HomeTIP Research Journal Quezon Cityvol. 4 no. 1 (2007)

The Potential of Calcium Carbonate from Philippine Green Mussel Shells as Extender in the Manufacture of Flat Latex Paints

Yvonne Ligaya F. Musico

Discipline: Chemistry, Chemical Engineering



The potential of calcium carbonate from “tahong” shells as an extender for flat latex paint production was investigated through this study.


Perna viridis, commonly known as the Philippine mussel (tahong), is a bivalve mussel widely distributed in the Asia-Pacific region. The green mussel shells, that have greatly contributed to the tons of solid wastes generated in the region, proved to be useful when utilized in the production of calcium carbonate, as an extender in producing flat latex paint.


Green mussel shells were screened, calcinated and used as an extender-substitute for a commercial calcium carbonate for flat latex paints. Calcined “tahong” shells appear to be very white, which were as white as the commercial calcium carbonate. Their grains were categorized as fine since they had a particle size of 2 m. Calcined green mussel shells are basic (pH = 14.4). Their oil absorption (50.65 g/100 g) is greater than that of commercial calcium carbonate (26.79 g/100 g). This results to a high viscosity of “tahong” shells calcium carbonate, which is 215 k. Infrared (IR) spectroscopy reveals that the correlation of calcined “tahong” shells to commercial calcium carbonate is 20% only.


This was due to some unidentified impurities of the calcined shells. Despite the low correlation, calcium carbonate from green mussel shells exhibits some positive performance when used as an extender for flat latex paint. Paints with “tahong” shells calcium carbonate, have good hiding capacity. Paints using calcium carbonate from “tahong” shells gave smoother surface and gloss than those of commercial calcium carbonate. Though acknowledged that the adhesion property of calcined tahong was inferior compared to the commercial carbon carbonate, this study proved true that the calcium carbonate from “tahong” shells exhibited positive properties of an extender for flat latex paint.