Fast and Direct Microwave Synthesis of Carbon from Bovine Blood Waste: A Feedstock Material for Extractive Metallurgy, Carbon Dots Production and Graphite Synthesis

Author(s): Chalmpes N, Asimakopoulos G, Baikousi M, Moschovas D, Avgeropoulos A, Bourlinos AB, Sedajova V, Bakandritsos A, Gournis D, Karakassides MA.

Direct irradiation of slaughterhouse bovine blood waste in a domestic microwave oven results in fast carbonization and subsequent formation of carbon nanosheets at yield of 2% after copiously washing off any by-products. Since nearly 5 billion L of slaughterhouse bovine blood is globally produced every year as inevitable part of meat production, the total amount of carbon that could be annually produced by this simple and cost-effective microwave technology reaches the impressive value of 100,000 metric tons per year, albeit the relatively low carbon yield of the process. This large quantity of carbon with well-defined structure and composition could be further exploited in carbothermal extractive metallurgy (e.g., the extraction of copper from copper oxide) or as a cheap and plentiful raw material towards the production of other important carbon materials, such as photoluminescent carbon dots, synthetic graphite and graphene. The direct, simple and affordable microwave conversion of bovine blood waste into useful carbon material represents another example of blood waste valorization that is complementary to the extraction of bioactive compounds for the food or pharmaceuticals industry. It is interesting to note that the same microwave approach can be applied as well for the direct and fast carbonization of expired over the counter medicines, such-like drug effervescent tablets (e.g., analgesic paracetamol), giving carbon at high yield with useful properties (e.g., hexavalent chromium removal).