Nitrogen as a Catalyst in the Determination of Sulfur in Coal by the

was claimed in the patent that it reads like a prophetic vision of our own day. Unquestionably, the great significance of the earliest studies on the ...
3 downloads 0 Views 277KB Size
September, 1927

IXDUSTRIA L A X D ENGINEERIXG CHEMISTRY

was claimed in the patent that it reads like a prophetic vision of our own day. Unquestionably, the great significance of the earliest studies on the reaction lay in the secure foundation which had been built for an enormous development in

1065

synthetical, theoretical, and industrial organic chemistry. The fiftieth anniversary of the discovery witnesses great and vigorous growth in the importance and use of the FriedelCrafts reaction.

Nitrogen as a Catalyst in the Determination of Sulfur in Coal b y the Bomb-Washing Method' By J. F. Kohout COMMERCIAL TESTING ASD ENGINEERING C o . , CHIC.&GO, ILL.

T T H E meeting of Committee D-5 of the. American

A

Society for Testing Materials held in Pittsburgh, Pa., in Il'orember, 1926, three methods for the determination of sulfur in coal were presented-namely, the Eschka. the sodium peroxide fusion, and the bomb-washing method.* The Eschka and sodium peroxide methods give results which are very slightly higher than the bomb-mashing method as ordinarily used. This paper deals with the bonib-washing method alone, and shows how the bomb-washing method may be brought into agreement with the other two methods. Some form of catalytic agent is required for the complete oxidation of sulfur to sulfuric acid by combustion processes. This is true whether the sulfur is being burned in a large commercial sulfuric acid plant or in an oxygen bomb calorimeter. The catalysts usually employed in the acid plants are platinum or platinized asbestos or oxides of' nitrogen. In the oxygen bomb the oxides of nitrogen are the agents used. This function of the oxides of nitrogen was shown by R e g e ~ t e r . ~This nitrogen ordinarily comes from the coal and from the air in the bomb. Part of it is oxidized when the coal or coke burns in the bomb charged with oxygen under pressure. The oxides of nitrogen form the catalytic agent required for the conversion of the sulfur. The American Society for Testing Materials in its method for calorimetric determination on coal4 specifies that at least 5 per cent of nitrogen be present in the bomb atmosphere. Since a small part of the nitrogen is oxidized in the bomb, it was thought that by increasing the total amount of nitrogen in the atmosphere in the bomb to 10 or 15 per cent the amount of oxides of nitrogen formed would be increased. This increased quantity of mixed oxides insures the complete oxidation of the sulfur in the coal or coke to sulfuric acid in 5 minutes. This is the average length of the combustion period in a heat value determination as made by any standard oxygen bomb calorimeter. Sulfur Determinations

A Parr illium bomb of 3iO cc. capacity was used, 0.5 cc. of water being placed in the bomb to absorb the acids formed when the 1-gram sample was burned. When oxygen alone was used the pressure in the bomb was 22 atmospheres. When the nitrogen-oxygen mixture was used the nitrogen was run into the bomb to a pressure of 3 atmospheres, and the total pressure in the bomb was then increased to 25 atmospheres with oxygen. The nitrogen and oxygen cylinders were connected to the pressure gage and bomb union with a T connection, so that 1 Presented before t h e Division of Gas a n d Fuel Chemiitry at t h e i3rd Neeting of t h e dmerican Chemical Society, Richmond, V.1 April 11 to lb, 1927 2 Selvig a n d Fieldner, THIS JOURNAL, 19, 729 (1927). I b r d . , 6, 812 (1914) 4 Am SOCTestrng Matenals, Standards, p. 1008 (1924).

either oxygen or nitrogen could be introduced into the bomb without disconnecting it. After ignition the bomb was allowed to stand in water for 5 minutes. i i t the end of this time the gases were slowly released from the interior, so that the pressure in the bomb fell to atmospheric in about 2 to 3 minutes. The interior of the bomb, including the valve, was thoroughly washed with distilled water containing 1 cc. of saturated methyl orange solution to 1 liter of water, until the indicator gave no test for acid. The washings were neutralized with sodium carbonate solution, 2 cc. of ammonia water were added, and the solution mas boiled and filtered. The filtrate was acidified with hydrochloric acid, 3 cc. of bromine water were added, and the solution was boiled to expel the bromine. Ammonia was added t o neutrality and then 1 cc. of concentrated hydrochloric acid was added, and the solution heated to boiling. The sulfur was precipitated in the boiling solution with hot 10 per cent barium chloride solution. The barium sulfate was allowed to settle in the hot solution for about 2 hours, and was then filtered out, ignited, and weighed. Table I-Per

Cent Sulfur in Coal

(Figures on d r y basis) OXY-

OXYGEN AND NITROGEX

OXYGEN AND

OXY-

GEN

DIFF.

NITROGEN

DIFR. 1.17 1.17 21 0.00 0.68 0.67 -0.01 22 0.56 -0.02 1.71 0.58 1.70 t o , 01 2.25 23 2.23 0.60 0.61 +0.01 +0.02 24 3.65 8.01 8.08 +0.07 3.69 A0.04 4.47 4.55 4.62 25 4.49 + O . 13 t0.08 5.55 5 63 26 + O . 10 5.20 tO.08 5.36 2.59 2.61 6.64 27 6.64 to.02 0.00 1.36 28 1.38 +0.02 6.83 6.65 t o . 18 1.89 29 1.88 6.71 -0.01 6 64 t0.07 10 6.32 6.31 -0.01 30 3.87 3.77 f O . 10 3.11 11 3.19 31 1.92 1.88 tO.08 f0.04 12 5.12 32 5.35 3.14 3.12 tO.02 r0.23 13 6.47 +o. 15 6.62 33 0.74 0.78 -0.04 14 6.19 6.29 34 2.64 2.58 +0.10 ~ 0 . 0 6 15 35 0.97 0.96 -0.01 1.85 1.85 0.00 16 0.55 -0.01 0.54 36 1.55 1.41 4-0.14 17 3.46 0.00 3.46 37 0.97 0.91 0.00 18 3.69 38 0.78 +0.07 3.76 0.77 -0.01 1 16 19 1.16 39 5.22 5.02 0.00 to.20 20 0.79 0.79 0.00 40 0.80 0.80 0.00 a All coals were bituminous except 1 , 2, 16, a n d 40, which were semibituminous, a n d 3, which was coke.

SAMPLE'

S4MPLEa

GEN

1 2 3 4 5 6 7 8 9

It will be noted from Table I that in most cases the effect of the added nitrogen was to increase slightly the amount of sulfur obtained. The exceptions where a decrease is shown are low-sulfur coals, and the differences are so small that either value could be taken as the true percentage of sulfur. The increase is generally most marked in the coals of high sulfur content. The values in the table are the averages of two or more determinations. Determination of Heat Values

The heat values of the last five coals (36 to 40, inclusive) were determined to see if the added nitrogen interfered in any way with the B. t. u. determination. The results (Table

1066

I,YDCSTRIAL A-YD ESGIAITEERINGCHEMISTRY

Vol. 19, No. 9

11) indicate t’hat no complication is introduced, and check as closely as could be desired.

sulfur overcame the effect of the greater rise in temperature. The washings were titrated with a sodium carbonate solution (3.658 grams per liter of water) to determine the acidity correction. From 13 t o 17 cc. more solution were required to sOLN. neutralize the bomb washings when the nitrogen was used.

T a b l e 11-Heat Values (Figures on dry basis) BRITISHTHERMAL ( T N I T ~U,S I X ~ : TITBR,cc. Na2C03 Oxyqen Oxygen and and SAMPI.$ Oxygen Xitrogen Diff. Oxygen Nitrogen Increase 36 13,013 13,011 39 7. 0 14 1 3 .00 37 13,288 13,276 9 4 23 6.0 38 13.801 13,814 13 21.0 35.0 14.0 39 12,136 12,120 16 50,s 64.5 14.0 40 14,914 14,903 11 22.0 39.0 17.0

The total heat liberated in the calorimeter was greater when the nitrogen was used, but the washings from the bomb were more strongly acid, so that the correction for acid and

Conclusions The effect of added nitrogen in the oxygen bomb calorimet’er is to increase slightly the amount of sulfur obtained by the bomb-washing method for the determination of the sulfur in coal and to bring the results obtained by the three methods generally used for the determination into substantial agreement. No complication in the heat value determination is introduced thereby.

F. J. Moore-Historian of Chemistry’ By Tenney L. Davis XASSACHUSETTS INSTITUTE OF TECHNOLOGY, CAXBRIDGE, MASS.

A

F. J.

Moore

LL American

students of the h i s t o r y of chemistry are familiar w i t h Moore‘s book upon t h e s u b j e c t . Many owe to it their first interest in the history of their science. But only a few of us have had the privilege of a personal acquaintance with its genial author. Prof. Forris Jewett Moore died s u d d e n l y on November 20, 1926, at his home in Camb r i d g e , Mass. The acconipanying portrait is r e p r o d u c e d from a p h o t o g r a p h

but he rethined his research assistants and visited the laboratory frequently for conference with students who were working under his direction for the doctor’s degree. Professor Moore considered himself to be an alchemist sort of a chemist, for he preferred to examine new territory and to study new permutations and combinations of atoms, His published researches deal with the sulfocinnamic acids, with colored salts of Schiff’s bases, with the constitution of xanthogallol, and with the oxidation of uric acid by means of hydrogen peroxide. They show throughout that mastery of innumerable detail which is necessary for pioneer work in structural organic chemistry. He published “Outlines of Organic Chemistry” (1910), “Experiments in Organic Chemistry” (1911), and “A History of Chemistry” (1918). The last book shows the character of the man-widely read, witty, and lucid. It is entertainingly written and can be recommended to chemist and non-chemist alike. The writer has found it excellent medicine for the student who thinks that organic chemistry is difficult, for it gives him an interest which removes difficulties and makes intricacies appealing. As an undergraduate a t Amherst, F. J. Moorewas interested in chemistry and in philosophy-to such an extent that he found it difficult to choose between the two. Although he decided to pursue the chemistry, his “History of Chemistry” makes it clear that he never abandoned the philosophy.

taken ten davs before that date. F. J. Moork was born a t Pittsfield, Mass., June 9, 1867. He graduated from the Stevens High School of Claremont, K. H., in 1884, and received the degree of bachelor of arts from Amherst College in 1889. At Amherst he studied chemK j eldahl Digestion Apparatus istry with Prof. William P. Harris, and after graduation conEditor of Industrial and Engineering Chemistry: tinued a t that college for another year as a teacher in the laboratory. He then went to the University of Heidelberg, We feel that i t would be undesirable to go into a discussion where he studied with Victor Meyer and with Gattermann, concerning the patentable features of the Kjeldahl apparatus carried out under the direction of the latter his doctor’s re- described by us [E. G. Hastings, E. B. Fred, and W. H. search on the isolation of the aromatic sulfonic acids, and was Peterscn, THIS JOURXAL, 19, 397 (1927)] and referred to by awarded the degree of doctor of philosophy in 1893. In 1892 W. H. Scott [THIS JOURNAL, 19, 761 (1927)l. Apart from the he married Miss Emma Tod of Edinburgh, Scotland. After sliding lead stopper, our apparatus does not possess any new returning to the United States he served for one year as in- or novel feature. The idea of a fume tube with side arms is structor of chemistry at Cornel1 University. In the autumn old and well known. See Merkle [THISJOURNAL, 8,521 (1916)]. of 1894 he came to the Massachusetts Institute of Technol- The absorption of the fumes and their discharge into a sewer ogy. Here he first taught analytical chemistry, but soon is also old and well known. See Sy [THISJOURNAL, 4,680 (1912) 1. transferred to the organic chemistry section of the chemistry THEUNIVERSITY OF WISCONSIN E. B. FRED COLLEGE OF AGRICCJLTURE department, where for many years he was in charge of underMADISON, WIS. April 4 , 1927 graduate instruction in that subject. The condition of his health caused him to retire from active teaching in 1925, 1 Presented under the title “Two Portraits of F. J. Moore, Historian of Chemistry” before t h e Section of History of Chemistry a t t h e i 3 r d Meeting of the American Chemical Society, Richmond, Va., April 11 to 16, 1921.

Correction-In the article on “By-product Hydrochloric Acid” by E. J. Fox and C. W. Whittaker, THISJOURNAL, 19, 349 (1927), the patent number in footnote 3 should be 1,235,025.