ELECTROANALYSIS S-IJICEL E. Q . ASHLEY Transfortrier and Allied Products Division Laboratory, General Electric Co., Pittsjield, Mass.
T
HE present article is a continuation of the last review (2), and covers the major work of 1949 and 1950 and a large part of 1951, as well as material published earlier but not available until after the last review waa written. In comparing the literature reviewed it is interesting t o discover that, although the preaent paper covers a shorter period, there is a very considerable increase in the number of publications in this field. That this is greater than the 17’% increase in all technical publication, and is not entirely the result of the declassification of secret wartime documents, can be discovered by qualitatively examining the names of the contributors and theindividual papers. Thebibliography shows that electroanalysis is increasingly occupying the time and efforts of leaders in analytical chemistry, and has attracted new investigators, who have devoted considerable effort t o the preparation of individual aeries of articles. .4t the same time, many familiar authors continue actively in this field This betokens a healthy condition for a well developed area of analytical chemistry which was for a time thought t o be “worked out.’‘
istry are briefly reviewed by Phillips (185). Other specialized reviews are referred to under the specific topics they cover, THEORY
The peculiar conditions that surround electrochemical processes occurring during the procedures of electroanalysis have been the subject of special study by several analytical chemists, No attempt is made here t o review the development of electrochemical theory as it applies to electrode processes, either in the general field of electrochemistry or in cognate branches of analytical chemistry. Rogers and Stehney (132) have found that the Kernst equation can be modified todescribe the deposition of ions of very low concentration on an inert electrode. The kinetics and thermodynamics of electroanalytical determinations have been investigated by Schleicher (138, 139, 141). Haissinsky (42, 43) has continued work begun earlier t o elucidate the mechanism of deposition processes on a solid electrode by the use of naturally radioactive isotopes. He explains his results by postulating active centers on the electrode surfaces.
BOOKS
EQUIPMENT
S o recent books are devoted entirely to electroanalysis, al-
A power unit designed to rectify an alternating current power supply for use in micro scale electrolysis has been described by Marion (85). Rabbitts (137) has described a six-unit stand for electrodeposition by which stirring is effected within the beaker by an iron slug sealed in glass and rotated by an Alnico magnet mounted outside and below the beaker. A “home-made” apparatus constructed of inexpensive materials for determining copper, nickel, silver, cadmium, and zinc in plating solutions was used by Langford (68). He used base metals for the cathode, as did Kovalenko (56, 60, 61), who employed anodized aluminum as a cathode A number of publications describe instruments for controlling the potential of an electrode during electrolysis. Lamphere has described two instruments (66, 67) for such a purpose, both useful where traces are being separated, but the newer instrument (66) is capable of producing higher currents or voltages up to 250 volt-amperes. Lingane and Jones (77) have built an instrument of this kind, from which unusual stability and good service may be anticipated. The circuit of Chambers (19) permits simultaneous control of several cells. Circuits depending on optical principles for balancing have been constructed by Kovalenko (55, 58) and Thomas (153). Perhaps the narrowest control may be obtained with the circuit developed by Penther and Pompeo (184), for which sensitivity of electrode changes of only 1 mv. is claimed. A multipurpose instrument suitable not only for the control of electrode poteritials but also for electrographic and coulometric electroanalysis and other electrical methods of analysis, has been reported by Lingane (74). Kovalenko (57) has a dual-purpose unit also usable for polarography. -4llen’s (1) apparatus for constant potential cathode reductions is especially designed for use with organic compounds, but may also be used for potential-current curves in concentrations too high for the usual polarographic instruments. Reilley and coworkers (130) describe a simple three-tube constant current source for coulometric analysis, which may also be used as a constant voltage source. Schleicher (136) has devised equipment for internal electrolysis by which 0.2 gram of copper, for example, may be deposited in only 3 or 4 minutes.
though two or three publications in book form have been published. The most comprehensive and the most notable is a section of a monograph by Bottger ( 8 ) ,which is a revision of his earlier publication. It contains an unusually good bibliography and covers, in a critical fashion, the many procedures available in electroanalysis. It is regrettable that 1949, which saw theappearance of this book, also marked the death of Bottger (do), a contributor for many years to this branch of chemistry. The publication of previously classified material from the hlanhattan Project has made it possible for Casto (17) to report on methods of electrolytic separation using the mercury cell, and separation methods for uranium on solid electrodes. Other important electroanalytical investigations are reported in the same volume. A short review article by Ashley (4) attempts in concise form t o summarize the present stateof development of electroanalysis in its many branches. Kew work on the separation of inclusions from steels is prrsented by Klinger and Koch (51). REVIEW ARTICLES
Recent renew iiterature includes a general coverage of electrical methods by Furman (SS), a review of progress in electroanalysis in Germany during the war by Schleicher (137), and a general review of the advantages and disadvantages of electrolytic separations by Ashley (3). Skowronski (249) hae reviewed the history and development of the classical copper determination with the electric current, especially with regard to the assay of copper of high purity. Rogers (131) considers the peculiar difficulties in depositing radioactive elements from extremely dilute solutions in amounts capable of being detected only by their activity. The use t o which controlled graded potentials may be put in electroanalysis, particularly where separations are to be effected, has been reviewed by Lasaieur (69, 70) aFd Lingane ( 7 6 ) . Lingane has concerned himself, in this paper and in a later (76) one, with the use of controlled potentials for coulometry and for separatory procedures with subsequent polarographic analysis. Kovalenko (69) in a study of “combined electrochemical methods” is likewise concerned with these complementary techniques. The application of electrography, internal electrolysis, and mercury cathode separations to methods of metallurgical microchem91
ANALYTICAL C H
92 A substitute for the chemical coulometer of particular use in coulometric analyses is Lingane’s (78) electromechanical integrator built around a ball and disk transmission. New developments in equipment for mercury cathode separations are mentioned below. ELECTRODEPOSITION
Separations. The use of electroanalysis for separations of various types is widely applied ( 3 ) . New directions for development continue to appear. Combinations of known electrical methods of analysis have lately begun to be studied, with the development of interesting possibilities. Kovalenko (54) employed polarographic determinations of lead and cadmium after the separation of large quantities of copper by electrodeposition, and also the polarographic determination of zinc after precipitation of cadmium on an aluminum electrode. The determination of copper by partial precipitation and weighing, completed by polarographic analysis of the remaining electrolyte for undeposited copper and other elements in brass, has been suggested (142). Rhodium may be separated from iridium by controlled potential electrodeposition under conditions described by MacNevin and Tuthill (83, 84),but the deposit of rhodium is contaminated with oxide and cannot be quantitatively determined without first reducing it in hydrogen. Brouns (11) has studied the separation of cadmium and zinc with controlled potentials. Mercury Cathode. An excellent review of the mercury cathode and its applications with 171 literature references has been prepared by Maxwell and Graham (87). Numerous modifications of the mercury cathode cell are designed to give easy separation of electrolyte and amalgam, faster deposition, and other special advantages (5,128,13S, 134, 143). A means of continually renewing the mercury surface was used by Coriou et al. (34),who found it particularly useful for iron/zinc separation, and complete deposition of manganese and other reducible metals. Tsyb (154) separated iron from zinc a t the mercury cathode in ratios as high as 10 to 1, using an elevated temperature. A means of cleaning the mercury for use in the cell is described by Massetti (86). A more elaborate apparatus available commercially for high speed separation of iron from electrolytes has been devised and tested by Center and corn-orkers (18). Conditions for completely depositing mercury, nickel, cobalt, zinc, and iron on mercury have been investigated by Bottger (9). It is not possible to mention all the procedures reported in the literature in which the mercury electrode is used routinely to effect separations. Among those of special interest has been its use on nickel alloys when magnesium is to be determined (96), on a solution of iron perchlorate preparatory to determining aluminum (158), on high temperature alloys preparatory to determining aluminum and titanium colorimetrically ( l 4 8 ) , and on bronzes preparatory to determining aluminum (93, 94). These latter papers by Mills and the paper by Coriou ( 2 4 ) include rate studies on the mercury cathode. Internal Electrolysis. Schleicher (140) is alone among western analysts with his studies of internal electrolysis. These cover new methods for the precipitation of copper, nickel, cobalt, tin, and lead. Musha (100,101) and Machida (82) have continued a series of papers on the application of various amalgams to the separation and determination of a number of elements under varying conditions. Chernikhov (62) and Kovalenko ( 6 6 ) , respectively, have used internal electrolysis for the determination of tin in ore concentrates and in the presence of antimony and zinc. Kovalenko reports that antimony may be determined from the same solution by internal electrolysis. Mitroshina ( 9 6 )employed internal electrolysis to determine small amounts of copper in iron. An improvement in technique claimed by Chernikhov ( 2 1 ) is the replacement of the semipermeable membrane around the anode by a film of collodion. hluraki has studied methods for depositing arsenic (97) and antimony (98) together with copper when analyzing manganese dioxide,
STRY
Coulometric Analysis. Coulometric analysis is the liveliest, most original, and consequently the most interesting aspect of current electroanalysis. Probably the first paper in this field was published in 1919 and development was slow until the last decade. Continuing the earliest developments has been Elema’s (30) study of the determination of 10 to 100 micrograms of ropper by fmt depositing from solution and then measuring the current generated when the copper is redissolved in a cell, as in the pioneer work of Zbinden (161). Kordesch (53)applied a similar technique to the determination of oxygen by measuring the current from an alkaline cell in which oxygen depolarized the carbon electrode. Receiitly roulometric analysis has been extended to the generation of a number of titrating agents within a cell for direct titration-Le., bromine for the titration of mustard gas (144), antimony ( I d ) , &quinolinol (15), and iodine (160); chlorine (31) and iodine (129) for the titration of arsenic; ferrous ion for the titration of cerium ( 2 3 ) and ceric ion for the titration of ferrous ion ( 3 4 ) ; and cuprous (88) ion for the titration of chromate and vanadate ions. Meier and Swift (89) report that an attempt to use dipositive silver ions as an oxidizing agent was unsuccessful. DeFord and coworkers (66-28) have devised means of preparing titrants outside the cell by quantitatively measured electric current, and this technique promises to open a new phase of coulometric analysis. Another technique for determining halides (80) is the use by Lingane of a silver anode upon which the silver halides may be quantitatively deposited in proportion to the current passed. The halides alone, or in any combination but bromine and chlorine, can be individually satisfactorily determined. Of considerable interest in commercial analysis is the determination of manganese, vanadium, and iron simultaneously by reduction at a cathode followed by an indicator electrode. This work is reported by Oelsen and Gobbels (119). The authors also found it possible to follow automatically the titration of sulfuric acid obtained when sulfur in steel was determined by combustion. Because of the war, this work appears to have been done independently of work reported in this country along somewhat related lines. The microtitration of a series of weak organic acids from acetic to valeric has been accomplished in isopropyl alcohol solution by Carson (16). An advantage of the coulometric titration is that carbonate-free base need not be prepared. Coulometric analysis requires accurate measurement of the amount of current passed in a determination. Two coulometers especially adapted to small currents have been devised by Bogan et al. (10) and SyrokomskiI (158). The first, like that of Lingane mentioned above, is mechanical, while the other, based on the electrode reactions of vanadyl ion, is chemical. Craig and Hoffman (25) of the Kational Bureau of Standards have found that the oxalate coulometer rivals the silver coulometer in accuracy. Coulometry may often be applied to elucidate chemical processes. The reduction states of tellurium and selenium ions studied by Lingane and Niedrach (79) were established by these means. Il’in (48, 4 9 ) used current density in an unusual way for the determination of the chromium content of plating baths. With increasing current density a potential break was observed, depending on the ratio of chromium to sulfuric acid if the temperature and cathode material were defined. Whether this phenomenon may be described as coulometric analysis is doubtful; its explanation is not clear and it may be more closely akin to that of polarography. ELECTROSOLUTION
Stripping and Inclusions in Metals. While the earliest methods of electroanalysis were concerned with the precipitation of a material from solution on an electrode, the value of electrical methods for the dissolution of solid electrodes finally came to be realized. One well established industrial use is in determination
V O L U M E 2 4 , NO. 1, J A N U A R Y 1 9 5 2 of the weight and/or thickness of plated coatings (90). Bendix (6) and Buser (IS) have obtained patents on methods for determining the tin in a plated coating by electrolytic dissolution in standard iodine dissolved in hydrochloric acid. The iodine consumed is a measure of the tin dissolved. Saito (135)has compared the electrolytic with the chemical method for tin to the advantage of the former, especially when considerable copper is also present. 411 methods for measuring the thickness of tin coatings are reviewed by Price and Hoare (126). The chemical “jet” method has been combined by Ogarev (120) with the electrolytic for thickness measurements of a number of common electroplated coatings. A change in current may be used to detect penetration of the plating. Francis ( 3 2 ) used a constant current for successfully measuring the thickness of all common platings on steel, and tin, lead, zinc, and chromium on brass or copper. Gentry and Newson (37) also measured chromium plates by electrolysis in dilute sulfuric acid. Some of the work of Klinger (51)in determining nonmetallic inclusions in metals has been mentioned but progress reports of his work have also appeared in the journal literature (52). Henkel(45) reports the electrolytic method is the best of eightmethods for studying oxide inclusions in steel, but Klinger (50) did not find results for ferrous oxide (FeO) as reliable as with the chlorine method. Wada and Ishii (156, 157) have used the electrolytic method for inclusions in carbon steel and pig iron. A method ( 4 7 ) for discriminating and determining cementite and dissolved carbon in heat-treated carbon steels appeared last year. Electrographic Analysis. The continued appearance of general articles relating to the use of electrographic analysis for testing metals (150) and minerals (159) is evidence that the usefulness of this relatively simple and inexpensive technique is still unfamiliar. A patent application ( 1 4 ) has been filed covering rather general use of the method. In 19.50 a symposium of the Bmerican Society for Testing Materials on the rapid identification of metals featured papers on the general use of the method ( 4 6 ) , the identification of metal finishes ( 7 2 ) ,and the examination of plated and protective coatings for porosity ( 3 6 ) . This last application represents a unique use of electrographic anallsis and has been the subject of three other papers by Shaw (145) and Kronstein (63, 64). Specific applications of the technique have been made by Levy ( 7 1 ) to the identification of high-temperature alloys, by Kum6 and others (65) to the detection of alkali salts in filter paper, and by Miller (91) to the detection of copper. Electro-oxidation and Reduction. The direct use of the oxidizing and reducing properties of anodes and cathodes in place of reagent chemicals as steps in a procedure continues to be studied on a limited scale. Murata et al. (99) used an anode to oxidize manganese for use in colorimetry. The cathodic reduction of uranium has been emplo? ed prchminary to titration J\ ith ceric 1011 (29, 151). DETERhIIRATIOhS BY ELEMENTS
Antimony. Xorwitz (108) found that antimony may be successfully determined from an electrolyte containing sulfuric acid, hydrochloric acid, and hydroxylamine hydrochloride without critical temperature and potential control, although copper, cadmium, tin, arsenic, lead, bismuth, and silver interfere. Bismuth. Bismuth may be quantitatively deposited on a copper-plated cathode a t 90” C. from a tartaric acid-hydrofluoric acid electroh te in the presence of tin, according to Goldberg (40). Arsenic, antimony, and copper interfere. Sorwitz (103) determined bismuth after separation from interfering elements by deposition from a hydrazine sulfate-perchloric acid electrolyte. Copper. An unusually interesting history of the assay of copper by electroanalysis has been referred to (149). Shikhvarger ( 1 4 6 )has studied the separation and determination of minute quantities of copper, lead, and zinc obtained from air samples. Kovalenko (56) reports on the use of an oxidized aluminum cathode for determining copper in the presence of small quanti-
93 ties of cadmium. Notvest (118) has received a patent on an apparatus for simultaneously determining copper and lead in a solution stirred with carbon dioxide. Another contribution t o the simultaneous determination of copper and lead from a perchloric acid electrolyte is by Goldberg (%?), who reports a rapid method for analysis of silicon-aluminum bronze alloy. I n the presence of phosphoric acid, lead cannot be determined with copper, according to Norwitz (lor),but he found that excellent separations can be made of copper from tin when both occur in brasses, bronzes, tin-base alloys, and aluminum alloys. He (102) also reports methods for determining copper in aluminum alloys when tin and antimony are both present, again using a phosphoric acid electrolyte, and for determining copper (114) in the presence of small amounts of bismuth or arsenic ( 1 0 6 ) using hydrogen peroxide in the electrolyte. He also reports a method (11s) by which copper and arsenic are completely deposited on the cathode together from a solution containing hydroxylamine hydrochloride, the arsenic being present as an arsenide of copper. Another study on the determination of copper in the presence of tin by the use of hydrofluoric acid is reported by Veitsblit (155). Copper may be deposited electrolytically when silvercopper alloys are analyzed by first separating the silver with ascorbic acid (39) or as chloride (104). I n the latter case the interference of chlorides is prevented by the presence of a few drops of hydrogen peroxide. Norwitz (110) found that silver may be deposited cathodically in a satisfactory weighable form without potential control from an electrolyte containing sodium nitrite and nitric acid. A number of common elements do not interfere. Copper may be deposited from the solution after removal of the nitrite. A procedure for determining copper electrolytically from perchloric-nitric acid solutions has been devised by Norwitz ( 1 1 7 ) . He reports (109) that copper may be separated quantitatively from tin in a strong sufuric acid solution. Bntimony deposits with the copper and must be separately determined (see lead and nickel). Cadmium. Osborn (111) found that more satisfactory deposits of cadmium may be obtained from perchloric or sulfuric acid solutions containing a trace of gelatin. Separations may be effected from zinc or nickel by the procedure described, and the zinc deposited electrolytically after the removal of cadmium. Zivanovi6 (162) used an electrolyte containing gelatin and boric acid for the determination of cadmium by internal electrolysis from a hot solution after the removal of interfering elements present in zinc concentrates by chemical means. Cobalt. Llacer ( 8 2 ) has devised a microprocedure for determining cobalt by controlled potential deposition from solutions containing hydrazine as a depolarizer. Iron. Haenny et al. ( 4 1 ) used a copper cathode on which to collect quantitatively radioactive SQFe. Sorwita (116) studied the deposition of iron from a phosphoric acid electrolyte. Lead. Mention has been made of various lead determinations. Miller and Currie (92) describe a separation procedure for removing small amounts of lead from bronze alloys preparatory to gravimrtric determination as the chromate. Haupt and Albrich (44) found that the anodic determination of small amounts of lead from pure cadmium was unsatisfactory because of contamination with thallous oxide. Korwitz (115) described a procedure for determining small amounts (0.5 to 2.0 mg.) of lead anodically using copper as a cathode depolarizer. He also reports (105) on the determination of amounts of lead as high as 1 gram from a perchloric acid solution. Kovalenko (60) has studied the cathodic deposition of lead in the presence of zinc on his oxidized aluminum electrode, from which it is removed and determined polarographically. Nickel. Silva Fangueiro ( 147) discusses methods for electrolytically determining nickel and copper from plating baths. Selenium and Tellurium. Norwita (111 ) reports a procedure,
ANALYTICAL CHEMISTRY
94 claimed to be more rapid than earlier ones, for the separation of these elements by codeposition with copper. The actual determination is effected chemically. Thallium. Besson ( 7 ) found that satisfactory results can be obtained for thallium by cathodic deposition on a liquid metal cathode but that the anodic determination is not quantitative. Haupt and Albrich (44) found that traces of thallium can be collected from pure cadmium satisfactorily on the anode from an ammoniacal electrolyte. Tin. Lindsey (73) studied the recovery of 0.1 to 0.3 gram of tin from solutions of the stannous and stannic chlorides. Good recoveries are obtained if care is observed in washing the electrodes. Norwitz (112) employed the electrolytic separation of tin in the presence of hydroxylamine hydrochloride and sulfuric acid on redissolved precipitates of metastannic acid and sulfides. Zinc. Patterson (36, 122, 123) found that zinc may be determined electrolytically in zinc-thorium alloys when more than 1yo of zinc is present. LITERATURE CITED
(1) (2) (3) (4)
Allen, M. J., ANAL.CHEM.,22, 804-6 (1950). Ashley, S. E. Q., Ibid., 21, 70-5 (1949). Ibid., 22, 1379-85 (1950). Ashley, S.E. Q., “Interscience Encyclopedia,” Vol. V, pp. 487-
95, New York, Interscience Encyclopedia, 1947. Bane, R. W., Chemist-Analyst, 40, 20-1 (1951). Bendix, G. H., U. S. Patent 2,455,726 (1948). Besson, J., Anal. Chim. Acta, 3, 158-62 (1949). Bottger, K., “Physikalische Methoden der analytischen Chemie,” 2nd Teil, pp. 99-259, Leipzig, Akademische Verlagsgesellschaft, 1949. (9) Bottger, W.,2. anal. Chem., 128, 421-31 (1948). (10) Bogan, S.,Meites, L., Peters, E., and Sturtevant, J. M., J . A m . (5) (6) (7) (8)
Chem. SDC.,73, 1684-7 (1951). (11) Brouns, R. J., Iowa State Coll. J . Sci., 23, 18-19 (1948). (12) Brown, R. .A,, and Swift, E. H., J . Am. Chem. SOC.,71, 2717-19 (1949). (13) Buser, J . S.,U. S. Patent 2,206,026 (1940). (14) Calamari, J. A., U. S. Patent Appl. 737,061; Official Gat., U.S. Pat. Ofice, 625, 1111 (1949). (15) Carson, W. N., Jr., ANAL.CHEM.,22, 1565-8 (1950). (16) Carson, W.N., Jr., and KO, Roy, Ibid., 23, 1019-22 (1951). (17) Casto, C. C., Natl. Nuclear Energy Ser., Div. VIII, 1, Anal. Chem. Manhattan Project, pp. 511-36, New York, McGrawHill Book Co., 1950. (18) Center, E. J., Overbeck, R. C., and Chase, D. L., ANAL.CHEM.. 23,1134-8 (1951). (19) Chambers, F. IT., J . Sci. Instruments, 27, 292-4 (1950). (20) Chem. Eng. News, 27, 3808 (1949). (21) Chernikhov, Yu. A., and Bol’shakova, G. A., Zauodskayu Lab., 14,3-11 (1948). (22) Chernikhov, Yu. A,, and Roshchina, R. S . , Ibid., 14, 383-6 (1948). (23) Cooke, W. D., and Furman, N. H., ANAL.CHEY.,22, 896-9 (1950). (24) Coriou, H., GuBron, J., Hering, H., and LBveque, P., J . chim. phys., 48,55-8 (1951). (25) Craig, D. N., and Hoffman, J. I.,Phys. Rev., 80, 487 (1950). (26) DeFord, D. D., Johns, C. J., and Pitts, J. N., ANAL.CHEM.,23, 9 4 1 4 (1951). (27) DeFord, D. D., Pitta, J. N., and Johns, C. J., Ibid., 23, 938-40 (1951). (28) DeFord: D. D.. Pitts. J. N.. Jr.. and Johns. C. J.. Proc. \ratl. Acad.’Sci. V : S., 36, 612-13 (1950). (29) Dept. Sci. Ind; Research, Chem. Research, 37 (1947). See Brit. Absts. C,” No. 428, 52 (Feb. 1950.) (30) Elema, B., Antonie van Leeuwenhoek, J . Microbial. Serol., Jubilee Vol. Albert J . Kluyuer, 12, 243-56 (1947). (31) Farrington, P. S., and Swift, E. H., ANAL.CHEM.,22, 889-91 (1950). (32) Francis, H. T., J . Electrochem. Soc., 93, 79-83 (1948). (33) Furman, N. H., Record Chem. Progress, 11, 3 3 4 5 (1950). (34) Furman, N. H., Cooke, W. D., and Reilley, C. N., A N ~ L . CHEM.,23, 945-6 (1951). (35) Furman, N. H., and Jensen, K. J., Natl. Nuclear Energy Ser., Div. VIII, 1, Anal. Chem. Manhattan Project, pp. 392-403 (1950). (36) Galitzine, N., and Ashley, S. E. Q., ASTM Symposium on Rapid Methods for Identification of Metals; Spec. Tech. Pub. 98, 61-8 (1949). ~~
I
(37) Gentry, C. H. R., and Kewson. D., Electroplating 1, 759-65 (1948); Bull. Brit. Sci. Instruments Research Assoc., 4, 59 (1949). (38) Goldberg, C., Foundry, 78, 2 3 4 4 0 (1950). (39) Goldberg, C., Metallurgia, 41, 174 (1950). (40) Ibid., 42, 108 (1950). (41) Haenny, G., Jaccottet, A,, and Mayer, R., Helv. Chim. Acta, 32, 1406-14 (1949). (42) Halssinsky, M., J . chim. phys., 43,21-9 (1946). (43) Halssinsky, M., Faraggi, H., Coche, A., and Avignon, P., Phys. Bar., 75, 1963-4 (1949). (44) Haupt, G., and Albrich, A., 2. anal. Chem., 132, 161-4 (1951). (45) Henkel, H., Ibid., 128, 26-41 (1947). (46) Hermance, H. W., and Wadlow, H. V., ASTM Symposium
on Rapid Methods for Identification of Metals; Spec. Tech. Pub. 98, 12-34 (1949). (47) H u t n i k , 17, 19-21 (July-August 1950); J . Iron Steel Inst., 168, 227 (1951). (48) I l k , V. A., EZectrophting, 3, 130-1 (1949). (49) Il’in, V. A,, Zavodskaya Lab., 14, 1389-90 (1948). (50) Klinger, P., Arch. Eisenhtittaw., 20, 151-63 (1949). (51) Klinger, P., and Koch, W., “Beitrage zur metsllkundlichen Analyse,” Daaseldorf, Verlag Stahleisen, 1949. (52) Klinger, P., and Koch, W., Stahl u. Eisen, 68, 321-33 (1948). (53) Kordesch, K., and Marko, A,, Mikrochemie urn. M i b o c h i m . Acta, 36/37, 420-4 (1951). (54) Kovalenko, P. N., Zavodakaya Lah., 14, 386-91 (1948). (55) Ibid., pp, 938-41. (56) Ibid., 15, 915-18 (1949). (57) Ibid., pp. 1308-13. (58) Kovalenko, P. N., Zhur. Anal. Khim., 4, 21-5 (1949). (59) Ibid.. 5 . 217-27 (Julv-Aueust 1950). (60j Kovalenko, P. N:, and Dmitrieva, V . L., Zavodskaya Lab., 16, 548-54 (1950). (61) Kovalenko, P. N., and Dmitrieva, V. L., Zhur. Anat. Khim., 2, 85-92 (1947). (62) Kovalenko. P. N.. and Lektorskaya. N. A.. Zavodskar/a Lab., 15, 1171-6 (1949). (63) Kronstein, M., Chim. peintures, 13, 151-2 (1950). (64) Kronstein, M., Ward, M. M., and Roper, R., I d . EWJ. Chem., 42, 1568-72 (1950). (65) KumB, S., Otozai, K., and WatanabB, H., Yature, 166, 1076-7 (1950). (66) Lamphere, R. W., ANAL.CHEM.,23, 258-60 (1951). (67) Lamphere, R. W., and Rogers, L. B., Ibid., 22, 463-8 (1950). (68) Landord. K. E.. Electrodatina. 3. 443-5. 454 (1950). (69) Lassjeur, A., Chim. anal:, 32, 59-82 (1950). (70) Ibid., pp. 103-8. (71) Levy, LM.E., Iron Age, 164, No. 7, 98-100 (1949). (72) Lewis, A,, and Evans, D. R., ASTM Symposium on Rapid Methods for Identification of Metals: Spec. Tech. Pub. 98. 58-60 (1949), (73) Lindsey, A. J., Analyst, 75, 104-5 (1950). (74) Lingane, J. J., ANAL.CHEY..21, 497-9 (1949). (75) Lingane, J. J., Anal. Chim. ACtcI, 2, 584-601 (1948). (76) Lingane, J. J., Record Chem. Progress, 10, 1-8 (1949). (77) Lingane, J. J., and Jones, s. L., Ah-4~.CHmr,, 22, 1169-72 (1950). (78) Ibid., pp. 1220-1. (79) Lingane, J. J., and Niedrach, L. IT., J . Am. C h a . Soc.. 70, 4115-20 (1948); 71, 196-204 (1949). (80) Lingane, J. J., and Small, L. rl., ANAL.CHEM.,21, 1119-22 (1949). (81) Llacer, A. J., Anales f a r m . bioqulm. (Buenos Aires), 19, 48-55 (1948). (82) Machida, Y., J . Chem. Soc. J a p a n , 67, 100-1 (1946). (83) MacNevin, IT. M., and Tuthill, S.I f . , ANAL.CHEY.,21, 10524 (1949). (84) MacNevin, TV. M., and Tuthill, S. JI., Crucible, 34, 33 (January 1949). (85) Marion, A. P., ANAL.CHEM.,21, 650 (1949). (86) Massetti, P. 9.,Chemist-Analyst, 38, 72 (1949). (87) Maxwell, J. A,, and Graham, R. P., Chem. Revs., 46, 471-98 (1950). (88) Meier, D. J., Myers, R. J., and Swift, E. H., J . Am. Chem. SOC., 71, 2340-4 (1949). (89) Meier, D. J., and Swift, E. H., Ibid., 72, 5331-2 (1950). (90) MetalEoberfltiche, 2, 120-2 (1948). (91) Miller, C. F., Chemist-Analyst, 39, 9 (1950). (92) Miller, C. C., and Currie. L. R., Analyst, 75, 471-3 (1950). (93) Mills, E. C., and Hermon, S.E., Metal I n d . (London), 7 6 , 3 4 3 4 (1950). (94) Ibid., 77, 275-6 (1950). (95) Minster, J. R., Analyst, 71, 74-7 (1946). (96) Mitroshina, A. V., and Tarasova, L. S., Zavoskaua Lab., 16, 874-5 (1950).
V O L U M E 2 4 , NO. 1, J A N U A R Y 1 9 5 2 Muraki, I., and Ishimaru, S.,J . Electrochem. SOC.J a p a n , 19, 46-9 (1951). Ibid., pp. 155-9. Muratrs, Y., Shioda, K , , and Takahashi, R., Ihid.. 10, 450-1 (1942). Musha, S.,J . Chem. SOC.J a p a n , 68, 25 (1947). Musha, A., and Suzuki, Y., Ibid., 68, 24 (1947). Norwitz, G., Am. Foundryman, 18, 27 (1950). Norwitz, G., Analyst, 75, 473-5 (1950). Ibid., pp. 551-2. Ibid., 76, 113-14 (1951). Ihid., PP. 236-7. Norwitz, G., ASAL. CHEX.,21, 523-5 (1949). Ihid., 23, 386-7 (1951). Norwitz, G., A n a l . Chim. d c t a , 4, 53&8 (1950). Ihid., 5 , 106-8 (1951). Ibid., pp. 109-14. Norwitz. G.. 2. anal. Chem.. 131. 266-8 (1950). Ibid., pp. 41’&12. Ibid., pp. 412-13. Ihid., 132, 165-7 (1951). Ihid., pp. 168-70. Norwita, G., and Norwitz, I., Metallurgia, 42, 405 (1950). Notvest, R . W.,U. S. Patent 2,544,802 (1951). Oelsen, W., and Gobbels, P., Stuhl u. Eisen, 69, 33-40 (1949). Ogarev, -4.,J . Applied Chem., U.S.S.R.,19, 311-15 (1946) [English translation Metal I d . , 70, 338-40 (1947)l. Osborn. G. H., Metallurgia, 40, 111-13 (1949). Patterson, J. H., and Banks, C. V., ANAL.CHEM.,20, 897-900 (1948). Patterson, J. H., and Banks, C. V., U. S. Atomic Energy Commission. MDDC-1708 (Dec. 29, 1947). Penther, C. J., and Pompeo, D. J., ANAL.CHEM.,21, 178-80 (1949). Phillips, D. F., Metallurgia, 35, 169-71 (1947). Price, J. IT.,and Hoare, W. E., “Determining the thickness of tin coatings,” Greenford, England, Tin Research Institute (1949). Rabbitta, F. T., Can. Chem. Process Ind., 32, 1023-5 (1948). Rabbitts, F. T., Chem. Canada, 1 , 2 1 (1949). Ramsey, JV. J., Farrington, P. S., and Swift, E. H., ANAL. CHEM.,22, 332-5 (1950). Reilley, C. N., Cooke, W. D., and Furman, N. €I., Ihid., 23, 103G2 (1951). Rogers, L. B., Ihid., 22, 1386-7 (1950). Rogers, L. B., and Stehney, A. F., Atomic Energy Commission, AECD-2239 (1948). I
,
95 (133) Rynesiewioz, J., ANAL.CHEM.,21, 756 (1949). (134) Rynasiewica, J., Atomic Energy Commission, AECD-2240 (1948). (135) Saito, J., J. Electrocha. Assoc. Japan, 10, 445-9 (1942). (136) Schleicher, A., Chm.-Ing.-Tech., 22, 11-12 (1950). (137) Schleicher, A., “Naturforschung und Medizin in Deutschland 1939-1946,” Bd. 29, Analytische Chemie, pp. 49-54, \Viesbaden, Dieterich’sche Verlagsbuchhandlung,, 1948. (138) Schleicher, A., 2. anaE. Chem., 128, 381-92 (1948). (139) Ibid., 133, 135-43 (1951). (140) Schleicher, A., Z . Erzbergbau u. Metallhzittenw., 2, 210-12 (1949). (141) Schleicher, A,, and Schlosser, O., 2. anal. Chem., 130, 1-16 (1949). (142) “Scientific Apparatus and Methods,” summer ed., pp. 2-5, Chicago, E. H. Sargent and Co., Section 1, 1948. (143) Ibid., winter ed., pp. 3-5, Section 1, 1948-49. (144) Shaffer, P. A., Jr., Briglio, A., Jr., and Brockman, J. A , , Jr., ANAL.CHEM.,20, 1008-14 (1948). (145) Shaw, W. E., and Moore, E. T., Ihid., 19, 777-9 (1947). (146) Shikhvarger, F. D., Zavodskaya Lab., 15, 1165-71 (1949). (147) Silva Fangueiro, N. da, Engenharia e quim. (Rdo de J a n e r h ) , 2, NO.3, 15-16 (1950.) (148) Silverman, L., Chemiat-Analyst, 37, 62-4 (1948). (149) Skowronaki, S., A S T M BUZZ.,KO. 174, 60-5 (May 1951). (150) Steel, 126, 56-60, 76 (Jan. 23, 1950). (151) Sutton, J., Natl. Research Council Canada, Atomic Energy Project Div., Research (1945), N.R.C. 1591. (152) Syrokomskil, V. S., and Nazarova, T. I., J. Anal. Chem. U.S.S.R., 6, 15-23 (1951). (153) Thomas, E. B., and Nook. R. J., J . Chem. Education, 27, 217-19 (1950). (154) Tsyb, P. P., and KozlovskiI, M. T., Z a v o d s k a y a h b . , 16,147-150 (1950). (155) Veitsblit, G. I., Ihid., 13, 1255 (1947). (156) Wads, I., and IshiI, R., Repts. Sci. Research Inst. ( J a p a n ) , 24, 3 2 2 4 (1948). (157) Ibid., 25, 211-13 (1949). (158) Wiberley, 5. E., and Bassett, L. G., ANAL.CHEM., 21, 609-12 (1949). (159) Williams, D., and Narchla, F. M., Bull. Inst. M i n i n g Met., No. 533, 257-95 (1951). (160) Wooster, W. S., Farrington, P. S.,and Swift, E. H., ANAL. CHEM.,21, 1457-60 (1949). (161) Zbinden, C., Bull. soc. chim. b i d , 13, 35-40 (1931). (162) ZivanoviO, D., Bull. doc. chim. Belgrade, 14, 273-80 (1949). RECEIVED November 26. 1951.
Inorganic Gravimetric Analysis F. E. BEAMISH AND W. A. E. MCBRYDE University of Toronto, Toronto, Canada
LRING the period under review (June 1950 to June 1951) significant contributions in the field of gravimetric analysis have come from three foreign laboratories. At the Institute of Obslichei, Pshenitsyn and coworkers recorded the results of an extensive lnvestigation of determination of platinum metals. At the Sorbonne, Dupuis, Duval, and coworkers contributed considerable data dealing with safe ignition temperatures of precipitates Rao and coq-orkers at Andhra University have materially increased the literature dealing with the determination of the earth elements of column four. The number of organic precipitants used in inorganic analysis continues to increase; however, there has been relatively little progress in establishing relationships between structure and efficiency as a precipitating reagent. Out of such investigations might come many much needed specific reagents. GENER4L PROCEDURES
Preparation of Samples and Precipitates. An automatic pipetype sampler, suitable for coal, ores, fertilizers, etc., was discussed b y J‘isman (176). Westwood (186) recorded precautions t o be taken during sampling of pig iron and cast iron. The low temperature decomposition of various corrosion-resisting materials
was discussed b y Seelye and Rafter (169) and Rafter (150) Effective decomposition and more easily dissolved products were obtained b y heating with sodium peroxide at 480” & 20”. Iridosmine required four treatments. Except in the case of sulfide, the platinum crucible was not attacked. By fusing with sodium carbonate and sulfur Sarudi (158) converted arsenic, antimony, and tin into water-soluble products. Some copper passed into the aqueous extract, and if large amounts of arEenic mere present there was some loss by volatilization. Martinez (116) stated that calcinations of the hydrates of iron and aluminum oxides could be replaced by infrared desiccation, although empirical factors were required to obtain the weights of metal, and the precision was poor. Lead dishes Rere used by Fainberg and Iiedrova (50) in determining tin in poor ores and tailings. Proskuryakova (136) discussed accelerated filtrations of solutions containing silica. At p H less than 4 stable and easily filtered solutions were obtained. Methods of Selective Separations and General Gravimetric Reagents. GalmBs and hlataix (70) measured the p H at which the sulfides of cadmium, zinc, cobalt, and nickel could be precipitated. Zinc and cadmium were separated quantitatively a t p H of 0.4. Acridine in dilute acetic acid was used by Fidler (54) for the gravimetric estimation of vanadates, chromates, molybdates, and
