Classification of sodium bicarbonate
(1) Classification of sodium bicarbonate
1. According to the difference in density, sodium bicarbonate is mainly divided into light sodium bicarbonate (hereinafter referred to as light alkali) and heavy sodium bicarbonate (hereinafter referred to as heavy alkali). Its components are all sodium carbonate, but the physical shape is different: the density of light alkali is 500-600kg / m3, white crystal powder; heavy alkali density is 1000-1200kg / m3, showing white fine particles. Unlike light alkali, heavy alkali has the characteristics of firmness, large particles, high density, low moisture absorption, not easy to agglomerate, not easy to fly poplar, and good fluidity. In addition, it is also ultra-light sodium bicarbonate and super-heavy sodium bicarbonate with densities of 370kg / m3 up and down and 1550-2553kg / m3.
2. According to different uses, sodium bicarbonate can be divided into industrial sodium bicarbonate and edible sodium bicarbonate. Industrial sodium bicarbonate implements the national standard GB / T210-2004 of the People's Republic of China (hereinafter referred to as the national standard), including GB / T210.1-2004 industrial sodium carbonate test method part I and GB / T210.2-2004 industrial sodium carbonate test method part II. Edible sodium bicarbonate is the standard of GB1886-1992 sodium carbonate for food additives. It has added arsenic and heavy metal content limits on the basis of reaching the industrial sodium bicarbonate low salt alkali standard.
3. According to the content of chloride, sodium bicarbonate can be divided into common alkali, low salt alkali, ultra-low salt alkali, special low salt alkali. According to national standards, the mass fraction of common alkali sodium chloride is ≤1.20%, the mass fraction of low salt alkali sodium chloride is ≤0.90%, the mass fraction of ultra-low salt alkali sodium chloride is ≤0.70%, and the special low salt alkali sodium chloride The quality score is ≤0.30%.
