Millennium Carbon is a manufacturer of premium Activated Carbon from macadamia nutshell feedstock. Millennium Carbon has a proprietary two-stage process based on pyrolysis and steam activation. The central element of Millennium Carbon's technology is pyrolysis, a thermal process by which hydrocarbon materials are depolymerized in an oxygen-free environment. 

Millennium Carbon receives the macadamia nutshells, screens the feedstock to eliminate unwanted debris, and crushes the shells to increase surface area. Our specially-designed pyrolysis char reactor carbonizes the macadamia nutshells by heating the feedstock to approximately 700C in an inert atmosphere. The pyrolysis process breaks the chemical bonds within the macadamia nutshells liberating a stream of pure carbon char material and a high temperature hydrocarbon gas. The hydrocarbon gas is then cooled and filtered into usable energy in the form of condensed oil and non-condensed gases. These energy streams produce power onsite to operate the facility through a 2-Megawatt steam turbine.

As a second stage of the production process, the char moves through a rotary activation kiln in which the char is heated in the absence of oxygen, and carbon is activated through a controlled mixing of the material with superheated steam. The chemical reaction between the carbon and steam creates a highly porous carbon structure by removing carbon and impurities from lattice structure of the carbon material.

As a final step, the activated carbon is acid washed and pulverized to meet to meet the specifications for high-quality powdered activated carbon for our customers.

Our existing plant and primary technology research and development center is located near the port of Kawaihae on Hawaii Island. The plant is fully permitted and the first of its kind in the United States. The plant sits on a total of 13 acres of land and is designed to process approximately 12,000 tons of macadamia nutshells annually into our premium Activated Carbon.
"The Hawaii Island Economic Development Board is pleased to welcome Millennium Carbon to our community. The company’s innovative production process creates value from the waste stream of macadamia nutshells produced in Hawaii in an environmentally-friendly way. Millennium Carbon is working with government and private sector organizations to create new jobs and opportunities for Hawaii residents. We are glad to have Millennium Carbon in Kawaihae, Hawaii."  

- Jacqui Hoover - Executive Director - Hawaii Island Economic Development Board