Bromate

From Wikipedia, the free encyclopedia
Jump to navigation Jump to search

Template:Short description Script error: No such module "redirect hatnote". <templatestyles src="Chembox/styles.css"/>

Template:Chembox image cellTemplate:Chembox image cellTemplate:Chembox headerbarTemplate:Chembox IndexlistTemplate:Chembox JmolTemplate:Chembox ChEMBLTemplate:Chembox ECHATemplate:Chembox E numberTemplate:Chembox IUPHAR ligandTemplate:Chembox UNIITemplate:Chembox CompToxTemplate:Chembox headerbarTemplate:Chembox ConjugateAcidBaseTemplate:Chembox Datapage checkTemplate:Chembox Footer
Bromate
Template:Longitem Template:Unbulleted list
ChEBI Template:Unbulleted list
ChemSpider Template:Unbulleted list
DrugBank Template:Unbulleted list
EC Number Template:Unbulleted list
Template:Longitem 1888
KEGG Template:Unbulleted list
Template:Longitem Template:Unbulleted list
RTECS number Template:Unbulleted list
UN number 1450
Script error: No such module "collapsible list".
Script error: No such module "collapsible list".
Template:Longitem Template:Chem2
Molar mass Template:Chem molar mass

Template:Chembox Footer/trackingScript error: No such module "TemplatePar".Template:Short description

The bromate anion, Template:Chem2, is a bromine-based oxoanion. A bromate is a chemical compound that contains this ion. Examples of bromates include sodium bromate (Template:Chem2) and potassium bromate (Template:Chem2).

Bromates are formed many different ways in municipal drinking water. The most common is the reaction of ozone and bromide:

BrScript error: No such module "Su". + Template:Chem/link → BrOScript error: No such module "Su".

Electrochemical processes, such as electrolysis of brine without a membrane operating to form hypochlorite, will also produce bromate when bromide ion is present in the brine solution.

Photoactivation (sunlight exposure) will encourage liquid or gaseous bromine to generate bromate in bromide-containing water.

In laboratories bromates can be synthesized by dissolving Template:Chem/link in a concentrated solution of potassium hydroxide (KOH). The following reactions will take place (via the intermediate creation of hypobromite):

Template:Chem/link + 2 OH → BrScript error: No such module "Su". + BrOScript error: No such module "Su". + Template:Chem/link
3 BrOScript error: No such module "Su". → BrOScript error: No such module "Su". + 2 BrScript error: No such module "Su".

Human health issues

Bromate in drinking water is toxic because it is a suspected human carcinogen.[1][2] Its presence in Coca-Cola's Dasani bottled water forced a recall of that product in the UK.[3]

Bromate formation during ozonation

Although few by-products are formed by ozonation, ozone reacts with bromide ions in water to produce bromate. Bromide can be found in sufficient concentrations in fresh water to produce (after ozonation) more than 10 ppb of bromate—the maximum contaminant level established by the USEPA. Proposals to reduce bromate formation include: lowering the water pH below 6.0, limiting the doses of ozone, using an alternate water source with a lower bromide concentration, pretreatment with ammonia, and addition of small concentrations of chloramines prior to ozonation.[4]

Reservoir pollution

File:Ivanhoe Reservoir looking northeast from west side 2015-10-11.jpg
Ivanhoe Reservoir after addition of shade balls

On December 14, 2007, the Los Angeles Department of Water and Power (LADWP) announced that it would drain Silver Lake Reservoir and Elysian Reservoir due to bromate contamination. At the Silver Lake and Elysian reservoirs a combination of bromide from well water, chlorine, and sunlight had formed bromate. The decontamination took 4 months, discharging over Script error: No such module "convert". of contaminated water.[5]

On June 9, 2008 the LADWP began covering the surface of the Script error: No such module "convert"., Script error: No such module "convert". open Ivanhoe Reservoir with black, plastic shade balls to block the sunlight which causes the naturally present bromide to react with the chlorine used in treatment. 3 million of the 40 cent balls are required to cover the Ivanhoe and Elysian reservoirs.[6]

Natural occurrence

Currently no bromate-bearing minerals (i.e., the ones with bromate ion being an essential constituent) are known.[7]

See also

Other bromine anions:

Bromine oxidation state −1 +1 +3 +5 +7
Name bromide hypobromite bromite bromate perbromate
Formula Br BrO Template:Chem/link Template:Chem/link Template:Chem/link
Structure The bromide ion The hypobromite ion The bromite ion The bromate ion The perbromate ion

References

<templatestyles src="Reflist/styles.css" />

  1. Script error: No such module "citation/CS1".
  2. Script error: No such module "Citation/CS1".
  3. Script error: No such module "citation/CS1".
  4. Script error: No such module "Citation/CS1".
  5. Script error: No such module "citation/CS1".Script error: No such module "Unsubst".
  6. Script error: No such module "citation/CS1".
  7. Script error: No such module "citation/CS1".

Script error: No such module "Check for unknown parameters".

Template:Bromates