1、BRITISH STANDARD BS1428-B2: 1960 Specification for Ammonia distillation apparatus (Markham) Microchemical apparatus Group B: apparatus for the determination of elements by other than combustion methodsBS1428-B2:1960 This BritishStandard, having been approved by the ScientificGlassware and RelatedLab
2、oratory ApparatusIndustry StandardsCommittee and endorsed by the Chairman oftheChemical Divisional Council, was published undertheauthority of the GeneralCouncil on 29February1960 BSI12-1999 First published December1953 First revision February1960 The following BSI references relate to the work on t
3、his standard: Committee references LBC/11 andLBC/11/1 Draft for comment CZ (LBC)5632 ISBN 0 580 34147 X Co-operating organizations The Scientific Glassware and Related Laboratory Apparatus Industry Standards Committee, under whose supervision this BritishStandard was prepared, consists of representa
4、tives from the following Government departments and scientific and industrial organizations: Admiralty* Air Ministry Association of British Chemical Manufacturers* Association of Scientific Workers Board of Trade British Association for the Advancement of Science British Chemical Ware Manufacturers
5、Association* British Laboratory Ware Association* British Lampblown Scientific Glassware Manufacturers Association* British Pharmacopoeia Commission British Scientific Instrument Research Association* Chemical Society* D.S.I.R.Laboratory of the Government Chemist* D.S.I.R.National Chemical Laborator
6、y* Glass Manufacturers Federation* Institute of Petroleum Ministry of Aviation* Ministry of Health National Physical Laboratory (D.S.I.R.)* Oil Companies Materials Association Pharmaceutical Society of Great Britain* Royal Institute of Chemistry* Science Masters Association Society for Analytical Ch
7、emistry* Society of Chemical Industry* Society of Glass Technology* Standardization of Tar Products Tests Committee The Government departments and scientific and industrial organizations marked with an asterisk in the above list, together with the following, were directly represented on the committe
8、e entrusted with the preparation of this standard: Association of Clinical Pathologists British Rubber Producers Research Association Medical Research Council Physiological Society War Office Individual Manufacturers Amendments issued since publication Amd. No. Date CommentsBS1428-B2:1960 BSI 12-199
9、9 i Contents Page Co-operating organizations Inside front cover Foreword ii 1 Scope 1 2 Material 1 3 Design and dimensions 1 4 Alternative apparatus with ground joint 1 Appendix A Notes on method of use 2 Appendix B 4 Figure 1 Markham ammonia distillation apparatus 3BS1428-B2:1960 ii BSI 12-1999 For
10、eword This standard makes reference to the following BritishStandards: BS1428-A2, Nitrogen combustion train (micro-Dumas). BS1428-B1, Nitrogen determination apparatus (micro-Kjeldahl). BS1848, Glass condensers. BS2761, Spherical ground glass joints. This standard, which was first published in1953, i
11、s one of a series of Parts of BS1428 “Microchemical Apparatus”, (see list in Appendix B). The only substantial changes in the present revision are that the design of the condenser is now that specified in BS1848 1)and that the alternative, jointed apparatus now employs only the spherical joint intro
12、duced by amendment in1956, the conical joint previously permitted having been deleted. PartB2 specifies an ammonia distillation apparatus of the type described by Markham 2) , which has been found especially useful for biochemical work. It has disadvantages if the quantity of distillant used exceeds
13、25ml, and in this case more satisfactory results may be obtained by the addition of a splash-head, of the type specified in BS1428- B1 3) , between the distillation vessel and the condenser. While only the apparatus is specified in this and other parts of BS1428, it must be made clear that satisfact
14、ory results will not be obtained without careful attention to the procedure in carrying out the determination, and that this requires both training and experience in microchemical work. Notes on the method of use of the apparatus are given for guidance in Appendix A, but these are not intended to be
15、 either mandatory or comprehensive. Apparatus for the micro-determination of nitrogen is specified also in BS1428-A2 4)and BS1428-B1 3) A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application.
16、 Compliance with a British Standard does not of itself confer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, pagesi andii, pages1 to4 and a back cover. This standard has been updated (see copyright date) and may have had amendments inc
17、orporated. This will be indicated in the amendment table on the inside front cover. 1) BS1848, “Glass condensers”. 2) R. MARKHAM, Biochem. J.,36,1942,790. 3) BS1428-B1, “Nitrogen determination apparatus (micro-Kjeldahl)”. 4) BS1428-A2, “Nitrogen combustion train (micro-Dumas)”.BS1428-B2:1960 BSI 12-
18、1999 1 1 Scope This BritishStandard specifies steam-jacketed distillation apparatus of the Markham type for the micro-determination of nitrogen by the Kjeldahl method. 2 Material The apparatus shall be constructed throughout of borosilicate glass, as free as possible from visible defects, and shall
19、be well annealed. 3 Design and dimensions The apparatus shall conform to the general design shown in Figure 1 and shall comply with the mandatory dimensions, which are underlined in the figure. Dimensions not underlined in the figure are recommended. The connection between the filling funnel and the
20、 main body, and also the glass tubing between the distillation vessel and the condenser, shall be robust. 4 Alternative apparatus with ground joint As an alternative to the one-piece apparatus illustrated in Figure 1, an interchangeable spherical ground glass joint, size18/9 BS, complying with BS276
21、1 5)may be inserted between the distillation vessel and the condenser. The ball is fitted to the vertical portion of the outlet tube of the distillation vessel and the cup to the top of the condenser. 5) BS2761, “Spherical ground glass joints”.BS1428-B2:1960 2 BSI 12-1999 Appendix A Notes on method
22、of use Transfer the digested sample to the distillation vessel through the funnel and pass steam through the jacket, leaving the drainage tube open, until the apparatus is sufficiently warm for condensation not to occur. Add excess alkali (and a reagent to decompose mercury-ammonia complexes if merc
23、ury has been used in the digestion) and close the rubber tubing on the drainage tube with a spring clip so that steam passes into the distillation vessel, thus sweeping ammonia through the condenser. Continue the steam distillation under carefully controlled conditions until all the ammonia has been
24、 absorbed in a suitable solution in a conical flask and determine it by any suitable method. After the distillation is complete, cut off the supply of steam so that the contents of the distillation vessel are sucked into the main body of the apparatus. Wash out and empty the distillation vessel by t
25、he same method ready for the next distillation.BS 1428-B2:1960 BSI 12-1999 3 All dimensions are in millimetres. Dimensions underlined are mandatory, others are recommended. Figure 1 Markham ammonia distillation apparatusBS1428-B2:1960 4 BSI 12-1999 Appendix B Parts of BS1428, “Microchemical apparatu
26、s” Group A. Combustion trains for the determination of elements. Part A1: Carbon and hydrogen combustion train (Pregl type); Part A2: Nitrogen combustion train (micro-Dumas); Part A3: Halogens and sulphur combustion train (Pregl); Part A4: Halogens and sulphur combustion train (micro-Grote); Part A5
27、: Rapid method combustion tubes (Belcher and Ingram type). Group B. Apparatus for the determination of elements by other than combustion methods. Part B1: Nitrogen determination apparatus (micro-Kjeldahl); Part B2: Ammonia distillation apparatus (Markham). Group C. Apparatus for the determination of
28、 organic groups. Part C1: Alkoxyl and alkylimino group determination apparatus; Part C2: Acetyl group determination apparatus (Wiesenberger). Group D. Volumetric apparatus. Part D1: Burettes with pressure-filling device and automatic zero; Part D2: Washout pipettes; Part D3: Micro-nitrometer (Pregl
29、type); Part D4: Capillary pipettes; Part D5: Syringe pattern micro-pipette; Part D6: Micrometer-operated burette. Group E. General accessory apparatus. Part E1: Crucibles for microchemical analysis; Part E2: Micro-beakers; Part E3: Micro-centrifuge accessories. Group F. Filtration accessories. Part
30、F1: Filtration apparatus for microchemical analysis. Group G. Heating, cooling and drying accessories. Part G1: Heating and cooling blocks for microchemical purposes; Part G2: Vacuum drying ovens for microchemical purposes. Group H. Weighing accessories. Part H1: Weighing vessels for microchemical a
31、nalysis. Group I. Combustion accessories. Part I1: Combustion boats and sheath for microchemical analysis. Group J. Electrolytic accessories. Part J1: Micro-electrolytic apparatus. Group K. Apparatus for physical methods. Part K1: Vaporimetric molecular weight apparatus. Group L. Extraction accessor
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