Sodium carbonate, molten

It is also attacked by the Lewis base OH in hot, molten sodium hydroxide and by O2- from the carbonate anion of hot molten sodium carbonate ... 

The causes of furnace blasts occurring in soda-regeneration plants when water is spilt into molten sodium carbonate, sodium chloride, sodium hydroxide, sodium sulfate or sodium sulfide are discussed, together with methods of prevention. 

Laboratory investigations into the mechanism of smelt-water explosive boiling events have been primarily of value in delineating the effect of smelt composition on the sensitivity of the salt in producing RPTs. For example, pure molten sodium carbonate has never led to explosive boiling. Addition of either (or both) sodium chloride or sodium sulfide lead to smelts which are more prone to explosive boiling. Investigators experimented with many additives both to the smelt and to the water in an attempt to obtain less sensitivity. Most had little or no effect. 

Molten salt is a technique that has been considered for the destruction of pesticides and other hazardous wastes for several years. In a recent study by Rockwell International for EPA (1 ), the destruction of solid hexachlorobenzene (HCB) and liquid chlordane exceeded 99.99% in a molten sodium carbonate bath at 900 to 1000°C with a residence time of 0.75 s. For the pilot-scale tests, the concentration of HCB and chlordane in the spent melt was < 1 ppm. The HCl concentration in the off-gas was < 100 ppm. 

Examples of destructive agents are a solution of HF (for most silicates), molten sodium carbonate (Na2C03) and molten potassium disulphate... 

M.W. Kellogg Company uses molten sodium carbonates demonstrated. 

Atomics International uses molten sodium carbonates hydrogen and carbon monoxide not differentiated demonstrated. 

Kroger (3) found that metallic oxides and alkali carbonates or mixtures catalyzed the carbon-steam reactions. Lewis and co-workers (4) stated that if reactive carbons are catalyzed with alkali carbonates, reasonable gasification rates are attainable at temperatures as low as 650 °C. A process which uses molten sodium carbonate to catalyze as well as to supply heat for the carbon-steam gasification has been described (5). 

Cells have been built based on the oxidation of carbon to carbon dioxide. Relatively high temperatures are required (500 to 700 °C). One version uses a molten sodium carbonate electrolyte. The reactions are ... 

T. Ttomson said that potassium dictromate has a cooling, bitter, metallic taste it is stable in air, and is not hygroscopic. V. Ipatieff and A. Kisseleff found that when 2iV-K2Cr207 with some cone, sulphuric acid is exposed to hydrogen at 180° to 200 atm. press., a crystalUne compound, K20.Cr203.Cr2(S04)3.H20, is formed. It is insoluble in acid, and is dissolved by molten sodium carbonate and potassium nitrate. 

In another method, exhaust gases containing SO2 are passed through molten sodium carbonate and solid sodium sulfite is formed (Figure 4.5). 

FIGURE 4.5 Removal of SO2 from flue gas by reaction with molten sodium carbonate. 

The dry spent absorbent is mixed with carbon (petroleum coke or coal) and fed into a refractory-lined reducer vessel that contains a pool of molten sodium carbonate and sodium sulfide at a temperature of about 1,800°F. Air is injected to oxidize part of the carbon to CO and CO2 in order to provide the heat needed by the endothermic reduction reactions and maintain the overall system at the reaction temperature. 

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