Water standard provisions r Determination of carbon dioxide content by gravimetric method This standard applies to the determination of carbon dioxide content in manganese ore Determination range: 0.10%-18.00% GB/T 14949.11-1994 Chemical analysis method for manganese ore Determination of carbon dioxide content GB/T14949.11-1994 Standard download decompression password: www.bzxz.net

National Standard of the People's Republic of China
Chemical analysis method of manganese ore
Determination of carbon dioxide content
Manganese ores-Determination of carbon dioxide contentGB/T 14949. 11 --- 94
This standard is equivalent to IS0314-1981 "Determination of carbon dioxide content in manganese ore-gravimetric method". 1 Subject content and scope of application
This standard specifies the determination of carbon dioxide content by gravimetric method. This standard is applicable to the determination of carbon dioxide content in manganese ore. Determination range: 0.10%~18.00%. 2 Method summary
The sample is decomposed with phosphoric acid, oxygen is used as carrier gas, and carbon dioxide is absorbed by alkaline asbestos. Determination is made by gravimetric method. 3 ReagentsWww.bzxZ.net
3.1 Chromium oxide.
3.2 Anhydrous copper sulfate: Prepared by drying crystalline copper sulfate (CuSO,,5H2O) at 180~200C for more than 3h. 3.3 Anhydrous magnesium perchlorate: Dry at 120-150℃ before loading into the absorption tube. 3.4 Alkaline asbestos.
3.5 Sulfuric acid (pl.81 g/ml).
3.6 Phosphoric acid (pl.70g/mL).
Instrument and device
See the figure for the analytical device.
Approved by the State Administration of Technical Supervision on January 18, 1994 and implemented on October 1, 1994
GB/T14949.11-94
A Electric heating plate (with voltage regulator); B: 150mL conical flask C- three-way dropping bottle; I) condenser (straight tube type, water-cooled part 260mm long); E, L- drying tube filled with sulfuric acid (3.5). The sulfuric acid liquid level is about 1cm above the air inlet: F absorption tube filled with chromium oxide (3.1); G absorption tube filled with anhydrous copper sulfate: H- absorption tube filled with anhydrous magnesium perchlorate: J, K- absorption tubes filled with 3/4 alkali asbestos (3.4) and 1/4 anhydrous magnesium perchlorate (3.3) (the weight of each absorption tube does not exceed 40g) Note: A small amount of glass wool is filled on the reagents in all U-shaped tubes. 5 Sample
The sample should pass through a 0.100mm sieve and be air-dried under laboratory conditions. 6 Analysis steps
6.1 Sample quantity
Weigh the sample quantity according to Table 1, accurate to 0.0001 liter, and place it in a dried conical flask. Table 1
Carbon dioxide quantity, %
Sample quantity
0.1～0.5
Weigh the sample at the same time as the determination, and determine the mass percentage of wet water (A). When calculating the carbon dioxide amount result, the result (mass percentage) should be multiplied by the conversion factor K, which is the mass percentage of the carbon dioxide amount determined in the completely dry sample. Conversion factor K
6.2 Blank test
Carry out a blank test with the sample.
6.3 Determination
6.3.1 Connect the device according to the diagram. Connect the cooling water (D). Pass oxygen to check the tightness of the entire system. When it is confirmed that there is no leakage, adjust the oxygen flow rate so that the bubbles in the drying tube (L) at the outlet of the system can be counted. Disconnect and weigh the absorption tubes (J) and (K) every 10 minutes until the weight is constant. Stop passing oxygen. Remove the conical flask (B) containing the sample. Connect the constant-weight absorption tube to the system.
6.3.2 Add 1 to 2 ml of water to the conical flask (B) containing the sample and connect it to the system, and unscrew the air line. Immediately add 15ml of phosphoric acid (3.6) from the acid dropper funnel S.
GB/T14949.1194
(C) to the conical flask (B). The speed of acid addition controls the carbon dioxide to pass through the T drying tube (E) at a rate of 3~4 bubbles/s. When the carbon dioxide content in the sample is less than 5%, the phosphoric acid (3.6) can be added in one go within 2~3 minutes. When it is 5%, the phosphoric acid (3.6) can be added in batches within 5 minutes. When adding phosphoric acid, be sure to prevent carbon dioxide from escaping from the acid dropper funnel (C). After adding phosphoric acid (3.6), pass oxygen, let it stand for 23 minutes, heat the conical flask (B) at a low temperature until the solution is slightly boiling, and keep it for 10)min, then remove the electric heating plate (A). During this process, keep the gas flow rate at 34 bubbles/s through the drying tube (L). Then continue to keep it for 10 minutes to drive away the residual carbon monoxide.
Close the piston of the absorption tube, remove the absorption tubes (J) and (K), place them in a desiccant-free dryer in the balance room, and leave them for 30)min to balance the temperature. Open the pistons of the absorption tubes (J) and (K), and close them immediately to balance the internal pressure with the atmospheric pressure. Weigh. 7 Calculation of analysis results
Calculate the mass percentage of carbon dioxide according to the following formula: CO(%) = (m2 = m)
Where: m
mass of sample + gt
mass of carbon dioxide measured in the blank test, g; mass of the absorption tubes (J and K) before absorption, g; mass of the absorption tubes (J and K) after absorption·g; mo)×100k
K-conversion factor for the mass percentage of carbon dioxide in the completely dried sample. 8 Precision
The precision listed in this standard is the repeatability and reproducibility R obtained by conducting a joint test of eight laboratories in 1990-1991 on four uniformly distributed and identical homogenized samples within the measurement range of this method according to the analytical steps of this method, summarizing the data and conducting statistical analysis in accordance with the national standard GB6379, see Table 2. The original data are shown in Appendix A. Table 2
Level.%(m/m)
0. 115~18. 4
Repeatability r
lgr=—1.261 1+0.523 9 lgm
Reproducibility R
IgR=1.0468-0.5229 lgm
Repeatability is the maximum difference between two independent test results at the 95% probability level when two single test results are made by the same operator in the same laboratory, using the same instrument, and within a short period of time under normal and correct operation conditions. Reproducibility is the maximum difference between two independent results at the 95% probability level when two single test results are made by two operators in different laboratories under normal and correct operation conditions. If the difference between two independent test results exceeds the corresponding repeatability and reproducibility values, the two results are considered suspicious. Data
Laboratory
Additional Notes:
GB/T14949.11—94
Appendix A
Original data of precision test
(Supplement)
This standard is proposed by the Ministry of Metallurgical Industry of the People's Republic of China. CO2-3
This standard is drafted by the Mineral Geology Research Institute of China Nonferrous Metals Industry Corporation and the Changsha Mining Research Institute of the Ministry of Metallurgical Industry. This standard is drafted by the Changsha Mining Research Institute of the Ministry of Metallurgical Industry. The main drafters of this standard are Shi Zhisheng, Bai Qianzhen, Yang Jinxiu, Zhang Guying, Cao Shidiao, and Chen Ziruo. s
Tip: This standard content only shows part of the intercepted content of the complete standard. If you need the complete standard, please go to the top to download the complete standard document for free.