2 research outputs found
Synthesis, Characterisation and Testing of Bismuth Vanadate – An Eco-friendly Yellow Pigment
833-837Bismuth based pigments are environmentally
friendly and can replace more hazardous yellow formulations containing lead, chromium
or cadmium pigments. They offer brilliant greenish yellow and orange shades with
high opacity and high colour strength. An improved method is developed for the preparation
of bismuth vanadate from an aqueous solution of sodium vanadate by adding a solution
of bismuth nitrate in the presence of sodium acetate/acetic acid buffer. This avoids
the polymerisation of vanadate ion in acidic solution as well as the formation
of bismuthyl ion in alkaline solution. The pigment is characterised by
measuring its bulk density, particle size, and oil absorption value. Its colour
is matched with colours of
standard yellow and orange pigments. An XRD
study is also carried out which indicates the pigment to be of monoclinic form