Chapter

Sodium Carbonate

Authors:
To read the full-text of this research, you can request a copy directly from the author.

Abstract

Sodium carbonate, also known as soda ash, is an alkali chemical refined from the mineral trona or naturally occurring sodium carbonate brines. The product is called natural soda ash. Synthetic soda ash is manufactured by several chemical processes. Production from trona and the Solvay synthetic process account for the vast majority of current capacity. The United States has the world's largest deposit of trona. Sodium carbonate is a moderate health hazard. The major use of soda ash is in the manufacture of glass. Other uses are the manufacture of chemicals, in detergent formulations, flue gas desulfurization, and in the production of paper and pulp

No full-text available

Request Full-text Paper PDF

To read the full-text of this research,
you can request a copy directly from the author.

... Production from trona accounts for the vast majority of current capacity. The United States has the world's largest deposit of trona [6] . ...
... Sodium carbonate has a large use in industrial area. The major use of sodium carbonate is in the manufacturing of glass [6] . Dry laundry detergent typically contains 20% to 80% sodium carbonate. ...
Chapter
Sodium sulfate (Na 2 SO 4 ) and/or calcium sulfate (CaSO 4 ) are often produced as waste materials by the mining and fertilizer industries. However, valuable products such as sulphur Na 2 CO 3 , nano CaCO 3 and NaHS can be recovered from these salts. Na 2 CO 3 is used for mine water treatment and glass manufacturing with a current price of R4 500/t (US$345/t). CaCO 3 is used, among other applications, as a filler in the paper and pharmaceutical industries. Two new technologies were evaluated for the production of Na 2 CO 3 from Na 2 SO 4 . The one technology based on carbothermal reduction of Na 2 SO 4 to produce Na 2 S as intermediate is not convenient due to the melting of mixtures of Na 2 SO 4 at the reaction temperature. As a result of this complication, an alternative technology coined the Sulfide/Carbonate process was proposed. In this process, calcium sulfide (CaS) produced through thermal reduction of gypsum with coal at 1000 °C was used as an intermediate reactant and evaluated for the production of Na 2 S from Na 2 SO 4 . Furthermore, it was also proposed to use CaS for the production of nano CaCO 3 . The Freeze Crystallization process (University of Limpopo) was used for the conversion of Na 2 S to NaHCO 3 and NaHS. These developments have completed the search for technological solutions that will result in zero waste during mine water treatment.
Article
In this study, calcium carbonate has been produced continuously using synthetic soda ash industry liquid waste with different process variables. The effect of process variables such as gas flow rate (1000 to 4000 ml/min), waste liquid flow rate (80 to 280 ml/min), CO2 concentration (20% to 40%), ultrasonic probe area (2.83 to 4.90 cm²), ultrasonic probe immersion depth (2/3 h to 1/2 h), ultrasonic power (0% to 70%), and reaction temperature (30°C to 50°C) on product quality was investigated by using D-optimal design. According to the experimental results, precipitated calcium carbonate (PCC) having different particle sizes (D (4:3)) ranging from 2.9 µm to 8.7 µm was obtained. It was observed that crystal structure of product is highly dependent on the pH of reaction medium. While vaterite and aragonite crystal structure were formed at low pH values, calcite crystal structure was formed at higher pH values. Particle size decreases when ultrasound power applied at 35% when compared to silent reactions. Overall, precipitated CaCO3 with desired particle size and crystal type can be produced by controlling the process variables. The CaCO3 was produced in amounts ranging from 3.4 g to 11 g depending on the experimental conditions.