PRODUCTS

DBNPA

DBNPA or 2,2-dibromo-3-nitrilopropionamide is a quick-kill biocide that easily hydrolyzes under both acidic and alkaline conditions. It is preferred for its instability in water as it quickly kills and then quickly degrades to form a number of products, depending on the conditions, including ammonia, bromide ions, dibromoacetonitrile, and dibromoacetic acid.DBNPA acts similar to the typical halogen biocides.

CAS NO: 10222-01-2
EC NO: 233-539-7
IUPAC NAMES:
2, 2-Dibromo-3-nitrilopropionamide
2,2 DIBROMO-3-NITRILOPROPIONAMIDE
2,2-Dibrom-3-nitrilpropionamid
2,2-Dibromo-2-cyanoacetamide
2,2-dibromo-2-cyanoacetamide
2,2-dibromo-3-cyanopropanamide
2,2-Dibromo-3-nitrilopropionamide
DBNPA
Dibromo-3-nitrilopropionamide
Dibromocyanoacetamide

SYNOMNYS

2,2-DIBROMO-2-CYANOACETAMIDE;10222-01-2;;2,2-Dibromo-3-nitrilopropionamide;Dbnpa;Acetamide, 2,2-dibromo-2-cyano-;2-Cyano-2,2-dibromoacetamide;XD-7287l Antimicrobial;2,2-Dibromo-2-carbamoylacetonitrile;UNII-7N51QGL6MJ;Dibromocyano acetic acid amide;XD-1603;7N51QGL6MJ;Caswell No. 287AA;NSC 98283;HSDB 6982;Dibromonitrilopropionamide;XD 7287L;EINECS 233-539-7;EPA Pesticide Chemical Code 101801;BRN 1761192;2,2-dibromo-2-cyano-acetamide;Acetamide, 2-cyano-2,2-dibromo-;DBNP;DSSTox_CID_12361;DSSTox_RID_78926;NCIOpen2_006184;DSSTox_GSID_32361;SCHEMBL23129;3-02-00-01641 (Beilstein Handbook Reference);Acetamide,2-dibromo-2-cyano-;ACMC-20980y;2-Cyano-2,2-dibromo-Acetamide;CHEMBL1878278;DTXSID5032361;NSC98283;ZINC1638458;2,2, Dibromo 3-Nitrilopropionamide;2,2-dibromo-3-nitrilopropion amide;Tox21_300089;ANW-14672;MFCD00129791;NSC-98283;SBB008529;2,2-Dibromo-2-cyanoacetamide, 9CI;2, 2-Dibromo-2-carbamoylacetonitrile;2,2-Dibromo-2-cyanoacetamide, 96%;AKOS015833850;2,2-bis(bromanyl)-2-cyano-ethanamide;MCULE-9977107579;NCGC00164203-01;NCGC00164203-02;NCGC00253921-01;AS-12928;SC-22750;CAS-10222-01-2;DB-027512;D2902;FT-0612090;2,2-Dibromo-3-Nitrilo propionamide (DBNPA);22D012;A800546;Q-102771;2,2-Dibrom-3-nitrilpropionamid;2,2-dibromo-3-cyanopropanamide;Slimicide 508;2,2-dibromo-2-cyano-ethanamide;2,2-Dibromo-2-carbamoylacetonitrile;Dibromocyanoacetamide;BE 3S;DBNPA;D-244;DBNPA1;BIOBRO;Busan 94;DBNPA20%;NSC 98283;DBNPA 7287;Mucosin NT;acetamide, 2,2-dibromo-2-cyano-;2,2-bis(bromanyl)-2-cyano-ethanamide;2- cyano-2,2-dibromoacetamide;cyanodibromoacetamide;2,2- dibromo-2-carbamoylacetonitrile;2,2-dibromo-2-cyano-acetamide;2,2-dibromo-2-cyanoacetamide;dibromocyanoacetamide;2 2-Dibromo-3-Nitrilo-Propionamid

DBNPA (2,2, dibromo-3-nitrilo-proprionamide) has the following characteristics:
Compatible with the membrane
* Fast-acting
* Cost-effective
* Acceptable transportation, storage, stability and handling characteristics
* Broad-spectrum control (e.g., planktonic and sessile organisms); algae control is seasonal and situational
* Biodegradable

DBNPA is used in a wide variety of applications. Some examples are papermaking as a preservative in paper coating and slurries. It is also used as slime control on paper machines, and as a biocide in hydraulic fracturing wells and in cooling water.
2,2-Dibromo-2-cyanoacetamide, also known as 2,2-dibromo-3-nitrilopropionamide (DBNPA), can be synthesized reacting sodium bromide and cyanoacetamide. Its crystals are monoclinic and belong to the space group P21/n.
High-performance liquid chromatography analyses of ppm concentrations of DBNPA and its degradation products in laboratory tests of several natural water samples were used to follow the reactions involved. A hydrolysis pathway leads to dibromoacetonitrile (DBAN) and other products. The presence of organic material in the water leads to degradation by a second pathway in which monobromonitrilopropionamide (MBNPA) and several other degradation products are formed. The model describes quantitative relationships of DBNPA dosage and the natural water's organic material content, as measured by total organic carbon (TOC), in the degradation pathways of DBNPA. The model helps interpret the aquatic toxicity of the rapidly changing complex mixture produced during these degradations. Simulations of the DBNPA treatment of cooling towers were compared to limited experimental data which indicated that most of the degradation occurred by the pathway which produced the less toxic products

IDENTIFICATION:

DBNPA is an off-white crystalline solid with a mild medicinal antiseptic odor. It is slightly volatile, very soluble in water, and corrosive.

USE:

DBNPA is used to control bacteria, fungi and slime-forming algae in cooling water systems, evaporative condensers and heat exchangers, air washing systems, pulp mill and paper manufacturing, and oil extraction drilling fluids. It also is used as a preservative in paints, industrial coatings and adhesives, metalworking cutting fluids, and paper and paper products.

The melting point of 125 C. Purity was checked by elemental analysis, infrared analysis [IR (Nujol mull), 1,710 cm (C=O) l, and by nuclear magnetic resonance spectroscopy [NMR (dimethyl sulfoxide ), 8.36 6 (doublet) J.

Physical properties and Chemical properties.

The white, crystalline DBNPA has been stable for at least four years under laboratory storage conditions. This conclusion is based upon no detectable change in appearance or biological activity during this storage period. DBNPA dissolves in water to give a relatively stable solution in an acid pH range. Its unusual solubility and stability in polyethylene glycol (average molecular weight, 200) make this glycol a preferred solvent. Aqueous solutions hydrolyze under alkaline conditions, with the rate of decomposition increases with the alkalinity. However, the rate of hydrolysis is not fast enough to interfere with the antimicrobial activity of fresh, alkaline (pH 7 to 9.5) solutions. Heat and ultraviolet and fluorescent light also cause aqueous solutions of DBNPA to degrade, as evidenced by the change of the antimicrobial endpoint as a given solution age. This ecomposition has also been substantiated by chemical analysis.
It is understood in the membrane industry that thin-film composite polyamide membranes have limited resistance to chlorine-based oxidants. Therefore, operators have relatively few options regarding chemicals that can be safely used to disinfect RO/NF systems and prevent bio growth/biofouling. One option is the chemical, DBNPA, which is a fast-acting, non-oxidizing biocide which is very effective at low concentrations in controlling the growth of aerobic bacteria, anaerobic bacteria, fungi and algae.
DBNPA is an advantageous disinfectant since it also quickly degrades carbon dioxide, ammonia and bromide ion when in an aqueous environment. This allows the effluent to be safely discharged even in sensitive water bodies. It is degraded by reactions with water, nucleophiles, and UV light (rate is dependent on pH and temperature). The approximate half-life is 24 hr @ pH 7,2 hr @ pH 8, 15 min @ pH 9. The vast majority of microorganisms that come into contact with it are killed within 5 to 10 minutes.
DBNPA is deactivated by reducing agents, so a higher concentration of DBNPA will be required if residual reducing agents are present in the feed water. For example, Sodium Bisulfite (SBS) will deactivate DBNPA. If SBS is dosed during service or flushing operations, additional DBNPA will be required at a suggested dose rate of 1.0 to 1.3 ppm DBNPA per 1 ppm of SBS to account for deactivation. Excess SBS can also be used to accelerate the deactivation of DBNPA in discharged waters. Although DBNPA is non-oxidizing, it will give an ORP reading of about 400 mv when in the range of 0.5 – 3 ppm ( for comparison, 1 ppm chlorine typically gives an ORP reading of about 700 mv). Intermittent dosing can be performed during service operation, during a low-pressure flush mode, or by a batch CIP (Clean-In-Place) system. RO/NF permeate may need to be diverted to drain as operations dictate, though it is estimated that greater than 98% of the DBNPA is rejected by brackish water membranes and greater than 99.5% by seawater membranes. For waters containing > 100 CFU/ml (or if you already have biofilm within the RO/NF system), suppliers recommend 30 ppm active ingredient for a full 3 hours. During intermittent dosing, the permeate should be dumped to drain if product water is for potable use. If a biofilm is present, sanitization should be preceded by an alkaline cleaning. For continuous dosing during service operation, between 0.5 to 2 ppm of active ingredient is recommended to maintain a biostatic environment. RO/NF permeate may need to be diverted to drain as operations dictate. Continuous dosing can be significantly more expensive in terms of operating costs so the site situation will dictate if this is instituted. DBNPA is deactivated by reducing agents, so a higher concentration of DBNPA will be required if residual reducing agents are present in the feed water. For example, Sodium Bisulfite (SBS) will deactivate DBNPA. If SBS is dosed during service or flushing operations, additional DBNPA will be required at a suggested dose rate of 1.0 to 1.3 ppm DBNPA per 1 ppm of SBS to account for deactivation. Excess SBS can also be used to accelerate the deactivation of DBNPA in discharged waters. Although DBNPA is non-oxidizing, it will give an ORP reading of about 400 mv when in the range of 0.5 – 3 ppm ( for comparison, 1 ppm chlorine typically gives an ORP reading of about 700 mv). For CIP use, 30 - 50 ppm of active ingredient for 1 hour would be recommended. For heavy biofilms, it should be followed by an alkaline cleaning. Test kits are available from the chemical suppliers to verify that DBNPA is at the desired concentration or has been completely rinsed from the system. According to its chemical properties, DBNPA can be degraded via two pathways; hydrolysis and nucleophilic reaction. For PT 4 nucleophilic reaction is the relevant pathway after DBNPA comes into contact with sulphur containing reducing species (“nucleophiles”), light or organic material (e.g., proteins, bacteria, humus/fulvic acids, etc.). DBNPA will quickly be degraded to cyanoacetamide (CAM). DBNPA is not readily biodegradable. Based on a weight of evidence approach including several studies from the open literature a degradation half-life in soil (DT50) of 20.9 hours at 12oC was used for the risk assessment. In addition, the default value of inherent biodegradable substances was included.
DBNPA has a very low vapor pressure, a low Henry’s law constant and is additionally not used in a manner, which leads to direct release to the atmosphere.
The mixing and loading process takes place in completely closed systems. Thus, the environmental exposure during mixing and loading is considered to be negligible compared to the actual application of DBNPA. The emission estimations for the use of DBNPA in PT4 have been determined using two different scenarios (a tonnage-based scenario and a consumption-based scenario) and a tiered approach. For CAM only the consumption-based scenario, representing the realistic worst case scenario is evaluated
The standard method to apply DBNPA is intermittent dosing. The amount of DBNPA used depends on the severity of the biological fouling. With a waterless prone to biological fouling, using 10 – 30 mg/L of the active ingredient for 30 minutes to 3 hours every 5 days can be effective. Because DBNPA is deactivated by reducing agents (such as sodium bisulfite used for chlorine removal), a higher concentration of DBNPA will be required if there is residual reducing agent in the feedwater. The concentration of DBNPA should be increased by 1 ppm of active ingredient for every ppm of residual reducing agent in the RO feedwater. To remove the dead biofilm, an alkaline cleaning is also recommended . Biocides, their degradation products, and other ingredients in their formulations are not always completely rejected by RO membranes. For this reason, during intermittent dosing, it may be necessary to discharge the permeate during biocide injection because the permeate may contain slightly elevated levels of organics. Note that although DBNPA is nonoxidizing, it does give an ORP response in approximately the 400 mV range at concentrations between 0.5 and 3 mg/L. For comparison, chlorine and bromine give a response in the 700 mV range at 1 mg/L, which increases with

The full name of DBNPA is 2-2-dibromo-3-nitriloproion amide. It is a broad-spectrum and efficient industrial fungicide. DBNPA is used to prevent bacteria and algae from growing in papermaking, industrial circulating cooling water, mechanical lubricants, pulp, wood, paint, and plywood. 2-2-Dibromo-3-Nitrilopropionamide (DBNPA) is currently popular at home and abroad. Organic bromine fungicides.
Sterilization mechanism of DBNPA. DBNPA molecules can rapidly penetrate microbial cell membranes. Act on certain protein groups.

Intended use, target species and effectiveness
DBNPA is intended for use in food processing vessels (e.g. industrial mayonnaise or yogurt producing facilities, fermenters for beer or other fermented products), which are periodically disinfected after use. The disinfection and processing exclusively take place in the industry and only industrial workers may come into contact with DBNPA. DBNPA is a fast-acting biocide and is exerting its biocidal action directly after its application.

DBNPA may be used to control bacteria and reduce biofouling in various membrane system types (reverse osmosis, ultra-filtration, nano-filtration, and microfiltration) used for industrial water processing. Acceptable industrial applications include reverse osmosis systems for the production of boiler make-up water for electric power production, electronic component rinsing, and in the chemical manufacturing industry. DBNPA can also be used for off-line cleaning of RO membranes producing potable and municipal water.

DBNPA has proven efficacy at low concentrations against bacteria, fungi, yeast, cyanobacteria (also referred to as blue-green algae) and true algae. The DBNPA molecule will function immediately upon introduction into the feed water and antimicrobial control is rapidly achieved if properly dosed.

DBNPA offers an advantageous combination of quick kill properties followed by fast chemical degradation, including hydrolysis. The dominant degradation pathway at use conditions involves reactions with nucleophilic substances or organic material invariably
found in water. Nucleophilic degradation forms cyanoacetamide. When the disposal of concentrate involves the release to large open waterways, additional degradation will occur via exposure to UV radiation. When sufficiently diluted, DBNPA and its degradation products become biodegradable. The ultimate degradation products formed from both chemical and biodegradation processes of DBNPA include ammonia, carbon dioxide, and bromide ions.
Therefore, meeting the local environmental regulations for the permitted discharge of the reject stream should not be affected by DBNPA use.

DBNPA product performance
Broad-spectrum, fast and efficient sterilization performance
DBNPA has a broad spectrum of bactericidal properties. It has a good killing effect on bacteria, fungi, yeast, algae, biological slime and pathogenic microorganisms that threaten human health.
Dibromo 3 Nitrilopropionamide (DBNPA) is characterized by extremely fast sterilization and high efficiency. The sterilization rate can reach over 99% in 5-10 minutes. DBNPA was compared to the other three biocides. The results showed that when the same bactericidal effect was achieved, DBNPA was used at a dose of only 7.5ppm, which is much lower than the other three fungicides.
Good inhibition of peeling on biofilms. When DBNPA is added to the system, its active components act rapidly on planktonic microorganisms. It can be quickly sterilized. At the same time, the permeability of organic bromine is good. The active component of the agent rapidly penetrates the metal surface. Acts on smaller microbial communities. It allows rapid depolymerization and prevents the formation of biofilms.
For systems that have formed biofilms, the active components do not react with the slime layers in the biofilm. It quickly penetrates deeper into the biofilm. A microbial community acting at the junction of a biofilm and a metal surface. Destruction of its viscosity causes the biofilm to fall off.
Experimental studies have shown that for the peeling of the biofilm at the age of 7 days, the smaller dosage can achieve the same peeling effect, and the advantage of the peeling effect on the biofilm is very obvious.

Effectively kill Legionella
DBNPA on Legionella is very significant. Studies have shown that 2-5mg/L DBNPA (effective), can reduce Legionella 5-6 logs within 3 hours. 2-4 mg/L DBNPA (effective) can reduce Legionella by 6 logs for 2 hours. For Legionella in biofilms. 10mg/L DBNPA (effective), 12 hours can completely kill Legionella. Additional data indicate that low doses of organic bromine and glutaraldehyde are used in combination. Legionella in biofilms can be lowered to undetectable levels.
Rapid degradation
DBNPA is rapidly degraded to carbon dioxide, ammonia and bromine salts upon completion of bactericidal action. It does not cause the enrichment of harmful ions in the water. There is no impact on the environment, so emissions are not restricted. This is a distinguishing feature of organic bromine biocides that distinguishes them from other non-oxidizing biocides.

Effectively kill sulfate-reducing bacteria
The oilfield sewage has a high sulfate content, which is very beneficial to the reproduction of sulfate-reducing bacteria. The large-scale reproduction of sulfate-reducing bacteria will lead to an increase in the content of H2S in water. 2 2 Dibromo 3 Nitrilopropionamide (DBNPA) acts rapidly on sulfate-reducing bacteria. It can be quickly killed before it reacts with sulfate to form H2S.
Experimental studies have shown that 10 mg/L can effectively control the sulfate-reducing bacteria in the system, so as to completely remove the sulfide in the re-injection system and protect the system from sulfide corrosion.

DBNPA application area
DBNPA is widely used as a disinfectant, bactericide, algicide, slime stripper, and mildew inhibitor in the following aspects.
The circulating cooling water system, oil field water injection system, bactericide, algicide, slime stripper in the paper industry.
Preservatives for paints, waxes, inks, detergents, surfactants, slurries, resins.
Process water, air purifier system in the machinery manufacturing industry, fungicides, and algicides in municipal water landscapes.

DBNPA usage
When used as a water treatment slime stripper, the DBNPA is added at a concentration of 30-50 mg/L.
Used as a water treatment bactericide for circulating cooling water systems. According to water retention, DBNPA is added at 10-20 mg/L.

DBNPA is also used in the process of papermaking to prevent reducing the quality of paper by a generation of microorganisms.
It is suitable for metal cutting of cooling liquor, recovery system of oil, latex, and ply-woods as anti-spy biocides. DBNPA has the following advantages.
-Easy to handle.
-No unusual oxidation hazards.
-Similar performance and safety in paper and oilfield applications.
-Slime control in the wet-end of the paper mill and performs exceptionally well against slime-forming bacteria.
-DBNPA has exhibited outstanding efficiency in bio-films and against a broad spectrum of bacteria, fungus, and yeasts.
-Additionally, DBNPA series products are used in the short-term preservation of coatings and coating additives. Such as latex, starch and mineral slurries. It is a quick-kill biocide that is broad-spectrum and does not contain or release formaldehyde.

DBNPA is used as a non-oxidizing bactericide. In combination with bromine-based bactericides under frequent leakage conditions, the microbial control of the system can be improved. The specific plan is as follows.

Microbial control effect:
Under the harsh water quality conditions of the refinery system, DBNPA works synergistically with the bromine-based bactericide to better control the microorganisms. It has a good peeling performance in a system where biological slime breeds severely. After the system uses DBNPA biocide, the cooling tower packing and tower wall are clean, and no sticky mud algae breeds. DBNPA contributes to the maintenance of residual chlorine in bromine-based bactericides.

DBNPA Usage
1. It is a broad-spectrum and high-efficiency industrial fungicide used to prevent the growth of bacteria and algae in papermaking, industrial circulating cooling water, metalworking lubricants, pulp, wood, paint and plywood.
2. It can quickly penetrate the cell membrane of microorganisms and act on a certain protein group to stop the normal redox of cells and cause cell death.
3. Its branches can also selectively bromine or oxidize specific enzyme metabolites of microorganisms, ultimately leading to microbial death.
4. This product has good peeling performance, no foam, and its liquid products and water can be dissolved at any ratio.

The biocide 2,2-dibromo-3-nitrilopropionamide (DBNPA) is the second most commonly used biocide in UOG after glutaraldehyde. DBNPA is a fast-acting electrophilic biocide; it is quick and effective in contact, but the protection is not long-lasting. This biocide inhibits essential biological functions by reacting with nucleophiles (particularly sulfur-containing nucleophiles) inside the cell. DBNPA, and some of its degradation products, can also be harmful to humans and animals. These associated compounds have been demonstrated to be moderate to highly toxic by ingestion and inhalation, can be corrosive to eyes, and have been shown in terrestrial and aquatic animal studies to cause developmental issues.

DBNPA is not toxic to all life, however, as it is biodegradable under both aerobic and anaerobic conditions, with a reported biotic half-life of less than 4 h under both conditions at neutral pH. However, the hydrolysis and aquatic photolysis half-life of this compound are pH-dependent, with faster degradation occurring at a more alkaline pH. For example, the abiotic half-lives of DBNPA at pH 5, 7, and 9 are 67 days, 63 h, and 73 min, respectively. Conversely, low pH has been characteristic of HF-impacted streams, which thus provide favorable conditions for the stability of DBNPA and its degradation products.

DBNPA is a non-oxidative agent, rapidly degrading in alkaline aqueous solutions. The organic water content, as well as light, enhances the hydrolysis and debromination of DBNPA into cyanoacetamide followed by degradation into cyanoacetic acid and malonic acid, which are non-toxic compounds. This degradation pathway makes the use of DBNPA relatively environmentally friendly. DBNPA is compatible with polyamide-based membranes and shows high rejection rates for RO membranes. The antimicrobial effect is due to the fast reaction between DBNPA and sulfur-containing organic molecules in microorganisms such as glutathione or cysteine. The properties of microbial cell-surface components are irreversibly altered, interrupting the transport of compounds across the membrane of the bacterial cell and inhibiting key biological processes of the bacteria.

Broad Spectrum Non-Oxidising Biocide:
Active Ingredients: min 98% 2,2-Dibromo-3-NitriloPropionamide (DBNPA) assay Highly effective against a wide range of common water-borne organisms with proven efficacy against Legionella. Accepta 6404 will control these organisms and help to control microbiological fouling.

Compatibility with other water treatment chemicals and water conditions: DBNPA is compatible with other treatment chemicals with the exception of mercaptobenzothiazole. It also is not compatible with ammonia or hydrogen sulfide-containing water. DBNPA maintains reliable control in systems running at acidic, neutral, or alkaline pH.
Degradation in water: DBNPA degrades quickly in aqueous environments. At neutral pH, its half-life is about nine hours. Continuous biocide release by the tablet maintains concentrations effective for control in the tower, while the biocide in the blowdown discharge degrades quickly. So it’s easy to meet strict environmental regulations on tower discharge.
Is DBNPA an oxidizer?
DBNPA is not an oxidizing biocide and it is not a bromine release biocide. DBNPA does act similar to the typical halogen biocides.
DBNPA is a biocide used in a variety of industrial processes to control algae, bacteria, fungi and yeasts. Formulations include tablets and both solid and liquid soluble concentrates. DBNPA is applied through intermittent, initial, intermittent, maintenance, during manufacture and continuous feed treatments, using metering pumps, drip-feed devices and other types of industrial equipment. A National Pollutant Discharge Elimination System (NPDES) permit is required for discharges to waterways.
DBNPA is a highly effective, environmentally friendly biocide. It provides a quick kill while also quickly degrading in water. The final end product is carbon dioxide and ammonium bromide.
Compatibility with other water treatment chemicals and water conditions: DBNPA is compatible with other treatment chemicals with the exception of mercaptobenzothiazole. It also is not compatible with ammonia or hydrogen sulfide-containing water. DBNPA maintains reliable control in systems running at acidic, neutral, or alkaline pH.

The Koc of DBNPA is estimated as 58(SRC), using a log Kow of 0.80 and a regression-derived equation. According to a classification scheme, this estimated Koc value suggests that DBNPA is expected to have high mobility in soil.
The Henry's Law constant for DBNPA is estimated as 1.9X10-8 atm-cu m/mole(SRC) derived from its vapor pressure, 9.0X10-4 mm Hg, and water solubility, 1.5X10+4 mg/L. This Henry's Law constant indicates that DBNPA is expected to be essentially nonvolatile from water surfaces. DBNPA's estimated Henry's Law constant indicates that volatilization from moist soil surfaces is not expected to occur(SRC). DBNPA is not expected to volatilize from dry soil surfaces(SRC) based upon its vapor pressure.
The disappearance of DBNPA at 50 ppm in soil was more rapid than when present in an aqueous solution at a similar pH. Degradation in 7 soils was measured; half-lives of 4, 12, 15, 15, 6, 25, and 15 hours were reported for a sandy loam (pH 7.5), loam (pH 4.8), silty loam (pH 5.8), sandy loam (pH 6.5), loamy sand (pH 5.8), silty clay loam (pH 5.1), and loam (pH 4.8) soil, respectively. DBNPA has a half-life of fewer than 4 hours in anaerobic aquatic metabolism study. Dibromoacetic acid (reached 66% of applied at 0 hours, 9% at hour 5) and 2-cyanoacetamide (reached 56.5% of applied at hour 5, 2.3% at day 30) were the major degradates. Other degradates include oxalic acid, bromoacetic acid, bromoacetate, and dibromoacetonitrile. Oxalic acid, 2-cyanoacetamide (16% by day 2) and bromoacetamide (2% by day 2) were found in the sediment layer. DBNPA, present at 100 mg/L, reached 0% of its theoretical BOD in 4 weeks using an activated sludge inoculum at 30 mg/L in the Japanese MITI test classifying the compound as not readily biodegradable. Microbial degradation of DBNPA has been demonstrated by the use of tracer techniques (14C-radiolabeled) which yielded 40% 14-CO2 after two weeks in the presence of waste treatment sludge.
2,2-Dibromo-3-nitilopropionamide has a half-life of fewer than 4 hours in an anaerobic aquatic metabolism study; residues were mainly found in the aqueous layer. Concentrations of the two main degradates 2-cyanoacetamide (reached 56% of applied within 7 days) and dibromoacetic acid (reached 27% of applied at 0 hr, 17% by day 48) were measured. Other minor degradates include oxalic acid, bromoacetamide and dibromoactonitrile. 2-Cyanoacetamide, dibromoacetonitrile and bromoacetamide were found in the sediment layer. The anaerobic metabolism study includes degradation due to both biotic and abiotic mechanisms.
The rate constant for the vapor-phase reaction of DBNPA with photochemically-produced hydroxyl radicals has been estimated as 2.0X10-12 cu cm/molecule-sec at 25 °C(SRC) using a structure estimation method. This corresponds to an atmospheric half-life of about 8 days at an atmospheric concentration of 5X10+5 hydroxyl radicals per cu cm. Less than 1% of a 4000 ppm aqueous solution of DBNPA remained after 28 days exposure to sunlight; 91% of the added DBNPA was still present in the dark control after the same period of time. Dibromoacetic acid (63.7%) is the major degradate at pH 5 (half-life of 14.8 hours; dark control forms dibromoacetic acid at 38.6%) and at pH 7 (half-life of 6.9 hours; dark control forms dibromoacetic acid at 74.9%) in aqueous photolysis studies. Hydrolysis half-lives of 155, 8.8, 5.8, 2.0, and 0.34 hours were measured at pH values of 6.0, 7.3, 7.7, 8.0, and 8.9, respectively. The half-life of DBNPA is 67 days at pH 5, 63 hours at pH 7, and 73 minutes at pH 9. Dibromoacetic acid (30.6% of applied), dibromoacetonitrile (54.5% of applied), and dibromoacetonitrile (38.6% of applied) are the major degradates at pH values of 5, 7, and 9, respectively.
DBNPA's production and use as a bactericide and algicide in commercial water cooling and treatment systems and paper-pulp mill water systems may result in its release to the environment through various waste streams(SRC).
Based on a classification scheme, an estimated Koc value of 58(SRC), determined from a log Kow of 0.80 and a regression-derived equation, indicates that DBNPA is not expected to adsorb to suspended solids and sediment(SRC). Volatilization from water surfaces is not expected based upon an estimated Henry's Law constant of 1.9X10-8 atm-cu m/mole(SRC), determined from its vapor pressure, 9.0X10-4 mm Hg and water solubility, 1.5X10+4 mg/L. According to a classification scheme, an estimated BCF of 3(SRC), from its log Kow and a regression-derived equation, suggests the potential for bioconcentration in aquatic organisms is low(SRC). Degradation in water is due to both abiotic and biotic processes. Hydrolysis half-lives of 67 days, 63 hours, and 73 minutes were measured for DBNPA at pH 5, 7, and 9, respectively. Dibromoacetic acid is the major degradate at pH 5 while dibromoacetonitrile is the major degradate at pH values of 7 and 9. The half-life of DBNPA is less than 4 hours in anaerobic and aerobic metabolism studies. Degradates include oxalic acid, 2-cyanoacetamide, bromoacetamide, dibromoacetic acid, bromoacetic acid, and dibromoacetonitrile; the concentration of each degradate over time varies with the oxygen condition. DBNPA is susceptible to photodegradation in water; <1% of initial DBNPA remained after exposure to sunlight for 28 days. Sunlight degrades DBNPA in water at rates that become relatively fast compared to hydrolysis at pH less than 5.
According to a model of gas/particle partitioning of semivolatile organic compounds in the atmosphere, DBNPA, which has a vapor pressure of 9X10-4 mm Hg at 25 °C, will exist solely as a vapor in the ambient atmosphere. Vapor-phase DBNPA is degraded in the atmosphere by reaction with photochemically-produced hydroxyl radicals(SRC); the half-life for this reaction in air is estimated to be 8 days(SRC), calculated from its rate constant of 2.0X10-12 cu cm/molecule-sec at 25 °C(SRC) determined using a structure estimation method. Based on photolysis studies showing degradation in aqueous solution exposed to sunlight (99% loss in 28 days), DBNPA is expected to be susceptible to direct photolysis in the atmosphere(SRC).

The application of the compacted DBNPA, has several advantages:
a) Use of a concentrated solid biocide (>95 wt % active material), and the avoidance of an organic solvent which is required as a co-solvent to prepare an aqueous formulation.
b) Simplification of operation and minimization of handling, resulted in less exposure of the user to the harmful biocide.
c) Increased logistic efficiency and minimization of environmental pollution.
According to the invention, it has been found that powdered DBNPA (such as 98 wt % active material) can be compacted in a dry-process, without the addition of a binder, to yield a product in either a tablet and/or a granular and/or a briquette and/or a pellet form.
According to the invention, the process for compacting powdered DBNPA provides high quality tablets at a moderate pressure of 1300 kg/cm2. More specifically, the process is characterized in that DBNPA is compressed with a pressure of at least 500 kg/cm2, to yield a compacted DBNPA pellet or tablet. Preferably, the pressure employed is between about 1000 and 2000 kg/cm2. Thus, for instance, the density obtained under a compaction pressure of 1500 kg/cm2 (2.1 g/cm3) is 88% of the theoretical density of DBNPA.
Preferred compacted biocidal products of the present invention, are those comprising at least 97% (by wt) DBNPA, and between 0 and about 3% (by wt) of water and/or inert ingredient.
The following examples are provided merely to illustrate the invention and are not intended to limit the scope of the invention in any manner.

2,2-Dibromo-3-nitrilopropionamide (DBNPA) is a biocide which is used in industrial water treatment, cooling systems and paper mills. DBNPA is an efficient biocide with a rapid microbiocidal broad-spectrum activity, especially in water systems that contain high organic loads.
The main current application of DBNPA is as a liquid formulation, which contains a mixture of water and an organic solvent such as a glycol (for example, polyethylene glycol (PEG), dipropylene glycol (DPG), ethylene glycol, etc.) and others. The active ingredient (DBNPA) is only 5-25% of such liquid formulation. The addition of an organic solvent is required for dissolution of the relatively water-insoluble DBNPA into a liquid formulation.
Prior art teaches the production of DBNPA as a powdered material which can be used for the preparation of a liquid or solid formulation.

Several types of sustained-release compositions containing DBNPA have been described:
1) EP 285 209 recites a solid sustained release antimicrobial composition (in a tablet form), comprising 1 to 90% by wt of a halogenated amide (including DBNPA) antimicrobial agent, 10 to 80% by wt of a hydrophilic polymer, 0 to 80% by wt of a compression agent and 0 to 10% by wt of a mold release agent. A composition comprising 40% DBNPA, 30% Methocel (water soluble cellulose polymer), 27% CaHPO4 (as compressing agent) and 3% stearic acid, was specifically demonstrated.
2) WO 98/25458 discloses a solid sustained-release tablet consisting of DBNPA admixed with a water-soluble natural or synthetic polymer. Besides the addition of a synthetic polymer into the formulation, the tablet is coated with an additional water-soluble cellulosic polymer.
3) WO 99/18162 discloses a biocidal powder coating composition comprising thermoplastic and/or thermosetting resins based on epoxy, polyester, acrylic or polyurethane resins. The biocide used is a liquid bio-active material (including DBNPA) and/or specially selected solid bio-active materials (for example, solid thiazine-thiones, thiolphthalimides, and others). The biocides are homogeneously mixed or bonded with the particles of the powder.
The process of preparing said biocidal powder coating composition is characterized by blending the components of the powder coating composition in a premixer, followed by feeding the mixture into an extruder, heating to a temperature high enough to melt and mix most of the major components, and cooling to a solid form.
4) EP 953 284 discloses a composition (in a tablet form) for delivering the DBNPA biocide to an oil field fracturing fluid, comprising effervescing agents such as sodium bicarbonate, citric acid and borax. The composition comprises about 35-65% DBNPA, about 15-28% sodium carbonate, 15-27% citric acid and up to about 20% borax.
5) EP 954 966 recites controlled release compositions comprising a biologically active compound, including DBNPA, and a hydroxy styrene polymer (e.g. hydroxystyrene homopolymer, methylhydroxystyrene homopolymer, halohydroxystyrene homopolymer and their copolymers). The weight ratio of DBNPA to the polymer is from 0.1:99.9 to 95:5.
The above prior art is related to sustained-release formulations (including in a tablet form) which contain various additives, such as polymeric matrix, binders and compression agents insignificant amount. However, no free DBNPA compound in a compacted form has been used and/or described in the literature. The ability to provide an almost net content of the active compacted material (such as in a tablet, granule, pellet or briquette form) is most certainly a significant advantage.

The handling of the existing DBNPA powdered solid material requires severe safety precautions due to the hazardous nature of this biocide, especially in a fine powdered form.
An additional problem concerning the application of powdered DBNPA, is the tendency of the powder to agglomerate, creating lumps and bulky material. This phenomenon reduces the flowability of the product and causes handling and safety problems.

In view of these disadvantages of powdered DBNPA, there is a need for a safer, easy to handle and user-friendly densified particulate DBNPA. Such DBNPA should be free of said agglomeration phenomena. As was mentioned above, the densified forms known in the art have the considerable drawback of requiring the addition of binders and fillers to obtain suitable solid forms of the biocide. Therefore, compacted forms known in the art do not provide net or almost net contents of active material in the tablet, granule, briquette, or pellet form. It has now been found that it is possible to prepare compacted forms of DBNPA that have sufficient strength and provide a slow release of the active material into the water without losing their compacted nature. It has further been surprisingly found that it is possible to prepare compacted forms of this biocide, without employing any binder or filler.
An important environmental feature of DBNPA. High-performance liquid chromatography analyses of ppm concentrations of DBNPA and its degradation products in laboratory tests of several natural water samples were used to follow the reactions involved. A hydrolysis pathway leads to dibromoacetonitrile (DBAN) and other products. The presence of organic material in the water leads to degradation by a second pathway in which monobromonitrilopropionamide (MBNPA) and several other degradation products are formed. The model describes quantitative relationships of DBNPA dosage and the natural water's organic material content, as measured by total organic carbon (TOC), in the degradation pathways of DBNPA.
DBNPA or 2,2-dibromo-3-nitrilopropionamide is a quick-kill biocide that easily hydrolyzes under both acidic and alkaline conditions. It is preferred for its instability in water as it quickly kills and then quickly degrades to form a number of products, depending on the conditions, including ammonia, bromide ions, dibromoacetonitrile, and dibromoacetic acid. DBNPA acts similar to the typical halogen biocides.
DBNPA is used in a wide variety of applications. Some examples are in papermaking as a preservative in paper coating and slurries. It is also used as slime control on paper machines, and as a biocide in hydraulic fracturing wells and in cooling water.
DBNPA 99% is a fast-acting, non-oxiziding biocide. It has outstanding environmental properties because it is non-persistent and degrades to naturally occurring products. DBNPA 99% provides efficient, cost-effective microbiological control at low use concentrations.

Product Benefits
1. Able to eradicate a wide range of microbes (fungal, bacterial, algal)
2. Minimizes production downtime and delays due to contamination
3. Environmentally friendly
4. Handling ease
5. Does not contribute problematic components to
6. formulations or create long term health and safety concerns
Usage: For water treatment agents, bactericidal algaecides, paper pulp, and pharmaceutical intermediates
Use range: It is mainly used as a bactericidal algaecide to prevent bacteria and algae from growing in paper industry water, industrial cooling water, air conditioning water, metalworking lubricants, water emulsions, pulp, wood, plywood and coatings, and fibers.

Precautions:
The aqueous solution is relatively stable under acidic conditions and is easily hydrolyzed under alkaline conditions. Raising the pH, heating, and irradiating with ultraviolet or fluorescent light can greatly increase the dissolution rate. Easy to be deoxidized by reducing agents such as hydrogen sulfide to become non-toxic amines of cyanoacetic acid, greatly reducing the bactericidal rate.
Formulations comprised of DBNPA and organic solvents contribute more chemical oxygen demand than if DBNPA is employed alone or with non-organic solvents because organic solvents serve as a feeding ground for microorganisms by providing nutrients. Therefore, even though the DBNPA may destroy a majority of the microorganisms before it degrades, a few microorganisms still survive. Those few microorganisms multiply very rapidly in the presence of an organic solvent. Therefore, when DBNPA-treated waste water containing an organic solvent is released to the environment, or even if it is in a closed system, chemical oxygen demand will increase significantly over time due to the rapidly multiplying microorganisms consuming oxygen in the water.
It would be desirable to discover liquid formulations of DBNPA that utilize water as a suspending medium and in which the DBNPA is protected to prevent or reduce the decomposition or degradation thereof. This type of formulation would not only reduce the chemical oxygen demand as compared to the present commercial formulations which employ polyalkylene glycols, but such a formulation would also be less expensive. It would also be advantageous if a wide range of concentrations of DBNPA could be employed in the formulations.

Properties:
White crystals. The melting point of 125℃, it can soluble in common organic solvents (such as acetone, benzene, dimethylformamide, ethanol, polyethylene glycol, etc.), slightly soluble in water (25 ℃, 100g water dissolved 1.5g). Its aqueous solution is more stable under acidic conditions and easy hydrolysis in alkaline conditions. Increasing the pH value, heating with an ultraviolet light or fluorescent light can make its dissolution rate greatly accelerated. Easy to be reductant, such as hydrogen bromide and bromine into non-toxic cyanide acetamide, the sterilization rate greatly reduced. When its pH value increases from 6.7 to 9.7, the half-life will change from 37.0h into 0.11h.

Usage:
It is used as an anti-microbial agent, controlling bacterial, fungal and algal growth in industrial water systems like cooling towers, pulp and paper mill process water, oil-recovery systems and air-conditioning systems.
It is a chemical additive to control bacterial contamination in ethanol fermentation.
DBNPA (also 2,2-dibromo-3-nitrilopropionamide) is a white to yellow powder which can be used as a quick-kill biocide to control slime and microbial fouling in oil well, water treatment, paper mill and other industries. DBNPA biocide can easily be hydrolyzed under both alkaline and acidic conditions and quickly kill microorganisms. After that, DBNPA will be degraded to ammonia and bromide ion. It is an excellent combination of rapid degradation and faster microbial kill at low ppm concentrations. DBNPA biocide can also be effectively combined with glutaraldehyde solution to control the microbial growth in cooling water systems.

Usages:
DBNPA based antimicrobial product applications:
♦Enhanced oil recovery systems
♦Pulp & paper mills
♦Cooling systems like recirculating cooling towers
♦Heat exchangers
♦Industrial water-purification like reverse osmosis (RO)
♦Evaporative condensers
♦Sewage systems

DBNPA is an active ingredient (98%) that can be used to prepare fast-acting, efficient biocides for controlling microbial, fungal and algal growth in industrial water systems such as cooling towers, pulp and paper mill process water, oil-recovery systems, metal-cutting coolants, and air-conditioning systems.
DBNPA is a manufacturing use pesticide used in formulating microbiocidal bactericides. End-use formulations are used to control microbial, fungal and algal growth in industrial water systems such as cooling towers, evaporative condensers, pulp and paper mill effluents, oil-recovery systems, metal-cutting coolants, air-conditioning systems (effective against Legionella).

Description:
2,2-Dibromo-2-cyanoacetamide DBNPA 2,2-Dibromo-3-Nitrilopropion Amide is a fast-kill biocide that will hydrolyze very easily under both acidic and alkaline conditions. This product is warmly welcomed because of for its instability property in water. 2,2-Dibromo-2-cyanoacetamide DBNPA 2,2-Dibromo-3-Nitrilopropion Amide will kill bacterial and then quickly degrades to form a number of chemicals. This substance works just like the typical halogen biocides.
2,2-Dibromo-2-cyanoacetamide DBNPA 2,2-Dibromo-3-Nitrilopropion Amide is utilized in many areas. For example, it found its application in papermaking as a preservative in paper coating and slurries. 2,2-Dibromo-2-cyanoacetamide DBNPA 2,2-Dibromo-3-Nitrilopropion Amide is also applied as slime control on paper machines, and as a biocide in hydraulic fracturing wells and in cooling water.
DBNPA is used in formulating biocides. It is used as a preservative for coatings, slurries and to control microbial fouling in paper mills, oil fields and leather processes. It is used in the water treatment process.
DBNPA 2,2-dibromo-3-nitrilopropionamide CAS 10222-01-2 is a quick-kill biocide that easily hydrolyzes under both acidic and alkaline conditions. DBNPA is white crystalline powder, melting point, 122-125℃, PH value, 5--5.5. DBNPA is soluble in common organic solvents (such as acetone, benzene, dimethylformamide, ethanol, polyethylene glycol, etc.), slightly soluble in water. Under acidic conditions, its aqueous solution is more stable. Raising the PH, heating or being exposed to UV and fluorescent light can fasten its dissolving. DBNPA is used in a wide variety of applications. Some examples are papermaking as a preservative in paper coating and slurries. It is also used as slime control on paper machines, and as a biocide in hydraulic fracturing wells and in cooling water.