Significance and Use

This test method is useful for determining organic as well as inorganic chloride compounds that can prove harmful to equipment and reactions in processes involving hydrocarbons. The combination of both the organic and inorganic chloride is commonly termed total chloride and since the inorganic chlorides are partially recovered, the result for total chloride will be biased low.

Maximum chloride levels are often specified for process streams and for hydrocarbon products.

Organic chloride species are potentially damaging to refinery processes. Hydrochloric acid can be produced in hydro treating or reforming reactors and this acid accumulates in condensing regions of the refinery.

1. Scope

1.1 This test method covers the measurement of chloride in aromatic hydrocarbons, their derivatives, and related chemicals as defined by the method. Aromatics typically do not have any source of chlorides other than organic. The presence of metallic or inorganic chlorides is theoretically possible but not likely and this method does not purport to address recovery of those compounds.

1.2 This test method is applicable to samples with chloride concentrations from 0.24 to 5.0 mg/kg. The test method limit of detection (LOD) is 0.07 mg/kg.

1.3 This test method is preferred over Test Method D5194 for products, such as styrene, that are polymerized by the sodium biphenyl reagent.

1.4 In determining the conformance of the test results using this method to applicable specifications, results shall be rounded off in accordance with the rounding-off method of Practice E29 .

1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.

1.6 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. For specific hazard statements, see Section 9.

2. Referenced Documents (purchase separately) The documents listed below are referenced within the subject standard but are not provided as part of the standard.

ASTM Standards

D1193 Specification for Reagent Water

D1555M Test Method for Calculation of Volume and Weight of Industrial Aromatic Hydrocarbons and Cyclohexane [Metric]

D3437 Practice for Sampling and Handling Liquid Cyclic Products

D3505 Test Method for Density or Relative Density of Pure Liquid Chemicals

D4052 Test Method for Density, Relative Density, and API Gravity of Liquids by Digital Density Meter

D5194 Test Method for Trace Chloride in Liquid Aromatic Hydrocarbons

D6809 Guide for Quality Control and Quality Assurance Procedures for Aromatic Hydrocarbons and Related Materials

E29 Practice for Using Significant Digits in Test Data to Determine Conformance with Specifications

E691 Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method

Keywords

aromatic hydrocarbon; density; electrolysis; electrolyte; evaporation; microcoulometry; potential; pyrolysis; recovery; titration; total chloride; Chloride analysis; Electrolysis; Hydrocarbons (aromatic); Microcoulometry; Titration

ICS Code

ICS Number Code 71.080.15 (Aromatic hydrocarbons)

DOI: 10.1520/D7457-12

ASTM International is a member of CrossRef.

ASTM D7457