A novel approach for harvesting the microalgae Chlorella vulgaris with sodium alginate microspheres using buoy-bead flotation method

Re-frying oil emulsion as buoy-bead for microalgae harvesting: A promising approach for blooms of microalgae management

Blooms of microalgae can pose a major threat to ecological balance and human health. Therefore, a novel method of harvesting microalgae was investigated, using re-frying oil to make buoy-bead for the harvesting process. The effectiveness of the method was evaluated by water samples from the Huaihe River basin and Chaohu Lake. The results showed that the buoy-bead flotation method achieved a harvesting efficiency of 97.21 %.The climate change emissions for harvesting 1 m3 of microalgae are 0.33 kg CO2 eq, and with a positive NPV, the economic feasibility of the microalgae harvesting plan is preliminarily assessed.

Porous carboxymethyl cellulose nanocrystalline imprinted composite aerogels for selective adsorption of gadolinium

Gadolinium is widely applied in medical and high-tech materials because of special magnetic properties. Recovery of gadolinium from waste rare earth products has both economic and environmental value. In this experiment, honeycomb porous composite aerogels were constructed using sericin and sodium alginate mixed with functionally modified carboxymethylated cellulose nanocrystals for the adsorption and separation of gadolinium ions. There were large numbers of carboxyl groups as well as hydroxyl groups on the surface of sodium alginate and filamentous protein, which provided more sites for the adsorption of gadolinium ions. Besides, a stable honeycomb structure appeared on the surface of composite aerogels when the mixture of filamentous protein and sodium alginate was 1:1, which increased the specific surface area of materials to 140.65 m2 g-1. Additionally, the imprinted composite aerogels Ic-CNC/SSA were prepared by virtue of the imprinting technology, enhancing the adsorption selectivity of composite aerogels for gadolinium. The adsorption experiments revealed that the maximum adsorption capacity of Ic-CNC/SSA reached 93.41 mg g-1 at pH 7.0, indicating good selective adsorption of gadolinium ions. In summary, such composite aerogels provide great potential and reference value for the selective adsorption of gadolinium ions in industry.