Many people use the terms biochar, charcoal, and activated carbon interchangeably. There are similarities and differences.
Unlike charcoal or activated carbon, biochar is specifically designed as a soil amendment and a soil spray for crops. The shared origins of the feedstock and heating process (pyrolysis) make these products seem the same. There are key differences.
Key Points
- All three, biochar, charcoal, and activated carbon, are produced through pyrolysis (heating organic matter without oxygen)
- They share traits such as porosity, carbon-rich, lightweight, and adsorption capacity
- But they are different in purpose
- Biochar for soil health
- Charcoal for fuel and cookingÂ
- Activated carbon for filtration and remediation
- Common misconceptions are that charcoal briquettes are the same as biochar and that activated carbon is a good soil amendment. These are wrong.
- Biochar matters most in agriculture; it is tested for purity and safety and supports regenerative farming and climate resilience.
Definitions & Core Differences of Biochar, Charcoal, and Activated Carbon
The process of pyrolysis is used for the production of all three materials. That type of process requires heating organic materials in the absence of oxygen. When oxygen is present, you get ash.Â
The Definition of BiocharÂ
It is a carbon-rich solid created by heating biomass (wood, crop residues, manure, or any organic materials) in the absence of oxygen (pyrolysis). Biochar is specifically designed for soil improvement. It enhances water retention, nutrient availability, and provides habitat for beneficial microbes, among other functions.
When you incorporate biochar (enriched) into your soil, 3 major benefits are immediate:
- Improved soil structure and fertility
- Immediate sequestering of carbon and carbon credits, if applicable
- Reduced nutrient leaching and increased crop resilienceÂ
The major difference between biochar and other carbon solids is that it is produced specifically for agricultural use. Not all biochars are the same, and the characteristics of each type, along with the soil type and the agricultural purpose, determine its effectiveness.
Biochar alone is not a fertilizer, but the structure on which soil aggregation and microbial life depend. A great deal of research has been done on the characteristics of biochar from different feedstocks.
All biochars are different and that is an important point to keep in mind when determining what biochar is right for your soil and crops.
The Definition of CharcoalÂ
Like biochar, it is a carbon-rich solid produced by pyrolysis of wood or other biomass and designed for use as a fuel source. It is how you grill if you are using charcoal briquettes. It is also an energy source for major industry.
It burns hotter and cleaner than raw wood. And burning charcoal releases CO2 back into the atmosphere.
It differs considerably from biochar because it often contains additives such as binders or igniters to make your grilling experience more pleasurable.
These are the very qualities that make it harmful to add to your garden.
Charcoal doesn’t have the optimized porosity and purity of biochar. At American Biochar Company, we use the standards established by the International Biochar Initiative, so our customers know they are getting a clean and valuable soil amendment.
The Definition of Activated Carbon
Activated carbon is usually derived from charcoal or other wood feedstocks. It is processed to increase surface area and porosity dramatically.
This biosolid goes through an extra step that is either physical or chemical and is energy intensive. Â
Activated carbon is used for filtration and remediation because it adsorbs contaminants from the air, water, and many industrial processes.
The extra heating or chemical processing increases the surface area to 500-1500 m2/g vs biochar’s 10-400m2/g.Â
But there are considerable energy and environmental costs. Activation of carbon can account for up to 50% of the total energy footprint of conversion from raw biomass.Â
Activated carbon has value as an industrial product and isn’t a soil amendment.
Biochar doesn’t need this extra step activation; its porous structure is already beneficial for microbes and water retention. It does need enrichment with nutrients or microbial inoculation before adding to your soil.
Our NAKED Char is wood biochar without the addition of microbial populations or nutrients. It is a valuable addition to your compost pile, manure, or other decaying organic matter.
The Production Process of Biochar, Charcoal, and Activated Carbon
The underlying process is quite similar. There are technical differences in intensity of heat, optimal type of feedstock, and preparation for end-use.
All three products are made with heat in the absence of oxygen.Â
Each is optimized for different end-uses. And that’s what is critical to understand about biochar, charcoal, and activated carbon.
At American BioChar Company, our biochar feedstock is sustainably harvested Southern Yellow Pine. It is pyrolyzed at a temperature to optimize the pore structure for the best porosity in the soil. Â
Biochar for agricultural purposes has to be charged, or inoculated with nutrients and microbes, to jumpstart soil health.
Enriching biochar makes nutrients immediately available for plants to thrive. Through years of experimentation, we’ve found that freshwater-sourced humates offer the most consistent nutrients for plants.Â
Biochar can also be enriched with manure, compost, worm tea, or any other decaying organic materials. A consistent enriching material ensures a repeatable and reliable soil amendment.
We don’t like surprises in our product. Do you?
Applications & Benefits of Biochar, Charcoal, or Activated Carbon
This is where the three products diverge dramatically.
Biochar and Soil Fertility
Biochar is the only carbon-based product that benefits the soil and crops. Application rates vary widely depending on the biochar characteristics and the soil type. You can use too much biochar, and it has to be inoculated or conditioned before adding to your fields or garden beds.Â
Enriched biochar, in granular form, is easy to use as a top dressing or in-row fertilizer. Whatever you use to enrich the biochar will be available to plants. You can add both organic and synthetic fertilizers to the biochar.Â
Liquid biochar is also available from some suppliers. At American BioChar Company, we have found liquifying our granular biochar to 5 microns is the perfect size to remain in suspension. It can be used with common spray equipment without clogging.Â
Charcoal for Your Grill
Although historically the word "charcoal" has been used to refer to the charcoal-like substance used as a soil amendment, the two terms should not be used interchangeably.Â
In today’s world, charcoal is used for heating and cooking.
To make it effective, it’s produced with additives, binders, and accelerants. These substances are toxic to plants and can ruin your soil.Â
For example, charcoal briquettes are made from charcoal dust mixed with binders, fillers, and additives. These substances make charcoal convenient for cooking but unsuitable for soil use.
Do you want to add unknown amounts of starch, clay, limestone, borax, sodium nitrate, or lighter fluid residues to your soil?
Most of these substances are naturally occurring (not lighter fluid residue), but that doesn’t make them good for your soil.
These briquettes burn evenly, and they’re cheap. Engineered for combustion, not soil health.
They disrupt soil microbial life, alter soil chemistry, and block nutrient cycling.Â
Activated Carbon for Water and Air Filtration Systems
Activated carbon undergoes a secondary process, either using high heat and steam or chemically treating with strong acids or bases. Both activation processes leave a large footprint on the environment.
The most common feedstocks for activated carbon are coconut shells, wood, and coal. Each feedstock gives the resulting activated carbon a different pore structure, which is used for different end uses.
Air and water filtration systems often use coconut shells for the microporous activated carbon.
Wood is often used as the feedstock for use in the food and beverage industry to remove color and for gas adsorption.
Historically, coal has been the dominant feedstock, but it is less sustainable than biomass sources.Â
The second step in making activated carbon requires either chemical or high-heat treatment.
The chemicals used are phosphoric acid, potassium hydroxide, zinc chloride, and similar agents. These are effective but result in toxic wastewater, chemical residues, and environmental burdens that have to be carefully monitored.
In the United States, the preferred method to produce activated carbon is with the physical process of high heat.
This is energy-intensive, but it has a lower impact on the environment. Biochar or carbonized material is reheated to 800-100 °C (1472-1832°F) in the presence of steam or CO2.Â
The advantages of this method are no chemical residues or toxic wastewater, easier compliance with US environmental regulations, and it produces a high-quality, consistent product for water and air filtration.
Common practice is to treat pollution issues in situ, and once the pollutants are adsorbed, the activated carbon acts as a long-term immobilizer. It is often paired with microbial or chemical amendments to degrade the contaminants.
The only time you’d use activated carbon on your soil is if you have a serious pollutant issue that needs immediate remediation.
Common Misconceptions Of Biochar, Charcoal, and Activated Carbon
To be blunt, you can’t grind up charcoal briquettes to make biochar or any kind of suitable soil amendment.
That charcoal dust bound into that briquette has little pore structure and lots of substances that are harmful to your soil.
Activated carbon could be used as a soil amendment, but it would never be cost-effective. It takes a lot of energy to produce and is suitable for high-tech uses.
The soil microbial populations are disturbed when activated carbon is injected into the soil. The pH is often changed, and because it’s so porous, it ties up nutrients necessary for plant growth, resulting in crop failures.
In contrast, most biochars have a porous structure that is beneficial for microbes and water retention. The feedstock determines the size (in microns) of the pores.
Our Southern Yellow Pine biochar has the perfect pore size for microbial and soil health. We carefully enrich our biochar with freshwater-sourced humates.
Lab tests over many years have proven that using a consistent product such as ACTIV12 AG from Black Earth ensures a repeatable and standardized soil amendment.
Our BioChar Commitment to Soil Health Regeneration
Almost all soils that are used for crops, lawns, or gardens suffer from some degree of degradation.
Our premium, lab and field-tested biochar products are tailored specifically for agricultural use.
We have helped specialty crop growers, arborists, orchardists, and turf professionals overcome obstacles to greater profits.Â
We have the data to prove how our biochar blends, VITAL Blend granular and VITAL Blend 5M liquid, have dramatically increased both yield and quality of our growers’ crops. Â
In one field study with blueberries, with only one application of our VITAL Blend 5M the antioxidants increased 11%, sugar 3.1%, and protein a whopping 125%.Â
We are committed to regenerative solutions that create ecological and financial returns. You can heal your land and increase your profit margins at the same time.
Biochar is Uniquely Positioned for Agriculture
Charcoal and activated carbon have their place. But it’s not in agriculture. Enriched biochar is the future of soil health.Â
Biochar builds soil health, helps with water retention, and creates the structure to house beneficial microbial populations. Nutrient cycling is enabled by microbes, which results in improved plant health.Â
As we experience more extreme weather events, more drought, more floods, more heat, it’s good to know beneficial microbes are safe in the soil beneath our feet.
Regenerative agricultural practices such as cover crops, no-till, and livestock integration are supported with additional fixed carbon in the soil.
Biochar supplies fixed carbon, and the enriching agents supply the active carbon for an immediate boost in microbial health.
When we have healthy soil, we have plants that are less susceptible to pest and disease issues. They also have nutrient levels that make them more nutritious for us (and other plant eaters).
As you plan your 2026 cropping season, consider adding biochar to your input regime. It makes the input use more effective and retains nutrients in the plant root zone.
Contact us to find out how to make biochar a part of your future.
