Acidic sulphur gases

Put a small amount of the obtained cobalt(III) oxide (what other cobalt oxide can form depending on the temperature ) into a test tube and treat it with concentrated hydrochloric acid. What gas evolves Write the equations of the reactions. How does cobalt(III) oxide react with nitric and sulphuric acids Write the equations of the reactions. 

The carbonyl sulphide is evolved at 20° C. together with hydrocyanic acid, formic acid and carbon disulphide. The gas is purified by passing through concentrated aqueous caustic potash to absorb the acid vapours, and the carbon disulphide is absorbed in a mixture of triethylphosphine, pyridine and nitrobenzene. After drying with sulphuric acid, the gas may be further purified by liquefaction or absorption in toluene.3... 

Ethylene is prepared from ethyl alcohol as in Prep. 9 or Prep. 436. The gas is passed first into an empty wash-bottle surrounded by a freezing mixture, and then through a second containing cone, sulphuric acid. The gas is next passed into antimony trichloride at 40°—50°, through... 

Unlike the RDE technique, which is quite popular for characterizing catalyst activities, the gas diffusion electrode (GDE) technique is not commonly used by fuel cell researchers in an electrochemical half-cell configuration. The fabrication of a house-made GDE is similar to the preparation of a membrane electrode assembly (MEA). In this fabrication, Nation membrane disks are first hot-washed successively in nitric acid, sulphuric acid, hydrogen peroxide, and ultra-pure water. The membranes are then coated with a very thin active layer and hot-pressed onto the gas diffusion layer (GDL) to obtain a Nation membrane assembly. The GDL (e.g., Toray paper) is very thin and porous, and thus the associated diffusion limitation is small enough to be ignored, which makes it possible to study the specific kinetic behaviour of the active layer [6],... 

Carbon dioxide gas. This gas can be obtained from a Kipp apparatus using calcium carbonate pieces (broken marble) and 1 1 hydrochloric acid. The gas should be washed with concentrated sulphuric acid. 

Congo Red Paper. Detection by means of this paper depends on the formation of hydrochloric acid by the decomposition of dichloroethyl sulphide with sulphuric acid. The gas to be examined is passed through a wash-bottle containing concentrated sulphuric acid at 55° C., and then over the Congo red test-paper. 

As scientists have learnt more about the way chemical constituents of the Earth s surface operate, it has become clear that it is insufficient to consider only individual environmental reservoirs. These reservoirs do not exist in isolation— there are large and continuous flows of chemicals between them. Furthermore, the outflow of material from one reservoir may have little effect on it, but can have a very large impact on the receiving reservoir. For example, the natural flow of reduced sulphur gas from the oceans to the atmosphere has essentially no impact on the chemistry of seawater, and yet has a major role in the acid-base chemistry of the atmosphere, as well as affecting the amount of cloud cover (Section 7.3). 

The spots are painted with a mixture of potassium chromate and hydrochloric acid. The gas used in this case is sulphur dioxide, which will be changed from yellow to green. The reader should experiment for himself in transformations of this nature, because the subject is obviously one that can be extended for instance, flowers, figures, etc., can be drawn upon silk with a solution of silver nitrate, when they are invisible. but if moistened and exposed to the action of hydrogen gas, then they become visible. Various chlorides, viz. chlorides of gold, tin, etc., can be similarly dealt with. 

A solution of sulphurous gas has no action upon it (Berthier) but, according to Goverant, a small quantity of the sulphide is attacked, with the production of hydrogen sulphide and sulphur. Dilute sulphuric acid has no action upon the sulphide crystals, but attacks... 

Three roasters operate in parallel to produce calcine. There are two 84-m fluidized bed roasters and a suspension roaster. Off-gas from the roasters is mixed with off-gas from the KIVCET furnace and is then processed in the sulphur gas handling area. By-products include calomel, sulphuric acid, liquid sulphur dioxide, and ammonium sulphate fertilizers. 

For NGL plants, emissions usually come from gas sweetening units when acid waste gas is burned or incinerated. Most frequently, the acid waste gas is used as a feedstock in sulphur recovery units or in sulphuric acid plants. While flaring is often expected in NGL plants, the major poison and pollutant of concern is S02- Most plants employ elevated smokeless flares or gas incinerators for combustion of all waste gas constituent, including tail gas incinerator in which H2S is oxidized to SO2 (Berkel, 2000) [7]. Such practices are not sustainable. CP can be implemented to reduce and/or eliminate gas flaring or incinerations beyond acceptable level as stipulated by local environment authorities. 

---