METHOD OF PRODUCTION OF NANODISPERSE ADDITIVE FOR CONCRETE Russian patent published in 2015 - IPC C04B24/00 C12N1/20 C12R1/01 

FIELD: biotechnologies.

SUBSTANCE: method of production of nanodisperse additive for concrete is offered. Cyanobacteria of the sort Pseudanabaena sp. 0411 or Leptolyngbya laminosa 0412 are cultivated in a nutrient medium at the temperature 23-25°C. The nutrient medium is Z-8 medium with adding of sodium silicate solution neutralized by 2 M HCl. Ratio of solution of silicate of sodium and Z-8 5:1 medium. Cultivation is carried out in the bioreactor at continuous lighting and mixing during 10 days with the subsequent removal of nutrient medium residue. Then the culture is poured by 30% hydrogen peroxide solution and heated up to 70°C. The produced biosilicated nanotubes are washed out by distilled water with subsequent treatment in a mechanical activator in the water medium of anion surface-active substance of naphthalene formaldehyde type at the ultrasound frequency 35 kHz and concentration of solid phase 5% up to the particle size 85-250 nanometres.

EFFECT: increase of mobility of concrete mix, curing acceleration, increase of strength and density of concrete, decrease of water absorption.

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