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1、International Standard 697 INTERNATIONAL ORGANIZATION FOR STANDARDIZATION.MEYHAPOHAR OPrAHHBAL,kIR IlO CTAHAAPTM3AWlti*ORGANlSATlON INTERNATIONALE DE NORMALISATION Surface active agents - Washing powders - Determination of apparent density - Method by measuring the mass of a given volume Agents de s
2、urface - Poudres B laver - D, 0 (7 *., L$q UDC 661.185 : 531.755.2 Ref. No. IS0 697-1981 (E) iii f Descriptors : surfactants, washing powders, tests, determination, bulk density. Is s Price based on 3 pages Foreword IS0 (the international Organization for Standardization) is a worldwide federation o
3、f national standards institutes (IS0 member bodies). The work of developing Inter- national Standards is carried out through IS0 technical committees. Every member body interested in a subject for which a technical committee has been set up has the right to be represented on that committee. Internat
4、ional organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. Draft International Standards adopted by the technical committees are circulated to the member bodies for approval before their acceptance as International Standards by the IS0 Council. Internati
5、onal Standard IS0 697 was developed by Technical Committee ISO/TC 91, Surface active agents, and was circulated to the member bodies in March 1980. It has been approved by the member bodies of the following countries : Australia Hungary Austria India Belgium Italy China Japan Egypt, Arab Rep. of Kor
6、ea, Rep. of France Netherlands Germany, F. R. Poland Romania South Africa, Rep. of Spain Switzerland USSR No member body expressed disapproval of the document. This International Standard has also been approved by the International Union of Pure and Applied Chemistry (IUPAC). This second edition can
7、cels and replaces the first edition (i.e. IS0 697-1975). 0 International Organization for Standardization, 1981 0 Printed in Switzerland -,-,- INTERNATIONAL STANDARD IS0 697-1981 (E) Surface active agents - Washing powders - Determination of apparent density - Method by measuring the mass of a given
8、 volume 0 Introduction The apparent density of a powder can be evaluated either by measuring the mass which occupies a given volume, or by measuring the volume occupied by a given mass. In both cases, the procedure involves transfer of the powder from its original container to that used for the meas
9、urement. Owing to the friability of the product, to its flow or caking properties, to the varying geometry of particles of which it is composed, and to the unavoidable compaction resulting from pouring into the container for measurement, the apparent density determined will generally differ from tha
10、t of the product in its original con- tainer or package. The result of the determination, therefore, gives only a conven- tional value related to the method used. 1 Scope This International Standard specifies a method for the deter- mination of the apparent density of washing powders by measuring th
11、e mass of a given volume. 2 Field of application The method is applicable to free flowing powders and, pro- vided that an appropriate funnel is used, to powders which have a tendency to cake. The method is suitable for other substances in the form of powder or granules. In the case of powder contain
12、ing lumps, the method is ap- plicable only if these can be disintegrated readily without break- ing down the particles of the powder. 3 References IS0 607, Surface active agents and detergents - Methods of sample division. IS0 3424, Sodium perborates for industrial use - Determina- tion of bulk dens
13、ity. 4 Definition ) apparent density : The mass, in grams, of powder which oc- cupies a volume of one millilitre under standardized conditions. 5 Principle Determination of the mass of powder in a receiver of known dimensions, after filling with the sample from a funnel of specified shape under spec
14、ified conditions. 6 Apparatus 6.1 Funnel, made of stainless steel, plastics, wood or other suitable material. All surfaces in contact with the flowing powder shall be smooth and polished and shall not permit a build up of an electrostatic charge by the flow of the powder. The internal diameter of th
15、e orifice shall be 40 mm for use with free flowing powders and 60 mm for use with powders show- ing a tendency to cake. 6.2 Receiver, of capacity 500 ml, constructed of materials similar to those of the funnel. The receiver shall be calibrated as described in 8.1 and the volume may, for convenience,
16、 be adjusted to 500 III 0,5 ml by machining the rim. 6.3 Stand, capable of holding the funnel and the receiver in fixed positions relative to each other. The funnel shall be held by locating pins passing through holes in the flange of the funnel and the top plate of the stand. The receiver shall be
17、located centrally beneath the funnel by locating studs or other suitable means. The stand may incorporate, if desired, a mechanism for mechanical operation of the closure plate. 1) The gram per millilitre (g/ml) is the unit of density of the CGS system. The unit of density of the International Syste
18、m of Units (SI) is the kilogram per cubic metre (kg/m? : 1 kg/ma = 10-s g/ml. 1 IS0 697-1981 (E) 6.4 Closure plate, 110 mm x 70 mm. Cover the bottom opening of the funnel by means of the closure plate (6.41, holding the plate lightly against the funnel. This apparatus (see the figure) is identical w
19、ith that described in IS0 3424, except for the 60 mm orifice funnel the other dimen- sions of which are : superior diameter 112 mm and height 100 mm. Fill the funnel with the sample up to its top rim, then quickly remove the closure plate, thus allowing the contents of the funnel to run into, and ov
20、erflow from, the receiver. Remove the receiver and place it on a level surface. Carefully level the powder surface by means of the straightedge (6.5) and clean the outside wall with a dry cloth. Weigh the receiver and its contents to the nearest 0,l g. 6.5 Straightedge, of length approximately 150 m
21、m. 6.6 Glass plate, 100 mm x 100 mm x 7 mm. Carry out at least two determinations on different portions of the laboratory sample. 7 Sampling The laboratory sample of washing powder shall be prepared and stored in accordance with IS0 607. 9 Expression of results 9.1 Method of calculation 8 Procedure
22、The apparent density of the powder, in grams per millilitre, is given by the formula 8.1 Calibration of the receiver Calibrate the receiver (6.1) by establishing its volume in the following manner. m 3 - ma V Weigh, to the nearest 0,l g, the clean, empty receiver and place it on a horizontal surface
23、. Fill it with recently boiled distilled water at 20 OC, and remove any bubbles, which collect during the filling, by gently tapping the walls. Place the weighed glass plate (6.6) horizontally against the edge of the upper rim of the receiver. Gently slide the plate across the water surface and, whe
24、n it is nearly across, add 1 to 2 ml of distilled water to the receiver and completely cover the receiver with the plate. Dry the exposed underside of the plate and the sides of the receiver with filter paper and weigh to the nearest 0,l g. where m. is the mass, in grams, of the empty receiver; m3 i
25、s the mass, in grams, of the receiver and its contents; V is the volume, in millilitres, of the receiver. Take, as the result, the arithmetic mean of the two determina- tions provided that the requirement for repeatability (see 9.2) is satisfied. The volume, in millilitres, of the receiver is given
26、by the formula If it is not, repeat the determination m2 - (m. + ml) Express the result to three significant figures as follows : where “Apparent density . . . g/ml”. m. is the mass, in grams, of the empty receiver; 9.2 Repeatability The difference between the results of the two determinations, carr
27、ied out in rapid succession by the same analyst, shall not exceed 5 % of the mean value. ml is the mass, in grams, of the glass plate; m2 is the mass, in grams, of the receiver full of water with the glass plate in position. 8.2 Preparation of test sample 10 Test report Break down any lumps present
28、in the laboratory sample by shaking and rotating the container. The test report shall include the following particulars : Take care to avoid breaking down the particles of powder. a) all details required for complete identification of the sample; Render the laboratory sample homogeneous and reduce i
29、t by means of a conical divider as described in IS0 607. b) whether or not lumps were present in thelaboratory sample; 8.3 Determination cl the reference of the method used; Place the funnel (6.1) on the stand (6.3). Place the tared receiver (6.2) in position. d) type of funnel used (orifice 40 or 6
30、0 mm); 2 ISO697-1981(E) e) the results and the method of expression used; f) any unusual features noted during the determination; orifice I g) any operations not included in this International Stan- dard, or regarded as optional. Dimensions in millimetres Circular flange Circular flange oarallel to the -, I i- t pins - fi - 220 / Locating studs _ Closure plate 110x 70 _ Cylindrical receiver 3 main bolts - (the third is not shown) Figure - Apparatus for determination of apparent density of powders or granules 3 -,-,-