Paper, tests sulfonation

The optimum temperature for simple arylamines is 0-2°, for m-haloaryl-amines 0-5°, and for benzidines, naphthylamines, and o- and / -haloarylamines 10-12°. In isolated cases higher temperatures are used, e.g., 34° for / -nitro-aniline and 40° for o-anisidine. The end-point of the reaction is determined by testing for an excess of nitrous acid with potassium iodide-starch paper. Amino sulfonic acids are no longer used to remove the excess of nitrous acid since they react with reactive diazo compounds.244... 

In this method, an ale soln of benzene-sulfonic acid(previously standardized with phosgene by weighing the pptd diphenyl-carbamide) is added from a burette to a sample of aniline(or its nitrated compd not jiighvr thsji tctrsnitro-) until the 3ppcufuptcc of a dirty-bluish coloration, when a drop of the reaction mist is placed on a filter paper previously impregnated with amino-/3-naphthol indicator(spot test). This method is not applicable for analysis of penta-nitroani ine(Ref 15)... 

It can be prepared either by using appropriate direct dyes or reactive dyes. In the latter case, pure linters (the raw material for high-quality paper) are suspended in water, and the solution of the reactive dye is added. For example, the dye 15 reacts via the sulfonic acid group in the side chain. The reaction mixture is then made alkaline and the dye reacts with the linters. After completion of the reaction, the fiber pulp is centrifuged, washed electrolyte-free, and processed on a paper machine to form the pH paper. Paper produced in this way is mostly bonded onto a plastic material and used as pH test strip. 

Brauns FE, Brauns DA (1960) The sulfonation of lignin In Brauns FE, Brauns DA (eds) The chemistry of lignin Supplement volume Academic Press, New York, 313-386 Canadian Pulp and Paper Association (1970) Standard Method G28 In Standard Testing Methods, Technical Section, Canadian Pulp and Paper Association, Montreal, Canada Canadian Pulp and Paper Association Useful Method G 7U In Standard Testing Methods, Technical Section, Canadian Pulp and Paper Association, Montreal, Canada Cappelen H, Schoon N-H (1966) Determination of sulfonic acid groups in unbleached sulfite pulps Sven Papperstidn 69 322-325... 

Clayton yellow paper (thiazole paper) is paper impregnated with the dye formed by coupling diazotized primuline sulfonic acid with primuline sulfonic acid. The color change occurs at pH 11-12. If this paper is not available, a little less than the estimated amount of alkali should be used. The mixture is warmed to 85 and a small test portion is removed and warmed with more alkali. If any appreciable amount of the insoluble matter dissolves, more alkali is needed. 

The nitrobenzene solution, together with the suspended solid material, is shaken with a mixture of 300 cc. water and 100 grams of ice, then twice with 100-cc. portions of cold water. The combined aqueous extracts are filtered through a moistened paper and then saturated with 200 grams of salt, whereupon sodium 2-naphthol-l-sulfonate is precipitated in colorless plates. Stirring is continued until all of the salt is dissolved, and the mixture is allowed to stand overnight, then filtered. The product is pressed out and washed twice with saturated salt solution. The filter cake is used directly for the preparation of 2-naphthyl-amine-l-sulfonic acid after tests have shown that it does not fluoresce in soda solution and does not yield a water soluble, orange red dye with diazotized aniline and thus does not contain isomeric naphtholsul-fonic acids. 

Buijse, M.A., Prelicz, R.M., Barnes, J.R., Cosmo, C., 2010. Application of internal olefin sulfonates and other surfactants to EOR. Part 2 the design and execution of an ASP field test. Paper SPE 129769 presented at the SPE Improved Oil Recovery Symposium, Tulsa, 24-28 April. 

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