Alkali Metal Ions and Their Effects on Smoldering and Ignition of Cotton Upholstery Fabrics-A Literature Review

Abstract

Several studies have previously suggested that alkali metal ions such as potassium and sodium play a critical role in the smoldering and ignition of cotton upholstery fabrics. We have conducted an extensive review of the relevant literature to identify potential sources of these ions and to delineate possible mechanisms by which they affect the smoldering and ignition of cotton upholstery fabrics. The hazard associated with the cigarette ignition of cotton upholstery fabrics is addressed in terms of statistics on fire fatalities. Potential sources of alkali metal ions on the cotton fiber have been identified as being (1) from soil and agricultural chemicals used during the growth of the cotton plant and (2) from alkali agents used in textile wet processes such as dyeing and finishing.A general framework and pathway of cellulose degradation, smoldering combustion and ignition to flaming combustion is presented. Potential effects of alkali ions on each of these processes have been analyzed. The most probable role of these ions is suggested to be a catalytic effect on the oxidation of carbonaceous char (smoldering combustion).

Burning characteristics and emission products related to metallic content in incense

“…Since alkali metal ions, such as Na and K, are generally used as enhancers in smoldering [11], they could be applied to incomplete combustion (incense, for example) to cut down on the air pollution. The major metallic content (include Na, Mg, Al, K, Ca and Fe) and incense burning characteristics (include the burning rate, the particulate and ash emission factors) under the same conditions are discussed below.…”

“…As Yeh's study [11] has indicated, alkali metal ions such as K and Na function as the enhancer in the combustion and smoldering combustion of cotton fabrics.…”

The Effects of Upholstery Fabric Properties on Fabric Ignitabilities by Smoldering Cigarettes

“…Also, the sources of these contaminants have been identified [8]. It is also known that these smolder promoters can be removed from cellulosic fabrics by a water rinse of the fabric itself, the yarn, or the raw cellulose fibers [5,6,9,10].…”

The Role of Alkali and Alkaline Earth Metal Ions in Cellulosic Smoldering

“…Other studies have concentrated on the role that alkali metal ions play in promoting cigarette-induced ignitions of upholstery fabrics [3][4][5][6]. Ihrig et al [3] defined the term &dquo;fabric proclivity,&dquo; based on the average smolder times of yarns in a fabric, the term is an excellent predictor of a fabric's ignition potential.…”