Sterilization methods and impact on electronics in medical devices | EE Times
"By “stealing” electrons from them (oxidation), CD breaks their molecular bonds, resulting in the death of the organism by the break up of the cell. Since CD alters the proteins involved in the structure of microorganisms, the enzymatic function is broken, causing very rapid bacterial kills." "potency of CD is attributable to the simultaneous, oxidative attack on many proteins, thereby preventing the cells from mutating to a resistant form. Additionally, because of the lower reactivity of chlorine dioxide, its antimicrobial action is retained longer in the presence of organic matter." "Due to the low temperature of +15° to +40°C, the CD sterilization process is well suited for medical devices with embedded electronics."
Effect of pipe corrosion scales on chlorine dioxideconsumption in drinking water distribution systems
"The corrosion scale will cause much more significant ClO2 loss in corroded iron pipes of the distribution system than the total organic carbon t... The application of ClO2 in the water distribution system using cast-iron pipes is not recommended unless measures to prevent corrosion are fully implemented . Although ClO2 loss caused by corrosion scale was much slower in the copper pipe ..., it may still be necessary to prevent the corrosion and unnecessary loss of disinfectant"
Methods and Solid Compositions for Generating Soapy and Non-Soapy Aqueous Solutions Containing Free Chlorine Dioxide
{Ingredients/additives for soap; slow-release CD powder} {John Thangaraj patent (SIPKA) for hand soap, etc.} "in the prior art, powder or granular preparations... were known to be substantially ineffective for producing chlorine dioxide unless the powder/granules were retained in a sachet or other water-permeable barrier that provided a controlled exposure to water. The use of polyacrylate... dispenses with that requirement." "Calcium and magnesium salts are not recommended for use as desiccators... since they add to the hardness of water and reduce soap properties. " "high stability of the chlorine dioxide soap solutions described herein is believed to be due to the presence of certain surfactants... chlorine dioxide is even retained on the surface to which it has been applied (e.g., during cleaning, etc.) for a longer period of time in the presence of a surfactant(s)" "a relatively high yield of chlorine dioxide is obtained from a solid composition that has a relatively greater amount of acid and a relatively lesser amount of alkali chlorite salt" "Anionic, non-ionic, and cationic surfactants that include nitrogen-containing compounds, such as amines, ammonia, quaternary ammonium salts, or urea, are generally not suitable for use in conjunction... [because] readily react with chlorine dioxide, interfere with its release, or otherwise reduce its concentration" "one or more of fillers, disintegrates for tablet formulations, thickeners, and/or foaming agents are also incorporated"
Common Uses and P.P.M. General Reference Guide This chart is for general reference only. Some applications such as commercial water applications may require a different ppm or CT time depending on the specific application, amount of contamination, and microbes being targeted. This chart is representative of the amounts of chlorine dioxide known to be used for applications based on product information, EPA, and FDA reports. PLEASE NOTE: OUR PRODUCTS ARE NOT REGISTERED BY THE E.P.A. AND ARE OFFERED ONL
{Includes more useful info, as well} "Bubnis (2009) reported the loss of chlorine dioxide in ballast water. This experiment clearly demonstrated that any chlorine dioxide residuals that might be present following the treatment of ballast water will quickly be consumed by dilution and demand. Chlorine dioxide and its transformation products (chlorite and chlorate) showed similar demand features when tested in divers waters. The author observed an initial fast demand for chlorine dioxide along with a slower continuing loss of chlorite and chlorate ions." "Photodecomposition of chlorite in aqueous solution is rapid with a half life of about 10 minutes depending on concentration. Oxygen, chloride and chlorate are produced as stable end-products with the formation of chlorine and chlorine dioxide as intermediates."
{This statement likely is not actually very applicable for chlorine dioxide used separately: "Another study (4) indicates that exposure to water over-saturated with all (3) common disinfectants – chlorine, chloramine and chlorine dioxide significantly affected stability of PEX pipe during testing, making the pipe more brittle and prone to cracking. This is another important reason to assure that your PEX plumbing pipe meets ASTM F2023 standard for resistance of PEX to chlorine. There exist opinions that F2023 is not comprehensive since it does not include chloramine and chlorine dioxide testing, but the study evidence suggests it is not necessary since all (3) disinfectants affect the pipe in a similar manner. "
Chlorine dioxide gel and associated methods - Google Patents
A method of making a composition having the property of being able to store chlorine dioxide includes mixing an aqueous chlorine dioxide solution with a superabsorbent, water-soluble polymer that is substantially unreactive with chlorine dioxide and permitting a mixture formed thereby to form one of a gel and a solid composition. A method of delivering chlorine dioxide includes providing a gel or solid composition as described and degelling the gel or dissolving the solid composition to dispense the chlorine dioxide therefrom. A method of disinfecting a target such as water, wastewater, or ...
Loss of chlorine, chloramine or chlorine dioxide concentration following exposure to UV light
"It was confirmed that chemical disinfectants decay when samples are exposed to UV light. Specifically, for deionized water free chlorine was lowered to approximately 95% of initial concentration following UV treatment. In contrast, free chlorine was decreased to 89% and 84%, on average, in the tested groundwater and surface water, respectively. A similar range in decreased disinfectant concentration was also observed for chlorine dioxide and chloramines. However, no significant absorption of UV irradiation by chemical disinfectants was observed."
WO2010002974A1 - Uv-based production of chlorine dioxide from chlorate or chlorite - Google Patents
Chlorate including sodium chlorate is used to produce chlorine dioxide gas upon exposure to ultraviolet radiation in the presence of a suitable catalyst. Chlorine dioxide gas can be used to disinfect, bleach and for a variety of industrial and commercial purposes. A Teflon®-coated UV lamp is optionally used to irradiate a solution of chlorate.
Photodecomposition of Chlorine Dioxide and Sodium Chlorite in Aqueous Solution by Irradiation with Ultraviolet Light | Industrial & Engineering Chemistry Research
Evaluation of chlorine dioxide based product as a hatchery sanitizer - ScienceDirect
The application rate of chlorine dioxide based product evaluated in this study was not an effective antimicrobial alternative to formaldehyde for sanitizing hatching eggs in hatcher cabinets prior to hatch.
Aging Mechanism of Polyethylene Pipe Material in Chlorine Dioxide and Hypochlorite Solution
PDF | SHORT SUMMARY (One paragraph, ~6 sentences) Accelerated aging experiments by the immersion of a commercial polyethylene (PE) pipe grade in 10 ppm... | Find, read and cite all the research you need on ResearchGate
Disinfection of Poultry Chiller Water with Chlorine Dioxide: Consumption and Byproduct Formation | Journal of Agricultural and Food Chemistry
Chlorine dioxide is effective in controlling the natural flora occurring in poultry chiller water (PCW). However, it is not approved for use as a disinfectant because of the lack of information pertinent to its human health risks. In PCW, most added chlorine dioxide was rapidly reduced to chlorite and chlorate. The formation of chlorite was dependent on both chlorine dioxide dose and treatment time. The chlorine dioxide demand by PCW, the consumption at a given treatment time, was found to be independent of treatment dose. When used at the demand level, half of the added chlorine dioxide was reduced to a mixture of chlorite (90%) and chlorate (10%). On the basis of the acceptable daily intake of chlorite, 0.075 mg/kg, disinfecting PCW at the level of chlorine dioxide demand, 0.30 mM (20 mg/L), is not only effective but also has a low health risk from the standpoint of chlorite and chlorate contamination.
Experience With Chlorine Dioxide in Brussels: Generation of Chlorine Dioxide - Masschelein - 1984 - Journal AWWA - Wiley Online Library
The yield of chlorine dioxide (ClO2) is influenced by chemical conditions (e.g., initial chlorine concentration, alkalinity) and by reactor design (e.g., detention time, method for mixing chemicals)....
Chlorine Dioxide Disinfection in the Use of Individual Water Purification Devices ~Military/gov-related
****{Summary of specific characteristics***a 35 mg/L chlorine dioxide solution stored in a high-density Polyethylene Terephthalate (PETE) container for 45 days resulted in a 3% loss.. In contrast, the same study stored chlorine dioxide in a clear glass container for 31 days which resulted in a 12% gain, possibly due to continuing formation of chlorine dioxide from chlorite. Another study showed a 6.2% overall gain in chlorine dioxide concentration after 252 days of storage in a PETE container... Chlorite and chlorate show no disinfection capabilities and may cause adverse health effects in children... CTs required for a 2-log virus inactivation were 13 – 20 times higher at a pH of approximately 6 compared to a pH of 9 and 10... two to three-fold increase in inactivation rates per 10° C water temperature increase... bentonite appeared to offer protection or shield the viruses from chlorine dioxide... disinfection capability decreases in more turbid waters since microorganisms are protected by solid particles in water, protected by aggregation or clumping, and protected by loss of chlorine dioxide residual from oxidation of organic matter... Chlorine dioxide should easily achieve a 6-log *bacteria* inactivation at low temperatures and low pHs if chlorine dioxide is used for disinfection of more resistant viruses and cysts." "Colder water temperatures require higher CT values. Use a two-fold increase in CT for every 10° C decrease. Use longer contact time instead of higher dosages to achieve higher CT values. "
Chlorine dioxide is a chemical compound with the formula ClO2. This yellowish-green gas crystallizes as bright orange crystals at −59 °C. As one of several oxides of chlorine, it is a potent and useful oxidizing agent used in water treatment and in bleaching.
*****"[Note: Some statements about corrosion, reaction with phenols, Cl also released during some specific reactions, etc may have some inaccuracies] Like ozone and chlorine, chlorine dioxide is an oxidizing biocide and not a metabolic toxin. This means that chlorine dioxide kills microorganisms by disruption of the transport of nutrients across the cell wall, not by disruption of a metabolic process." "Unlike chlorine, Chlorine dioxide is effective at pH between 4 and 10. No dumping and filling with fresh water required;" "Chlorine dioxide can be used as a spray. All parts therefore, can easily be reached;" In scrubbers: "In scrubbers, Usually, a very low chlorine dioxide residual, around 0.2-ppm, is sufficient to ensure odour control." {includes effects on specific foods when rinsed}
What is the equivalent weight of citric acid? - Quora
"equivalent weight = molecular weight/ basicity
Citric acid could be anyhydrous as well as monohydrous, and so the molecular weight varies accordingly.
anhydrous : C6H8O7 = 192.12 mg/mol
hydrous: C6H8O7.H2O = 210 mg/mol
also, cirtic acid is a weak acid and doesn't oxidize completely when added to a base; it donates only a few (about 3) protons (H+). This is the basicity of the acid.
Therefore, equivalent weight of citric acid= 210/3= 70 (when it is monohydrous)
or 192.12/3=64.4 ( when it is anyhydrous)"
{ists references to all Gov regulatory info sources re. SC and CD}{includes % & ingredients of tech-grade and various other SC products} "Sodium chlorite is available in both dry and liquid forms. The dry forms contain approximately 80% Sodium chlorite and the solutions range from 7.5% to 40% sodium chlorite."
Guidelines for Drinking-water Quality, Fourth Edition - chloride-chlorate-fs-new.pdf
" it is normal practice to supply water with a chlorine dioxide residual of a few tenths of a milligram per litre to act as a preservative during distribution" "The taste and odour threshold for this compound is 0.4 mg/l."
How sodium chlorite is made - material, production process, manufacture, making, history, used, processing, composition
****{Components of Sodium Chlorite} "Other materials are typically added to sodium chlorite powders or solutions before they are sold. Commercial sodium chlorite bleaching solutions contain special ingredients including anticorrosive agents, buffering agents, chlorine dioxide fume controllers, and surfactants. Anticorrosive agents are used to prevent the corrosion of stainless steel bleaching equipment. Buffer salts help liberate the chlorine dioxide that is produced during the bleaching process. Surfactants help stabilize solutions and allow for cleaning and penetration effects. Stabilized sodium chlorite solution can be stored for long periods without loss of activity. When the sodium chlorite is sold as a solid, sodium chloride is often included to make it safer to handle and store."