GB/T 2562-1981 Determination of benzene insoluble matter in montan wax

GB/T 2562-1981 Determination of benzene insoluble matter in montan wax GB/T2562-1981 Standard download decompression password: www.bzxz.net

National Standard of the People's Republic of China
Determination of benzene insoluble matter in montan wax
This method is applicable to the determination of benzene insoluble matter in montan wax. GB 2562-81
Method Key Points: Place the wax sample in a filter paper tube, then place the filter paper tube in an extractor, heat and extract with benzene on a water bath, take out the filter paper tube, and dry it to constant weight. Calculate the weight percentage of benzene insoluble matter from the weight of the residue in the filter paper tube. 1. Instruments and reagents
(1) Erlenmeyer flask extractor (see figure) - consists of the following parts: ground-mouth conical flask: 500 ml;
spherical condenser: the end of the conical flask is ground to match the conical flask, and the lower end of the condenser has two symmetrical small holes for hooking; filter paper stick: 20 mm in diameter and 80 mm in height; metal hook;
(2) electric constant temperature water bath: constant temperature range 37-100℃; (3) electric drying oven: can maintain a temperature of 100-110℃; (4) measuring cylinder: 100 ml;
(5) infrared lamp;
(6) dryer;
(7) tall weighing bottle with ground-mouth cover: 28 mm in diameter and 95 mm in height; (8) analytical balance: accurate to 0.0002 g. 2. Reagents and materials
(1) Benzene: analytical grade (GB690-77); (2) square medium-speed qualitative filter paper (GB1915--80). II. Determination steps
3. Place the filter paper tube into a high-type weighing bottle, dry it in a drying oven at 102-105℃ for 1 hour, cover it with a ground-mouth lid, take it out and place it in a desiccator, cover it tightly, and weigh it after cooling for 30 minutes (accurate to 0.0002 grams). Dry, cool and weigh it for another half an hour until the difference between consecutive weighings is no more than 0.0005 grams. 4. Accurately weigh 5 grams of wax sample less than 1 mm (accurate to 0.0002 grams) and put it into a filter paper tube that has been weighed to a constant weight. Add 100 ml of benzene to the extractor and extract it in a 90℃ water bath for more than two hours (note that the filter paper tube cannot come into contact with the benzene liquid in the conical flask) until colorless benzene drips out of the filter paper tube.
5. After the residual benzene in the filter paper tube is drained, take out the filter paper and put it in a high weighing bottle, and pre-dry it under an infrared lamp. Then put it in a drying oven and dry it at 102-105℃ for 1 hour, take it out and put it in a dryer to cool for 30 minutes before weighing (accurate to 0.0002 grams). Dry, cool and weigh for another half an hour until the difference between consecutive weighings is no more than 0.0005 grams. Issued by the General Administration of Standards of the People's Republic of China
The Ministry of Coal Industry of the People's Republic of China proposed to implement it on October 1, 1981
Shanxi Coal Chemistry Institute of the Chinese Academy of Sciences
Beijing Coal Chemistry Institute of Coal Science Research Institute
GB 2562-81
III. Calculation of results
6. Benzene insoluble matter is expressed as a percentage by weight and is calculated as follows: Gt-G2
Benzene insoluble matter=
Wherein: G1—the sum of the weights of the high-type weighing bottle, filter paper and insoluble matter, g; G2—the sum of the weights of the high-type weighing bottle and filter paper, g; G
weight of wax sample, g.
7. Take the arithmetic mean of the results of two parallel determinations as the result of the determination, and take the result to two decimal places. IV. Filling
8. The difference between parallel determinations shall not exceed the following provisions: Fill
(absolute)
Condenser
Metal hook
Filter paper
Triangular flask
Triangular flask extractor
GB256281wwW.bzxz.Net
Simple method for homemade extraction filter paper
Cut a large sheet of qualitative filter paper into 75×75 mm squares and 50×50 mm squares, soak them with distilled water, stick them on a clean glass plate, and gently rub the filter paper hair on the four sides with your fingers. First wrap the large square filter paper on the outer wall of a glass tube with a diameter of 16 mm, and then wrap the small square filter paper on the bottom of the glass tube (there is a small hole at the bottom of the tube). Wrap the two alternately, with 3 layers on the tube wall and 3 layers on the bottom of the tube. Then remove it and dry it in a drying oven at 105℃. 705
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