Sodium plumbite

Sulfur compounds No reaction at sodium plumbite test (NF M 41-006) Pass hydrogen sulfide test (ISO 8819, future NF EN 28819)... 

Sulfur (detection of H2S and mercaptans) ( Doctor Test ) NF M 07-029 ASTM D 325 Sodium plumbite test (coloration of interface)... 

Sulphur, as sulphide ion, is detected by precipitation as black lead sulphide with lead acetate solution and acetic acid or with sodium plumbite solution (an alkaLine solution of lead acetate). Halogens are detected as the characteristic silver halides by the addition of silver nitrate solution and dilute nitric acid the interfering influence of sulphide and cyanide ions in the latter tests are discussed under the individual elements. 

Prepare a solution of sodium plumbite by adding 10 per cent, sodium hydroxide solution to a few drops of about N lead acetate solution until the white precipitate of lead hydroxide initially formed just redissolves to a clear solution. Add 1 ml. of the fusion solution the presence of sulphiu- is indicated by a black precipitate of lead sulphide. 

When an organic compound is heated with a mixture of zinc powder and sodium carbonate, the nitrogen and halogens are converted into sodium cyanide and sodium hahdes respectively, and the sulphur into zinc sulphide (insoluble in water). The sodium cyanide and sodium hahdes are extracted with water and detected as in Lassaigne s method, whilst the zinc sulphide in the residue is decomposed with dilute acid and the hydrogen sulphide is identified with sodium plumbite or lead acetate paper. The test for nitrogen is thus not affected by the presence of sulphur this constitutes an advantage of the method. 

Sulphur. Moisten the centre of a filter paper with sodium plumbite solution. Add about 10 ml. of dilute hydrochloric acid to the residue in the dish and immediately cover it with the prepared filter paper. If zinc sulphide is present in the residue, a dark brown stain, visible on the upper surface of the paper, will be obtained frequently the presence of hydrogen sulphide can also be detected by its odour. 

To effectively remove carbonyl sulfide from a gas stream, special alkaline scmbbiag Hquors are used. These contain sodium aluminate or sodium plumbite, or they are made of alkaUes with a hydrolysis catalyst based on Zn, Fe, Ni, or Cu. Diethanolamine, diglycolamine, or other alkanolamines (qv) mixed with water remove carbonyl sulfide from sour, ie, acid-gas-containing, gas streams (25,26) (see Carbon dioxide). 

The process wherein sodium plumbite is used to remove mercaptans this is also known as the Doctor s treatment ... 

Doktor Also spelled Doctor. A process for deodorizing oils by converting trace mercaptans to disulfides by the use of alkaline sodium plumbite and sulfur. The reactions are ... 

Other waste streams from the process result from water washing of the treated product and regeneration of the treating solution such as sodium plumbite (Na2Pb02) in doctor sweetening. These waste streams contain small amounts of oil and the treating material, such as sodium plumbite (or copper from copper chloride sweetening). 

Lead trioxide is prepared by adding sodium hypochlorite or bromine to an aqueous solution of sodium plumbite. 

Hydroxy-l,2,4-thiadiazoles possess phenolic character they give red to purple colors with ferric chloride, and fail to afford ketonic derivatives.130,178 They resist the action of hot alkaline sodium plumbite.130 The 3-alkoxy homologs are neither alkali soluble nor give colors with ferric chloride.130... 

In general, substituted 3,5-diamino-l,2,4-thiadiazoles resist the action of alkaline sodium plumbite,50,1U 125 except the parent compound110 which deposits lead sulfide on brief warming. 

Arylamino-3-nitroamino-l,2,4-thiadiazoles are crystalline solids which explode at their melting points. They are monobasic acids, remarkably stable to alkalis and to the action of boiling sodium plumbite. Mild reduction by sulfur dioxide reconverts 5-anilino-3-nitroamino-l,2,4-thiadiazole into its parent amidinothiourea from which it arises by oxidation. Attempts to reduce 3-nitroamino compounds to the corresponding 3-hydrazines were not successful.141... 

Sodium plumbite solution, 1041 Sodium press, 164 Sodium sulphide, anhydrous, 197 use of, 574, 587... 

Against this latter view is the fact that little or no sulphuric acid is formed unless the mixture is boiled for a long time. In alkaline solution, alkali sulphide and trithionate react to form thiosulphate,1 but alkaline solutions of sulphate and sulphide do not.2 It would appear, therefore, that the correct explanation lies in the reversible equation (6) (p. 195). This receives support from the fact that when lead thiosulphate is boiled with water it yields, in the first instance, lead sulphide and lead trithionate.3 Conversely, lead sulphide on digestion with potassium trithionate yields lead thiosulphate.4 Further, weakly alkaline solutions of sodium thiosulphate itself yield, on boiling, sodium sulphide and sodium trithionate, with only a trace of sulphate if boiled with sodium plumbite, lead sulphide is precipitated and sodium trithionate remains in solution. 

Doctor solution a solution of sodium plumbite used to treat gasoline or other light petroleum distillates to remove mercaptan sulfur see also Doctor test. 

Doctor sweetening a process for sweetening gasoline, solvents, and kerosene by converting mercaptans to disulfides using sodium plumbite and sulfur. 

Doctor test a test used for the detection of compounds in light petroleum distillates that react with sodium plumbite see also Doctor solution. 

Sodium plumbite a solution prepared from a mixture of sodium hydroxide, lead oxide, and distilled water used in making the doctor test for light oils such as gasoline and kerosine. 

Sodium stannite and sodium plumbite both hydrolyze easily but the latter much more so, consequently the greater amount of base to overcome its tendency to hydrolyze. 

Lead dioxide, PbOg, is a brown substance made by oxidizing a solution of sodium plumbite, NaoPb(OH)4, with hypochlorite ion, or by anodic oxidation of lead sulfate. It is soluble in sodium "hydroxide and potassium hydroxide, forming the hexahydroxyplumbate ion, Pb(OH)g—. The principal use of lead dioxide is in the lead storage battery (Chap. 14). 

Dilute one drop of the alkaline solution with 1 mL of water and add a drop of sodium nitroprusside a purple coloration indicates the presence of sulfur. (2) Prepare a fresh solution of sodium plumbite by adding 10% sodium hydroxide solution to 0.2 mL of 0.1 M lead acetate solution until the precipitate just dissolves, and add 0.5 mL of the alkaline test solution. A black precipitate or a colloidal brown suspension indicates the presence of sulfur. 

Ibid., No. 12, p. 113. Part II, Analysis of Sulfur Compounds in Light Petroleum Distillates. Ibid. 30, No. 1, 129 (1951). Part III, Sodium Plumbite Treatment. 

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