Method of obtaining nanoparticles of biomorphic silicon dioxide from plant sections characteristic by the high content thereof

摘要

In the present invention, there is disclosed a method of obtaining nanoparticles of biomorphic silicon dioxide from plant sections, wherein the method is characterized in that the plant sections, without being preliminary treated in any manner, are put into a container of a microwave reactor with a microwave output of 1500 W at the most and 65 percent of nitric acid or containing aqua regia comprised of a mixture of three parts of the 65 percent nitric acid and one part of 38 percent hydrochloric acid, for a period of 50 minutes to 70 minutes. Subsequent decomposition reaction of the put plant sections runs in three continuous time intervals, whereby in the first time interval, lasting 15 minutes, is used for rise of temperature in the microwave reactor to the value in the range of 190 degC to 230 degC, a pressure rise to a value of 5.5 MPa at the maximum output of the microwave reactor of 1500, whereupon there follows the decomposition of the plant material for a period of 20 minutes to 40 minutes at a temperature of 230 degC, a pressure of 5.5 MPa and the microwave output of the reactor within the range of 600 W to 750 W. In the third time interval, after the microwave source is switched off, temperature is let to drop down to the value of about 75 degC and pressure to a value of about 0.5 MPa and the obtained nanoparticle agglomerates of the biomorphic silicon dioxide are washed with distilled water to a pH value of 7, and subsequently dried up. So obtained nanoparticles of biomorphic silicon dioxide of the decomposition process are henceforth kept either in an aqueous solution or dried to powder.