This standard specifies the determination method of solvent extracts in papermaking raw materials. This standard is applicable to various papermaking plant fiber raw materials. GB/T 2677.6-1994 Determination of organic solvent extracts in papermaking raw materials GB/T2677.6-1994 Standard download decompression password: www.bzxz.net

National Standard of the People's Republic of China
Fibrous raw material-Determination ofsolvent extractives
1 Subject content and scope of application
This standard specifies the determination method of solvent extractives in papermaking raw materials. This standard is applicable to various papermaking plant fiber raw materials. 2 Reference standards
GB/T2677.1 Sampling of samples for analysis of papermaking raw materials GB/T2677.2 Determination of moisture content of papermaking raw materials 3 Principle
GB/T 2677.6—94
GB 2677. 6—81
GB 2677. 7--81
The determination method is to extract the sample with an organic solvent, then evaporate and dry the extract, and weigh it, so as to quantitatively determine the content of the substance extracted by the solvent. Www.bzxZ.net
Ether can extract resin, wax, fat, etc. contained in the raw materials, while benzene alcohol can not only extract resin, wax and fat contained in the raw materials, but also extract some ether insoluble substances, such as tannin and pigment. 4 Instruments and blood
4.1 General laboratory instruments.
4.2 Soxhlet extractor with a capacity of 150mL.
4.3 Constant temperature water bath.
4.4 Drying oven.
4.5 Weighing bottle.
4.6 1/10,000 balance.
5 Reagents
Analytically pure reagents should be used during analysis.
5. 1 Ether (HG3—1002)(CH;CH2), 0. 5.2 Benzene (GB 690) C, H6.
5. 3 Ethanol (GB 679) CH:CH2OH:95%(m/m). 5.4 Benzene-ethanol mixture: 2:1(V/V). Mix 2 volumes of benzene and 1 volume of 95% ethanol evenly for use. Approved by the State Administration of Technical Supervision on September 24, 1994 210
Implementation on March 1, 1995
6 Sampling
Perform in accordance with the provisions of GB/T2677.1.
7 Test steps
GB/T 2677.6—94
7.1 Safety measures: The organic solvents used in the entire experiment are flammable and toxic, so the experiment should be carried out in a fume hood. 7.2 Accurately weigh 3 ± 0.2g (weighed to 0.0001g) of the prepared sample (at the same time, weigh another sample to determine the moisture content according to GB/T2677.2), wrap it with qualitative filter paper that has been extracted with the required organic solvent (5.1 or 5.4, depending on the measurement requirements) for 1~~2h, tie it with a thread, do not wrap it too tightly, but also prevent it from being too loose to avoid leakage. Put it into the Soxhlet extractor, add no less than 150mL of the required organic solvent to exceed its overflow level, and add about 20mL more, install the condenser, connect the extraction instrument, and place it in a water bath. Turn on the cooling water, adjust the heater so that the boiling rate of the organic solvent is no less than 4 times per hour in the Soxhlet extractor, and extract for 6h. After the extraction is completed, lift the condenser. If paper wool is found in the extract, the extract should be filtered into the weighing bottle through the filter paper, and then rinse the bottom bottle and filter paper with a small amount of organic solvent in batches. Carefully remove the paper bag containing the sample from the extractor with a clamp, then reconnect the condenser to the extractor and evaporate until the extract in the bottom bottle is about 30mL, so as to recover part of the organic solvent. Remove the bottom bottle, wipe it clean, place it in an oven at 105±2℃ for 5h and weigh it, or remove the bottom bottle, move its contents into a weighing bottle that has been dried to a constant weight, and rinse the bottom bottle with a small amount of organic solvent for extraction 3 to 4 times. The washing liquid should also be poured into the weighing bottle, place the weighing bottle in a water bath, and carefully heat it to evaporate the excess solvent. Finally, wipe the outside of the weighing bottle clean and place it in an oven, bake it at 105±2℃ for 5h and weigh it. 8 Result calculation
The organic solvent extract content X (%) is calculated as follows: (mi-mo)100
m2(100-w)
Where: m. —The mass of the empty weighing bottle or extraction bottom bottle, g, m1-The mass of the extract after drying the weighing bottle or extraction bottom bottle, g, m2——The mass of the air-dried sample, g;
W—The moisture content of a sample,%.
Carry out parallel determinations at the same time, and take the arithmetic mean as the determination result. It is required to be accurate to the second decimal place, and the difference between the calculated values ​​of two determinations should not exceed 0.20%.
9 Test report
The test report should include the following items:
This standard number;
All information required for identifying the sample,
The extraction solvent used,
Any operation that deviates from this standard.
Additional remarks:
This standard is proposed by China Light Industry General Association.
GB/T2677.6-94
This standard is under the jurisdiction of the National Technical Committee for Standardization of Paper Industry. This standard was drafted by the Paper Industry Research Institute of the Ministry of Light Industry. The main drafters of this standard are Wei Pengyue and Yang Yanfei. This standard refers to the American Pulp and Paper Association standard TAPPIT204om-88 "Organic Solvent Extracts of Wood and Pulp".
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