“Blue” calcium carbonate resulting from bivalve mollusc shells

# Record card
Thematic areas
Energy and environmental sustainability
Energy and environmental sustainability / Renewable sources
Health & Biotech
Health & Biotech / Care, Hygiene, Cosmetics
Energy and environmental sustainability / Waste management
Additive and advanced industrial manufacturing
Energy and environmental sustainability / Pollution treatment (air, soil, water)
Chemicals & Physics
Chemicals & Physics / Inorganic substances
Additive and advanced industrial manufacturing / Additive manufacturing processes and materials
Materials / Ceramic materials
Chemicals & Physics / Subtainable substances and green chemistry
Materials / Paper technology
Materials / Plastics, polymers

Bivalve mollusc shells are made mainly of CaCO3 (ca 95%), with a small fraction of organic material. If from these shells this mineral is retrieved, they could become a renewable and sustainable “mine” of a “blue” CaCO3. Bivalve mollusc shells, also after the removal of the animal flesh, maintain a certain quantity of organic substances, part in the muscle and part in the shell. Therefore, as the first step of the “blue” CaCO3 production, it is necessary to completely remove organic components, firing shells into an appropriate furnace after washing to remove salts. Successively, they have to be transformed at the form and dimensions specific for each expected product, grinding them by a suitable mill equipment. To maintain the carbon footprint, all the process has to be carried out in an engineered plant designed to operate using a green protocol. The waste resulting from the firing process could be reused further in the building sector, such as additive or admixture in lime mortars.

Type of innovation
Product innovation
Process innovation
Description of innovative features / Competitive advantages

At the moment, bivalve mollusc shells are not considered a waste that can be re-used, while they can represent a full-fledged renewable secondary raw material. A new regulation, followed at a local and national level, would be propaedeutic for the creation of a not yet existing value chain. In a perspective of circular economy, starting from the recovery of the shells a “blue” CaCO3 can be reached, absolutely renewable and sustainable, in contrast to that mined, which is currently used in every industrial  application. No attempt evaluated the use of a shell derived CaCO3 in any industrial fields to date, except building (unsustainable because of the big quantities required) and poultry feed. Possibile high added value applications can be in the production of paper, cosmetics and nutraceutics, plastics, glass, which conversely require limited quantities of CaCO3.

Reference market
Impacts on existing markets
Development stage
New product/process/service/technology
Patentable technology
Patented technology
Technology validation/demonstration
Internal validation
Market positioning
Partner required
Public research center/university
Private research center
Cooperation in national /european / international project

For more information and/or to be put in contact with the Research Team, please contact the Project Manager:

Barbara Angelini - Project Manager
CNR - Unità Valorizzazione della Ricerca
Phone number 06.49932415
E-mail barbara.angelini@cnr.it