In the present investigation, the oxidizing roasting process of chromite with sodium carbonate to prepare potassium dichromate crystals was studied in the microwave field with air, by heating the chromite and sodium carbonate. The chromite and sodium carbonate heated separately at 1000 ◦C in the microwave oven (frequency: 2.45 GHz; power 1.5 kW) in order to study the microwave absorption proper...

A series of experiments was performed to evaluate the effect of substituting sodium carbonate for the sodium hydroxide used in peroxide bleaching of spruce CTMP. Three peroxide levels were tested: I , 2, and 4% HzOz, and two levels of causticsubstitution; SO% and 80%. At both the 2% and 4% peroxide levels, substituting 50% of the caustic charge with sodium carbonate decreased the initial bright...

A surface-controlled dissolution of cylindrical solid particles model is applied to potassium carbonate, sodium bicarbonate and sodium carbonate in dimethylformamide at elevated temperatures. Previously published data for the dissolution of potassium carbonate is interpreted assuming a cylindrical rather than a spherical shape of the particles, the former representing a closer approximation to ...

We present the structure of anhydrous sodium carbonate at room temperature (phase gamma) and 110 K (phase delta) based on single-crystal X-ray diffraction data. The incommensurate phase gamma was determined almost 30 years ago in the harmonic approximation using one modulation wave and first-order satellites. In our work we use satellites up to fifth order and additional harmonic waves to model...

To reduce the risks of climate change, atmospheric concentrations of greenhouse gases must be lowered. Direct capture of CO2 from ambient air, ‘‘air capture’’, might be one of the few methods capable of systematically managing dispersed emissions. The most commonly proposed method for air capture is a wet scrubbing technique which absorbs CO2 in an alkaline absorbent, i.e. sodium hydroxide prod...

Introduction: Air-powder polishing devices are increasingly used for stain and plaque removal. However, besides cleaning the tooth surface, they may increase the surface roughness of the dental tissues. This in turn may result in plaque accumulation and superficial degradation. Thus the aim of this study was to assess the influence of three different abrasive agents: Pumice, Sodium bicarbonate ...

Cotton hanks were dyed with three different sulphur dyes using non-sulphide reducing agents such as glucose, fructose, invert sugar and molasses. The alkalies employed for reduction were sodium carbonate and sodium hydroxide. Invert sugar as a reducing agent and sodium carbonate as alkali proved to be better as this combination gave results comparable to those obtained with the conventional sod...

Oil recovery by waterflooding in fractured formations is often dependent on spontaneous imbibition. However, spontaneous imbibition is often insignificant in oil-wet, carbonate rocks. Sodium carbonate and anionic surfactant solutions are evaluated for enhancing oil recovery by spontaneous imbibition from oil-wet carbonate rocks. Crude-oil samples must be free of surface-active contaminants to b...

This study aims to investigate the activating effect of Na2CO3 and NaOH on the workability and mechanic strength of slag-based alkali activated materials with different alkali contents and water to binder ratios. The heat release during the reaction process of slag activated with sodium carbonate and sodium hydroxide were monitored respectively to analyze the hydration process. Meanwhile, the w...