GB/T 6912-2008 English PDF

US$169.00 · In stock
Delivery: <= 3 days. True-PDF full-copy in English will be manually translated and delivered via email.
GB/T 6912-2008: Analysis of water used in boiler and cooling system -- Determination of nitrite
Status: Valid

GB/T 6912: Historical versions

Standard ID	USD	BUY PDF	Lead-Days	Standard Title (Description)	Status
GB/T 6912-2008	169	Add to Cart	3 days	Analysis of water used in boiler and cooling system -- Determination of nitrite	Valid
GB/T 6912.1-2006	159	Add to Cart	3 days	Methods for analysis of water for boiler and for cooling -- Determination of nitrates and nitrites -- Part 1: Ultraviolet spectrophotometry for nitrates	Valid
GB/T 6912.1-1986	199	Add to Cart	2 days	Methods for analysis of water for boiler and for cooling--The determination of nitrates and nitrites--Ultraviolet spectrophotometry for nitrates	Obsolete

Similar standards

GB/T 6913   GB/T 6907   GB/T 6903   

Basic data

Standard ID: GB/T 6912-2008 (GB/T6912-2008)
Description (Translated English): Analysis of water used in boiler and cooling system -- Determination of nitrite
Sector / Industry: National Standard (Recommended)
Classification of Chinese Standard: G76
Classification of International Standard: 71.040.40
Word Count Estimation: 7,713
Date of Issue: 2008-04-01
Date of Implementation: 2008-09-01
Older Standard (superseded by this standard): GB/T 6912.2-1986; GB/T 6912.3-1986
Quoted Standard: GB/T 602; GB/T 6682
Adopted Standard: ISO 6777-1984, NEQ
Regulation (derived from): National Standard Approval Announcement 2008 No.5 (Total No.118)
Issuing agency(ies): General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China, Standardization Administration of the People's Republic of China
Summary: This standard specifies the raw water, boiler water and cooling water Determination of nitrite content. This standard molecular absorption spectrophotometry applied to the raw water, boiler water and cooling water nitrite content of 0 mg/L ~ 0. 25 mg Determination/L, , ultraviolet spectrophotometry applied to the raw water, boiler water and cooling water nitrite content 0 mg/L ~ 25 mg/L of determination.

GB/T 6912-2008: Analysis of water used in boiler and cooling system -- Determination of nitrite

---This is a DRAFT version for illustration, not a final translation. Full copy of true-PDF in English version (including equations, symbols, images, flow-chart, tables, and figures etc.) will be manually/carefully translated upon your order.
ICS 71.040.40 G76 National Standards of People's Republic of China Replacing GB/T 6912.2-1986, GB/T 6912.3-1986 Analysis of boiler water and cooling water Determination of nitrite (ISO 6777. 1984, Waterquality-Determination of nitrite-Molecular absorptionspectrometricmethod, NEQ) 2008-04-01 release 2008-09-01 Implementation General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China China National Standardization Management Committee released

Foreword

This standard corresponds to ISO 6777. 1984 "Determination of water quality nitrite by molecular absorption spectrophotometry" (English version), and The degree of consistency of ISO 6777. 1984 is non-equivalent. This standard is used instead of GB/T 6912.2-1986 "Methods for analysis of boiler water and cooling water Nitrate and nitrite Nitrite and nitrite "and" GB/T 6912.3-1986 "boiler water and cooling water analysis methods Nitrate and nitrite Determination of α-Naphthylamine Hydrochloride Spectrophotometry ". This standard compared with GB/T 6912.2-1986 and GB/T 6912.3-1986, the main changes are as follows. --- The contents of GB/T 6912.2-1986 and GB/T 6912.3-1986 are modified and merged; --- α-Naphthylamine hydrochloride photometric method to molecular absorption spectrophotometry. This standard is proposed by the China Petroleum and Chemical Industry Association. This standard is under the jurisdiction of the National Chemical Standardization Technical Committee Water Treatment Agents Branch (SAC/TC63/SC5). This standard is responsible for the drafting unit. Tianjin Chemical Research and Design Institute. The main drafters of this standard. Liu Yanfei, Shao Hongqian, Li Lin. The standard version of this standard is released as follows. --- GB/T 6912.2-1986; --- GB/T 6912.3-1986. Analysis of boiler water and cooling water Determination of nitrite

1 Scope

This standard specifies the determination of nitrite content in raw water, boiler water and cooling water. The molecular absorption spectrophotometry in this standard is suitable for raw water, boiler water and cooling water nitrite content of 0mg/L ~ 0.25mg/L determination; UV spectrophotometry for raw water, boiler water and cooling water nitrite content of 0mg/L ~ 25 mg/L.

2 normative reference documents

The terms of the following documents are incorporated by reference in this standard and are the terms of this standard. Any reference to the date of the document, (Excluding corrigenda) or revisions do not apply to this standard, however, encourage the parties to reach an agreement under this standard Whether the latest version of these files can be used, and the most recent version of the referenced document, which is not dated, applies to this standard. GB/T 602 Preparation of standard solutions for the determination of impurities in chemical reagents (GB/T 602-2002, neq ISO 6353-1. 1982) GB/T 6682 Analytical laboratory water specifications and test methods (GB/T 6682-1992, neq ISO 3696. 1987)

3 molecular absorption spectrophotometry

3.1 Principles In the presence of pH = 1.9 and phosphoric acid, the nitrite in the sample reacts with the 4-aminobenzenesulfonamide reagent to form a diazonium salt, N- (1-naphthyl) -1, 2-ethylenediamine dihydrochloride solution (added simultaneously with 4-aminobenzenesulfonamide reagent) to form a pink dye. The absorbance was measured at 540 nm. 3.2 Reagents and materials The reagents used in this standard, unless otherwise specified, use only analytical reagents. Safety Tips. The strong acid used in this standard is corrosive, the color reagent is dangerous goods, should pay attention when used. Splash on the body, with a large number of Water rinse, avoid inhalation or contact with skin. 3.2.1 water, GB/T 6682, three. 3.2.2 phosphoric acid. 3.2.3 Phosphoric acid solution. 1 + 9. 3.2.4 Nitrite (in N) Standard stock solution. 100mg/L. Weigh (0.4922 ± 0.0002) g of sodium nitrite (dried at 105 ° C for at least 2 h) in about 750 mL of water. 1000mL volumetric flask and diluted with water to the mark. Store at 2 ℃ ~ 5 ℃ in a stoppered brown glass bottle, the solution can be stable Place for a month. 3.2.5 Nitrite (in N) Standard solution. 1.00mg/L. Remove the 10.00 mL nitrite standard stock solution (3.2.4) into a 1000 mL volumetric flask and dilute it to the mark with water. The day of preparation. 3.2.6 color reagent Weigh (40.0 ± 0.5) g 4-aminobenzenesulfonamide (NH2C6H4SO2NH3) was dissolved in a mixture of 100 mL of phosphoric acid and 500 mL of water (2.00 ± 0.02) gN- (1-naphthyl) -1, 2-ethylenediamine dihydrochloride (C10H7-NH-CH2NH2 · 2HCl) was added, To 1000mL volumetric flask, diluted with water to the mark, shake in 2 ℃ ~ 5 ℃ stored in a stopper with a brown glass bottle, the solution can be stable ......

Image     

Tips & Frequently Asked Questions:

Question 1: How long will the true-PDF of GB/T 6912-2008_English be delivered?

Answer: Upon your order, we will start to translate GB/T 6912-2008_English as soon as possible, and keep you informed of the progress. The lead time is typically 1 ~ 3 working days. The lengthier the document the longer the lead time.

Question 2: Can I share the purchased PDF of GB/T 6912-2008_English with my colleagues?

Answer: Yes. The purchased PDF of GB/T 6912-2008_English will be deemed to be sold to your employer/organization who actually pays for it, including your colleagues and your employer's intranet.

Question 3: Does the price include tax/VAT?

Answer: Yes. Our tax invoice, downloaded/delivered in 9 seconds, includes all tax/VAT and complies with 100+ countries' tax regulations (tax exempted in 100+ countries) -- See Avoidance of Double Taxation Agreements (DTAs): List of DTAs signed between Singapore and 100+ countries

Question 4: Do you accept my currency other than USD?

Answer: Yes. If you need your currency to be printed on the invoice, please write an email to Sales@ChineseStandard.net. In 2 working-hours, we will create a special link for you to pay in any currencies. Otherwise, follow the normal steps: Add to Cart -- Checkout -- Select your currency to pay.

Question 5: Should I purchase the latest version GB/T 6912-2008?

Answer: Yes. Unless special scenarios such as technical constraints or academic study, you should always prioritize to purchase the latest version GB/T 6912-2008 even if the enforcement date is in future. Complying with the latest version means that, by default, it also complies with all the earlier versions, technically.