Note: Descriptions are shown in the official language in which they were submitted.
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DEVICES, SYSTEMS, AND METHODS OF MAKING AND USING CHLORINE
DIOXIDE BASED FORMULATION WITH IMPROVED STABILITY
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a continuation-in-part to U.S. Patent
Application No.
15/997,660, filed on June 4, 2018, which is related to U.S. Application No.
14/631,806
titled BROAD SPECTRUM DISINFECTANT, filed on February 25, 2015, which claims
priority to U.S. Provisional Application No. 61/945054, filed February 26,
2014, which are
incorporated herein by reference.
FIELD
[0002] The present invention is generally related to broad spectrum
disinfectants, sanitizers, cleaners or deodorizers using chlorine dioxide
compositions, and
more particularly, to methods for producing chlorine dioxide compositions
having
improved long term stability by the proper choice of pH and through the
careful choice of
other product formula ingredients.
BACKGROUND
[0003] For a product to be successful in the marketplace, it must have
suitable
shelf life stability, in addition to, providing the desired function and
aesthetics. Disinfecting
or sanitizing products require a suitable biocidal agent. Some examples of
biocides are
chlorine dioxide, hypochlorite, peroxide, and quaternary amines. Many products
containing reactive ingredients such a chlorine dioxide (CI02) have problems
with long-
term stability, thus limiting their shelf-life. Chlorine dioxide is an
effective biocide and can
clean and deodorize. One particular advantage of C102 over hypochlorite is
that C102
does not chlorinate organic compounds. However, it is inherently less stable
than other
biocides such as quaternary amines. Due to instability, most applications
involve
producing chlorine dioxide at the source of use. Therefore, chlorine dioxide
must be
properly formulated to be viable.
[0004] Products containing chlorine dioxide generally have a limited
shelf life
because chlorine dioxide decomposes over time even in closed bottles.
Typically,
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unstable products will have a use by or expiration date to ensure that the
product's
designated performance, such as micro efficacy, is maintained throughout the
time
period. Manufacturing and inventory control, as well as, maintaining
microbiological
efficacy are therefore challenging for product with limited lifetime. Due it
its inherent
instability, chlorine dioxide is often produced at the source using a chlorine
dioxide
generator. Another approach is to market a 2-Part (or multipart) product where
the
precursors of the active ingredients are mixed/reacted at the point of use,
and then specify
an appropriate time period to use the product. However, 2-Part products
generally require
more complex packaging, and require the consumer to perform an extra "mixing"
step
before using. There is also a risk that that the mixing /reacting step is not
followed
properly. This extra mixing step may not be desirable to the consumer and the
consumer
may prefer an alternative product. Yet another approach could be use a package
and a
trigger/pump dispenser system that keeps the reagents separated until use. In
this
scenario, a multiple (dual) chamber bottle equipped with a trigger/pump
actuator having
a dip (supply) tube inserted in each chamber such that when the trigger/pump
actuator is
used, aliquots from both chambers are simultaneously drawn and mixed when
dispersed.
This approach would require a more complex bottle and trigger/actuator due to
the
multiple product streams.
[0005] In view of this, it is desirable to develop a disinfectant or
sanitizing or
cleaner/deodorizer product that maximizes the stability of the active
ingredients so that
the product has a suitable shelf-life and is ready to use after manufacturing.
Stable
products have a longer shelf-life, better consumer appeal, and are easier to
use. A stable
product can use conventional package that are readily available and cheaper.
SUMMARY
[0006] In one aspect, the invention is a device for delivering
stabilized chlorine
dioxide having improved long term stability by the proper choice of pH. A
number of
synthesis reactions are known for producing chlorine dioxide. The preferred
method is
the acidification of chlorite.
[0007] The device includes a delivery device configured to deliver a
solution to
a target application and a stabilized chlorine dioxide (CI02) product that is
configured to
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be delivered using the delivery device. The chlorine dioxide is produced using
a method
that includes adding a first amount of Hydrochloric acid (HCI) to a second
amount of
Sodium chlorite (NaCI02) that is dissolved in water, the first amount being
greater than
the second amount; agitating the HCL and NaC102 for at least 10-15 minutes to
mix the
chemicals and thus allowing the chemical to react to completion; adding a
third amount
of Dowfax to the solution and slowly agitate the HCI, NaC102 and Dowfax
solution to
distribute the Dowfax; and after the reaction to generate chlorine dioxide
(CI02) in
solution has gone to completion, adding a fourth amount of Sodium Hydroxide
(NaOH) to
adjust the pH of the resulting C102 solution to a desired pH and
concentration.
[0008] In another aspect, the invention is a method of making a high
concentration chlorine dioxide with improved long-term stability comprising.
The method
includes adding 42.61g/I 10% Hydrochloric acid (HCI) to 3.20g/I Sodium
chlorite (NaCI02)
dissolved in water; agitating the HCL and NaC102 for at least 10-15 minutes to
mix the
chemicals; adding 1.50g/I of Dowfax and slowly agitate the HCI, NaC102 and
Dowfax
solution to distribute the Dowfax; and adding 42.23g/I of 5% Sodium Hydroxide
(NaOH)
to adjust the pH of the C102 solution to a desired pH.
[0009] In another aspect, the invention is a method for producing a
high
concentration chlorine dioxide with improved long-term stability. The method
includes 1)
adding a molar excess concentration amount of Hydrochloric acid (HCI) to an
amount of
Sodium chlorite (NaCI02) dissolved in an amount of water; 2) agitating the HCL
and
NaC102 until the reaction to form chlorine dioxide (CI02) is complete; 3)
adding an
amount of Dowfax and slowly agitating the HCI, NaC102 and Dowfax solution to
distribute
the Dowfax; and 5) adding an amount of Sodium Hydroxide (NaOH) to the C102
solution
to adjust the pH to a target value; wherein: the molar excess concentration
amount of
acid = 42.61g/I 10% HCI; the amount of sodium chlorite = 3.20g/I NaC102 (80%);
the
amount of Dowfax = 1.50g/I Dowfax: the amount of NaOH =42.23g/I of 5% NaOH;
the pH
target value approximately 4.5 -6.5.
[0010] In some embodiments, the delivery device is a spray bottle and
the
stabilized C102 is a sprayable solution; the delivery device is a wipe and the
stabilized
C102 is a solution integrated into the wipe; the delivery device is a tablet
and the
stabilized C102 is integrated into the tablet; the delivery device delivers a
laundry
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detergent and the stabilized C102 is integrated into the laundry detergent;
the delivery
device delivers a deodorizer and the method of producing the C102 further
comprises
adding a fragrance ingredient compatible with CI02; the delivery device is a
cleaning
device and the stabilized C102 is produced as a concentrate that can be used
at full
strength or diluted with water.
[0011] In some embodiments, the desired pH 4.5 -6.5; in some
embodiments
the desired pH is 5.91. In some embodiment the C102 concentration is 1200-1300
PPM.
In some embodiment the C102 concentration is 1250 PPM
[0012] In some embodiments, the C102 is: a sprayable solution
configured to
work with a spray bottle; the C102 is a concentrated solution configured to be
used at full
strength or diluted with water prior to use; the method further comprising
adding a
fragrance ingredient compatible with C102 to produce a fragranced solution.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] The foregoing and other features of the present disclosure will
become
more fully apparent from the following description and appended claims, taken
in
conjunction with the accompanying drawings. Understanding that these drawings
depict
only several embodiments in accordance with the disclosure and are not to be
considered
limiting of its scope, the disclosure will be described with additional
specificity and detail
through the use of the accompanying drawings.
[0014] Figure 1 shows a stability profile of chlorine dioxide
compositions with
differing pH levels vs. time.
[0015] Figure 2 shows a stability profile of chlorine dioxide and
surfactant
compositions with differing pH levels vs. time.
[0016] Figure 3 shows a stability profile of chlorine dioxide and
surfactant
compositions with differing pH levels vs. time.
[0017] Figure 4 shows a stability profile for a series of samples with
Dowfax
362.
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[0018] Figure 5 shows a plot of the percent of C102 remaining as a
function of
pH.
DETAILED DESCRIPTION
[0019] Embodiments of the invention will now be described with
reference to
the figures, wherein like numerals reflect like elements throughout. The
terminology used
in the description presented herein is not intended to be interpreted in any
limited or
restrictive way, simply because it is being utilized in conjunction with
detailed description
of certain specific embodiments of the invention. Furthermore, embodiments of
the
invention may include several novel features, no single one of which is solely
responsible
for its desirable attributes or which is essential to practicing the invention
described
herein.
[0020] The present invention is directed to improve the stability of
chlorine
dioxide (CI02) compositions and products. The inventor has found that the
stability of
the chlorine dioxide can be significantly improved by the proper choice of pH,
and through
the careful choice of other product formula ingredients. By maximizing the
stability of
chlorine dioxide, the product has a suitable shelf-life and is ready to use
after
manufacturing. This stabilization benefit applies regardless of the reaction
method used
to produce chlorine dioxide.
[0021] The improved stability of C102 is due to adjusting the pH. The
relationship between pH and stability may not be recognized, and that could
explain the
limited number of C102 based product in the market. The increased stability of
C102
would make a product more desirable than a similar product with limited shelf-
life, or a
product that must be mixed prior to use.
[0022] Chlorine dioxide (C 102) can be produced by a number of
reactions with
sodium chlorite (NaCI02). Several industrial methods of synthesis of chlorine
dioxide are
known such as acidification of chlorite, oxidation of chlorite by chlorine,
oxidation of
chlorite by persulfate. Other suitable reactions include the reaction of
acetic anhydride
with chlorite, the reduction of chlorates by acidification in the presence of
oxalic acid, and
the reduction of chlorates by sulfurous anhydride. Acidification of chlorite
according to the
following reaction is particularly appealing due to the availability, cost and
ease of use of
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hydrochloric acid. It is understood that regardless of the method used to
produce chlorine
dioxide, the stability of the solution is controlled by pH and the proper
choice of other
ingredients.
[0023]
Any suitable acid may be used in the process disclosed. For example,
but not limited to, hydrochloric acid, sulfuric acid, nitric acid, phosphoric
acid, acetic acid,
citric acid, sulfamic acid, succinic acid, and oxalic acid.
[0024]
Acids may be moderate to strong acids that are capable of reacting with
sodium chlorite to form C102. The strongest acids are "mineral acids." Common
examples are hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid.
These are
characterized as having pKa values <1. Strong acids react very quickly with
sodium
chlorite.
[0025]
Moderately strong acids include many organic acids. Examples include
acetic acid, citric acid, sulfamic acid, succinic acid, and oxalic acid.
These are
characterized as having pKa values pKa about 5. The acid needs to react with
sodium
chlorite to form C102. If the pka is too high, the reaction will not occur or
will be very slow.
The lower the pKa, the stronger the acid and the faster the reaction with
sodium chlorite.
[0026]
The process may also include a caustic, such as sodium hydroxide to
adjust the solution pH
[0027]
(Reference: Chlorine Dioxide by W.J. Masschelein, Ann Arbor Sciences
1979.)
[0028]
For example, sodium chlorite (NaCI02) and hydrochloric acid (HCI),
shown in Formula (1).
4HCI + 5NaC102 4C102 + 2H20 + 5NaCI (1)
[0029]
It is generally desirable to have an excess of HCI because it helps speed
the reaction and maximizes the conversion of NaC102 to C102. The resulting pH
of
samples typically produced this way is pH <2.
[0030] EXAMPLE 1
[0031]
A first batch of C102 (3-134), prepared as described in Formula (1) was
split into two subsamples. The pH of one subsample was adjusted to pH 3.66
with
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Sodium Hydroxide (NaOH) (3-134A) and the other subsample was not adjusted and
was
pH 1.70 (3-134B). A second batch of C102 (3-131), prepared as described in
Formula
(1) at a lower concentration of C102 split into two subsamples. The pH of one
subsample
was adjusted to pH 3.62 (3-131A) and the second subsample was not adjusted and
was
pH 1.96 (3-131B). The samples were stored in closed amber glass jars. At
various times,
aliquots were removed and the C102 was assayed using the iodometric titration.
[0032] Figure 1 is a plot of the C102 concentration vs. time for the
samples. As
seen in the plot, increasing the pH results in a much more stable product,
i.e. slower loss
of the C102 concentration over time. Raising the sample pH also has the key
benefit of
preventing the initial rapid drop in C102 typically seen in the first few days
after synthesis
of CI02. Preventing this initial drop in activity is more cost effective for
manufacturing
and makes it easier to achieve the desired concentration.
[0033] EXAMPLE 2
[0034] Figure 2 shows a stability profile of another set of samples
with
surfactant added (3-142), in this case, Dowfax 3B2 surfactant. The C102 (3-
142) was
prepared as described in Formula (1) and split into two subsamples. The pH of
one
subsample was adjusted to pH 3.64 (3-142B) with Sodium Hydroxide (NaOH) and
the
other subsample was not adjusted and was pH 1.73 (3-134A). Both samples were
stored
in closed amber glass jars. At various times, aliquots were removed and the
C102 was
assayed using the iodometric titration. Figure 2 is a plot of the C102
concentration with
vs. time. This plot again shows increasing the pH to 3.64 results in a much
more stable
product than the pH 1.73 sample, i.e. slower loss of the C102 concentration
over time.
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[0035] EXAMPLE 3
[0036] Figure 3 shows a stability profile of another set of samples
with
surfactant added (3-170), in this case, Dowfax 3B2 surfactant. Figure 3 is
similar Figure
2 but with samples at a broader range in pH. The C102 with surfactant was
prepared as
described and split into seven subsamples. The pH of the first subsample 3-
170A was
not adjusted and was pH 1.76. The pH of the other subsamples 3-170B to 3-170G
were
adjusted with Sodium Hydroxide (NaOH). All samples were stored in closed amber
glass
bottles.
3-170 A pH 1.76
3-170B adjusted to pH 2.34
3-170C adjusted to pH 3.00
3-170D adjusted to pH 3.64
3-170E adjusted to pH 4.17
3-170F adjusted to pH 4.97
3-170G adjusted to pH 7.18
[0037] Figure 3 shows the effect of pH on stability. The graph shows
raising
the pH in subsamples 3-170B to 3-170G improved stability. However, sample 3-
170G
with pH 7.18 was not as stable as the samples as pH 4.97 (3-170F), suggesting
there
may be an optimal pH range for stability where pH -5 appears to have better
stability than
pH 3.6.
[0038] EXAMPLE 4
[0039] Figure 4 shows the stability profile for yet another series of
samples with
Dowfax 3B2 (Sample series 3-176A-J). The same procedure was used in preparing
the
samples. A large sample batch was prepared which was then split into ten sub
samples.
The pH of the subsamples was adjusted by addition of sodium hydroxide. The
samples
were stored at room temperature in closed amber glass bottles. At various
times,
aliquates from the subsamples were removed and the concentration of C102 was
assayed
using an iodometric titration. The sample pH's were checked and adjusted if
necessary
to the original sample pH. The initial concentration of C102 was 545 PPM.
Table A shows
the concentration of C102 and the corresponding calculated percent remaining
based on
the initial concentration. at 6, 14 and 37 weeks.
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Table A
Sample 6 week 14 week 37 weeks
pH C102 Percent C102 Percent C102 Percent
PPM Remaining PPM Remaining PPM Remaining
1.77 377 69.2 298 54.7 162 29.8
3.60 493 90.4 460 84.4 386 70.8
4.06 508 93.2 460 86.1 410 75.3
4.49 526 96.5 503 92.3 459 84.2
5.03 515 94.5 487 89.4 458 84.1
5.52 516 94.7 484 88.8 440 82.4
6.02 520 95.4 483 88.6 451 82.8
6.48 528 96.9 496 91.0 450 82.6
7.01 503 92.3 473 86.8 442 81.1
8.17 482 88.4 447 82.0 427 78.3
Sample 3-176 A-J
Figure 5 shows a plot of the percent of C102 remaining as a function of pH at
the T=37-
week data using the data from Table A. The profile shows the improved
stability resulting
from increasing the samples pH with the optimal pH at -5 consistent with the
data shown
in Figure 4.
[0040] General Instructions
[0041] All chemicals are used without further purifications. All
samples bottles
used were amber and appropriately labeled. Each container was rinsed with
deionized
water before reusing.
[0042] All processes and reactions are carried out at room temperature
not
exceeding (22 C) unless otherwise specified.
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[0043] The present invention may be used for various products,
including, for
example, a surface disinfectant or sanitizer. While the present application
discloses
embodiments for a surface disinfectant, it is contemplated that the same
processes,
methods, and solutions may be used for the other products.
[0044] Basic Solution
[0045] Below is one example of chlorine dioxide based final formulation
with
improved stability.
1 Hydrochloric acid solution (NCI).
2 Sodium chlorite (NaC102).
3. Sodium Hydroxide (NaOH)
4 Deionized water (H20).
[0046] Chlorine Dioxide Composition Products Types
[0047] Table 1 below shows a base solution composition used for
disinfectant/sanitizer solution depicted in Figure 1 3-134 A/B. As described
above,
NaC102 is dissolved in deionized water. The aliquot of 10% HCI was added. The
mixture
is stirred and allowed to react for 15 minutes. The batch was then split into
two 11
subsamples.
Table 1
Product type pH adjusted Base Solution
1 2 3 4
Disinfectant 34.10 g 10% 2.56 g See below 1963 g H20
HCL
32 g of 5% NaOH was added to a 1 liter sample of 3-134B with a resulting pH of
3.66
32g of H20 was added to Samples 3-134A to insure the
identical volume both samples. The pH of 3.134A was 1.70.
[0048] Surfactant Solution
[0049] Below is one example of chlorine dioxide-based formulation
having a
surfactant with improved stability.
1 Hydrochloric acid solution (NCI).
2 Sodium chlorite (NaC102).
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3. Surfactant (for example, DOWFAX 362).
4. Sodium Hydroxide (NaOH)
Deionized water (H20).
[0050] Table 2 below shows some example ranges as used in Figure 2.
Table 2
Product type pH adjusted with Surfactant (g/liter)
1 2 3 4 5
Disinfectant 17 g 10% 1.28 1.5 16 g 5% 980
HCL NaOH
[0051]
Chlorine dioxide (CI02) decomposes more quickly when exposed to
light, is temperature sensitive and it reacts with many organic compounds.
Proper
shielding from light and clean production facilities and handling procedures,
and material
purity are essential to improve stability and avoid unwanted reactions with
organic
contaminants during production.
[0052]
The resulting concentration of chlorine dioxide can be tailored to meet
the desired biocidal performance. As with many biocidal products, the product
of the
concentration and the contact time I.e. c x t = constant. As a simplistic
approximate
relationship, doubling the concentration can result in a reduction of
concentration to yield
a similar degree of micro efficacy.
[0053] Table 3 shows typical ranges of ingredients to produce
sanitizer/disinfecting/deodorizing solutions.
Table 3
Component Wt Percent
NaC102 0.0050 - 0.90
HC1 0.0016 ¨ 11.00
Surfactant 0.00 - 3.00
NaOH 0 ¨ 0.90
H20 balance
Total 100.0
[0054]
It is understood that a practical method of making a very dilute solution
of chlorine dioxide, at concentrations as low as 1 PPM, can be prepared by
further dilution
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of a more concentrated solution using deionized water. The lower limit
represents the
stoichiometric limit from Formula 1.
[0055] Higher Product Concentration
[0056] The examples described above had a starting concentration of
about
550 PPM C102. The present invention also contemplates making a solution of
chlorine
dioxide with higher concentration 1200-1300 PPM having a pH 4.5-6.5 for
various
applications. The upper limit of HC1 assumes a several fold molar excess of
HC1to speed
the reaction rate.
[0057] Table 4 shows an example of ingredients for producing a product
having
about 1250 PPM C102 and Ph 5.91.
Table 4
Component Wt Percent or Grams per Liter
NaC102 0.320 3.20g/1
10% HC1 4.261 42.61g/1
Dowfax 0.150 1.50g/1
NaOH 4.230 42.23g/1
H20 balance balance
Total 100.0 100.00
[0058] A batch of the 1250 PPM C102 was prepared as described in Table 4
and was split into two subsamples. The pH of one subsample was not adjusted
and was
pH 1.50 and the second subsample adjusted using 42.3 gm of 5% NaOH to a pH
5.91.
[0059] The sample of the adjusted pH 5.91 and the non-adjusted pH 1.50
formula were titrated at various times out to 8 months. At 8 months, the
control non-
adjusted pH 1.50 sample lost 92% (8% remaining) and the adjusted pH 5.91
sample lost
27% (74% remaining) activity.
[0060] The 550 PPM C102 initial concentration losses after 8 months
was
-15%. Hence, the percentage of loss increases with concentration even with pH
adjusted
samples. The limit of how high a concentrated product can be made depends on
the
amount of acceptable concentration loss over time. It appears that a high
concentrated
product may be acceptable for if the time period for use is shorter than a
lower
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concentrated product. This may also depend application of the product. While
the above
sample was 1250 PPM, higher concentrations are also contemplated.
[0061] Production Process
[0062] The production/manufacturing for the C102 based solution should
follow
general manufacturing guidelines that are typically followed in the production
of
hypochlorite or peroxide containing based products. All contact surfaces in
the production
equipment, filling and line and packaging should be in good condition. They
must/should
be emptied and thoroughly rinsed so as to prevent cross contamination prior to
use. Such
practices are generally followed in the production of hypochlorite containing
products or
other products where contamination is undesirable/not tolerated.
[0063] Preferably, the entire production process for the solution
would be
conducted under clean room conditions, in order to minimize the possibility of
contamination of the solution by environmental contaminants, such as airborne
particles.
All contact surfaces, including without limitation surfaces of production
equipment, filling
equipment and packaging, should be thoroughly cleaned of contaminants prior to
use.
[0064] Batch Process for Preparation of Chlorine Dioxide
[0065] Ranges for the amounts of the Solutions to be used for each
embodiment are shown above.
1. Prepare the mixing vessel by decontaminating the container with chlorine
dioxide followed by a rinse with deionized water. If the container is used
regularly, the container may be rinsed with only deionized water.
2. Add deionized water corresponding to size of the batch followed by the
sodium
chlorite. Allow the sodium chlorite to completely dissolve. Agitate the sodium
chlorite solution.
3. Add the hydrochloric acid to the sodium chlorite solution. After the
hydrochloric
acid is added, the vessel should be loosely capped to allow the release of any
gas that may have formed in the container. The amount of gas formed will vary
depending on the concentrations of hydrochloric acid and sodium chlorite
present.
4. Allow the acid-chlorite mixture to react for 10-15 minutes with slow
agitation.
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5. Add the surfactant. Mix or slowly agitate to distribute the surfactant.
6. Adjust the pH with sodium hydroxide solution to achieve the target pH for a
stable solution. It is recommended that a pH meter be used to monitor the pH.
7. Store samples in sealed opaque/dark containers.
In the procedure described above, it is also generally acceptable to add the
surfactant to the dissolved sodium chlorite before adding the HCI. Allow the
chlorite-surfactant-acid mixture to react with slow agitation and then adjust
the
pH with sodium hydroxide.
[0066] Continuous Process Preparation of Solution
[0067] Below shows one embodiment of a continuous process for
preparing
chlorine dioxide Surface Disinfectant.
A. Turn on the water pump in the reactor unit and adjust the deionized water
to
the desired feed rate.
B. Turn on the chemical solutions feed pumps and set the feed rates to the
desired
percentage of hydrochloric acid, sodium chlorite and surfactant (optional).
The
sodium hydroxide can be added downstream to adjust the pH.
C. Assure proper mixing of the water and chemicals.
[0068] Dilution ¨ Preparation of Finished Product
[0069] Deionized water should be used to prepare or dilute the
Solution during
production of the finished product. The pH of the finished product should be
adjusted to
improve stability and/or to achieve the desired product pH. If the product is
required to
have a specific pH, the overall stability of the C102 could subsequently be
affected. It is
therefore preferred to have the product pH fall within the range of pHs that
promotes the
improved stability.
[0070] Surfactant and other adjuncts
[0071] Surfactant and other adjuncts can be added to the basic
solution to
create a range of products. Surfactants such as Dowfax 3B2 help facilitate
cleaning and
wetting of surfaces to improve the micro efficacy of chlorine dioxide. Gum
thickeners can
be added to thicken the product to improve contact time on a vertical surface
or potentially
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as in a hand sanitizer. For example, gum thickeners may include, but not
limited to,
xanthan gum, Kelzan AP-AS (from CP Kelco), Keltrol (from CP Kelco) or other
suitable
gum thickener. The key is that the adjuncts must be reasonably stable with
chlorine
dioxide. The benefits of proper pH choice also apply to the addition of
adjuncts. We are
not limited to just these two ingredients. Optimizing the pH will improve
stability of formula
containing the desired adjuncts.
[0072] Concentrated Product
[0073]
A concentrated product could have applications such as a floor cleaner,
general cleanerideodorizer, use in toilet bowl, or in laundry applications.
The
concentrated product is a product that may be used full strength or be diluted
prior to use.
The product is prepared using a stabilized formula and then diluted by adding
additional
water or adding the concentrated formula to water. An example of a
concentrated product
and how one is used, is Pine -Sol. You can use Pine -Sol full strength or
dilute it. The
standard calculations ,,,vould apply in terms of dilutions i,e. add product to
an equal amount
of water would dilute it by 50% etc. The concentrate could be a refill for a
spray product.
[0074]
R wok..ild also be possible to make a concentrate two--part product where
the acid and chlorite are separated until they are combined to react.
Since there is no
CO2 produced until acid and chlorite react in a two --part product, the stabty
issues of
CO2 could be avoided,
[0075] The procedure to prepare a C102 concentrate is the same as discussed
above. We would add excess acid to sodium chlorite, and wait for the reaction
to produce
C102 to go to completion. Surfactant could be present either before or after
the reaction
of acid and chlorite. Then we would adjust the pH so that the product in the
range that
provides improved stability. The concentrate is then ready for use.
[0076] The concentration of the chlorine dioxide and the surfactant
would be
higher in the concentrated product to allow for dilution so that the diluted
product will still
have ingredients to be effective. Higher concentration of CO2 may be used to
sanitize
or disinfect while a lower concentration of CO2 in the diluted form
may be good for
general cleaning and deodorizing.
[0077] The concentrated product should be safe to use and have a
suitable
shelf life for storage.
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[0078] In some embodiments the product may include other ingredients,
such
as fragrance, dyes, or thickeners, etc to change the aesthetics or the form of
the product
or even change other performance attributes. In some embodiments gum may he
added
to make a gel product.
[0079] Applications for the Product.
[0080] It is envisioned that the CO2 product disclosed herein may be
used in
many different products depending on the final dilution and concentration.
Uses may
include sanitizer or disinfectant, floor cleaner, general cleaner/deodorizer,
use in toilets,
mouthwash or in laundry applications. The product may be used along or
combined with
other products.
[0081] It is envisioned that the CO2 product be delivered in many
different
forms, depending on the application. Below are some non -limiting examples.
[0082] Sanitizer or Disinfectant ¨ The CO2 product may use many
different
delivery devices depending on the application. For hard surfaces; the CO2
product may
be packaged in a spray bottle or package of wipes. For hand sanitizer, the CO2
product
be in a squirt bottle.
[0083] Floor Cleaner ¨ The CO2 product may be provided in a con
centrated
solution that can be used either at full concentration or diluted, such as
Pine-Sol.
[0084] General cleaner/deodorizer ¨ The CO2 product may be provided in
a
spray bottle, like Lysol, or disinfecting wipes like Clorox Wipes.
[0085] Toilet ¨ The CO2 product m ay be provided in a tablet form to
drop-in
the bowl or put in the toilet tank for each flush, like Clorox tablets. The
tables may be
different concentration, such as the drop-in bowl tablet may have a higher
concentration
than the tank tablet.
[0086] Laundry ¨ The CO2 product may be mixes in a laundry detergent,
or
may be a separate solution additive, like Lysol Laundry Sanitizer Additive, or
as beads
that are thrown in the wash, like Downy Fresh Scent Booster Beads
[0087] In some embodiments the present invention is directed to
improve the
stability of chlorine dioxide (CI02) compositions and products by the proper
choice of pH,
and through the careful choice of other product formula ingredients. By
maximizing the
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stability of chlorine dioxide, the product has a suitable shelf-life and is
ready to use after
manufacturing.
[0088] In some embodiments the device includes a delivery device
configured
to deliver a solution to a target application and a stabilized chlorine
dioxide (C102) product
that is configured to be delivered using the delivery device. The chlorine
dioxide is
produced using a method that includes adding a first amount of Hydrochloric
acid (HCI)
to a second amount of Sodium chlorite (NaCI02) that is dissolved in water, the
first
amount being greater than the second amount; agitating the HCL and NaC102 for
at least
10-15 minutes to mix the chemicals and thus allowing the chemical to react to
completion;
adding a third amount of Dowfax to the solution and slowly agitate the HCI,
NaC102 and
Dowfax solution to distribute the Dowfax; and after the reaction to generate
chlorine
dioxide (C102) in solution has gone to completion, adding a fourth amount of
Sodium
Hydroxide (Na0H) to adjust the pH of the resulting C102 solution to a desired
pH and
concentration.
[0089] In some embodiments the invention is a method of making a high
concentration chlorine dioxide with improved long-term stability comprising.
The method
includes adding 42.61g/I 10% Hydrochloric acid (HCI) to 3.20g/I Sodium
chlorite (NaCI02)
dissolved in water; agitating the HCL and NaC102 for at least 10-15 minutes to
mix the
chemicals; adding 1.50g/I of Dowfax and slowly agitate the HCI, NaC102 and
Dowfax
solution to distribute the Dowfax; and adding 42.23g/I of 5% Sodium Hydroxide
(Na0H)
to adjust the pH of the C102 solution to a desired pH.
[0090] In some embodiments the invention is a method for producing a
high
concentration chlorine dioxide with improved long-term stability. The method
includes 1)
adding a molar excess concentration amount of Hydrochloric acid (HCI) to an
amount of
Sodium chlorite (NaCI02) dissolved in an amount of water; 2) agitating the HCL
and
NaC102 until the reaction to form chlorine dioxide (C102) is complete; 3)
adding an
amount of Dowfax, 4) slowly agitating the HCI, NaC102 and Dowfax solution to
distribute
the Dowfax; and 5) adding an amount of Sodium Hydroxide (Na0H) to the C102
solution
to adjust the pH to a target value; wherein: the molar excess concentration
amount of
acid = 42.61g/I 10% HCI; the amount of sodium chlorite = 3.20g/I NaC102 (80%);
the
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WO 2021/242225 PCT/US2020/034601
amount of Dowfax = 1.50g/I Dowfax, the amount of NaOH =42.23g/I of 5% NaOH;
the pH
target value approximately 4.5 -6.5.
[0091] In some embodiments, the delivery device is a spray bottle and
the
stabilized C102 is a sprayable solution; the delivery device is a wipe and the
stabilized
C102 is a solution integrated into the wipe; the delivery device is a tablet
and the
stabilized C102 is integrated into the tablet; the delivery device delivers a
laundry
detergent and the stabilized C102 is integrated into the laundry detergent;
the delivery
device delivers a deodorizer and the method of producing the C102 further
comprises
adding a fragrance ingredient compatible with CI02; the delivery device is a
cleaning
device and the stabilized C102 is produced as a concentrate that can be used
at full
strength or diluted with water.
[0092] In some embodiments, the desired pH is 4.5 - 6.5, and in other
embodiments the desired pH is 5.91.
[0093] In some embodiments, the C102 is: a sprayable solution
configured to
work with a spray bottle; the C102 is a concentrated solution configured to be
used at full
strength or diluted with water prior to use; the method further comprising
adding a
fragrance ingredient compatible with C102 to produce a fragranced solution.
[0094] It is intended that the specification and examples be
considered as
exemplary only, with a true scope and spirit of the invention being indicated
by the
following claims. In addition, where this application has listed the steps of
a method or
procedure in a specific order, it may be possible, or even expedient in
certain
circumstances, to change the order in which some steps are performed, and it
is intended
that the particular steps of the method or procedure claims set forth
herebelow not be
construed as being order-specific unless such order specificity is expressly
stated in the
claim.
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