Cellulose dust

Some of the best blue flames are obtained from compositions based on potassium perchlorate, cuprous chloride, hexachloroethane, polyisobutylene, pyrotechnic copper powder and cellulose dust. 

The main species responsible for the blue flame from such a composition is cuprous chloride, CuCI hence the use of this salt together with the chlorine producer (hexachloroethane) and a source of extra copper (pyrotechnic copper powder). The cellulose dust acts as a moderator to control the burning rate of the pressed composition. 

Observe normal precautions appropriate to the circumstances and quantity of material handled. Hydroxyethyl cellulose dust may be irritant to the eyes and eye protection is recommended. Excessive dust generation should be avoided to minimize the risks of explosion. Hydroxyethyl cellulose is combustible. 

Because of their size-related large specific surface area, fine and ultrafme solid wastes, especially metallic fines or those containing metals or cellulosic dusts, are very reactive. Even at ambient conditions they combine easily with oxygen in an exothermic reaction that may cause accelerated, catastrophic heating or dust explosions . Size enlargement by agglomeration, accompanied by densification, sometimes... 

X- with cellulose dust need to condition filter before and after test. EH40/(latest issue) ... 

Cellulose esters, like most dry organic materials in powder form, are capable of creating dust explosions (133). The explosion at Bayer s cellulose acetate plant at Dormagen, Germany in 1976 can attest to the explosive potential of dust. Damage to the plant was estimated at between DM 5—10 million (134). 

Dry filters are usually deeper than viscous filters. The dry filter media use finer fibers and have much smaller pores than the viscous media and need not rely on an oil coating to retain collected dust. Because of their greater resistance to air flow, dry filters must use lower filtration velocities to avoid excessive pressure drops. Hence, dry media must have larger surface areas and are usually pleated or arranged in the form of pockets (Fig. 17-64), generally sheets of cellulose pulp, cotton, felt, or spun glass. 

Other possibilities are the reduction of nitro groups by applying the sample solutions to adsorbent layers containing zinc dust and then exposing to hydrochloric acid vapors [110] 3,5-Dinitrobenzoates and 2,4-dinitrophenylhydrazones can also be reduced in the same way on tin-containing silica gel phases [111] Cellulose layers are also suitable for such reactions [112] Seiler and Rothweiler have described a method of trans-salting the alkali metal sulfates to alkali metal acetates [113]... 

Igniters. A pellet composed of 26.5% K. perchlorate, 16.6% Ba nitrate, 53,9% 50/50 Zr/Ni alloy, and 3.0% et cellulose can be used to ignite solid propint grains (Ref 25), A series of mixts of K perchlorate with powd metals and other oxidizable mat were examined as substitutes for BikPdr as a gun primer. Most of the mixts tested were found to be satisfactory and to be compatible with brass and other metals (Ref 9) Incendiary Compositions. Stoichiometric mixts of K perchlorate with metals and oxidizable mat have been proposed as incendiaries of the Thermit type and have heats of reaction as follows Al dust 2504, powd Mg 2429. red P 1477, powd S 705 and powd C (lampblack) 1118cal/g (Ref 4). A mixt of 12.5% K perchlorate, 75% powd Zr, and 12,5% of a 50/50 Al/Mg alloy is reported to be a readily-ignited incendiary (Ref 20). Mixts of powd Al and/or powd Fe with K perchlorate with 1.5—2% NC as a binder are also good incendiaries (Ref 35). 

The change in structure of whole wood as in saw dust from birch (Fig. 13A) on hydrolysis (Fig. 3B) is easily observed. The changes in signals of cellulose are especially evident. 

Cellulose acetate dust (flocculated) o——o Pipe-line dusl, Copwell... 

See DUST EXPLOSION INCIDENTS (reference 15) See Calcium oxide Water (reference 3) Potassium chlorate Fabric, 4017 Nitric acid Cellulose, 4436 Hydrogen peroxide Acetic acid, Jute, 4477 See also COTTON... 

Cellulosics are fair insulators in a dry environment. For a polymer, electrostatic build-up is low, leading to moderate dusting. 

Wesley and Wall (19) collected and analyzed airborne dust samples collected from three areas within five Mississippi gins in 1975. The general composition of their samples are summarized in Table IV. These data show the dust to be about 30 percent cellulosic, the remainder being soil and other materials. The quantitative elemental analysis of their samples is detailed in Table V. Although the percentages are different, the constituents in these samples of gin dust are very similar to those listed by Brown (18) in whole plant parts. None of the data presented have identified residues from insecticides or harvest aid chemicals. This may be because they were not specifically sought. 

In the other study. X-ray fluorescence spectroscopy was used to analyze trace element concentrations by observing dusts on 37 ram diameter cellulose acetate filters (20). Twenty-three elutriator and twenty-three area samples from 10 different bales of cotton were analyzed. The average fraction of total dust accounted for by the elements analyzed was 14.4% amd 7.6% for vertical elutriator and area samples, respectively. Although the variation in absolute quantity of atn element was high, the relative abundance of an element was consistent for measurements within a bale. Averaged over all the samples analyzed, calcium was the most abundant element detected (3.6%), followed by silicon (2.9%), potassium (2.7%), iron (1.1%), aluminum (1.1%), sulfur (1.0%), chlorine (0.8%) and phosphorous (0.6%). Other elements detected in smaller aunounts included titanium, manganese, nickel, copper, zinc, bromine, rubidium, strontium, barium, mercury amd lead. 

A Typical Profile of Elements Measured by X-Ray Fluorescence in Cotton Dust Collected by a Vertical Elutriator on a Cellulose-Ester Filter (20)... 

Solid fires, e.g., cellulose fires involving material, such as wood, paper, dust, etc. 

Toxicology. Cellulose is inert and is classified as a nuisance dust. 

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