-modified activated carbon spheres represent a significant advancement because they offer a cost-effective and sustainable solution for capturing and removing elemental mercury (Hg0) from industrial emissions. This can greatly contribute to reducing mercury pollution and protecting human health and the environment. While this technology shows promise, further research is needed to optimize its performance under various conditions and assess its long-term effectiveness in real-world scenarios.