AMD and gold cyanidation

Question 1

what happens during the chemical rxn for the oxidation of pyrite

Answer 1

produces loos H+ ions with acidifies then the environment
a yellow by-product called ferric hydroxide is produced

Question 2

what types of rocks is pyrite found in

Answer 2

metamorphic, specifically shales that are interbedded within coal seams
common near coastal swamps

Question 3

how do microbes influence the oxidation of pyrite

Answer 3

they catalyze the oxidation process
they convert metals into their soluble state

Question 4

what are treatments for AMD

Answer 4

adding a buffer to water systems (fresh)
limit areas of exposed rock which can oxidize
compacting the rock so its smaller
cover the rock with sealing layers

Question 5

what does cyanide do during gold extraction

Answer 5

used to separate cold from other compounds, commonly silver

Question 6

what happened at Baia mare romania?

Answer 6

large cyanide leak from gold mining into the Somes River
killed many fish (main food source)
worst spill since Chernobyl

Question 7

what is the most common oxidation agent

Answer 7

O2, when compounds contact the atmosphere

Question 8

what sort of scale is the pH built on

Answer 8

logarithmic
small change on scale e means big change in H+ count

Question 9

where are acidic soils found?

Answer 9

jungles and rainforests

Question 10

where are basic soils found?

Answer 10

deserts

Question 11

how does rain impact soil pH?

Answer 11

H2O combines with CO2 in the atmos to form carbonic acid (weak 5.5) and has the ability to reduce to the soil pH

Question 12

what is the common ph of plants

Answer 12

slightly acidic- 5.5-7

Question 13

what is gossan

Answer 13

the rusty exposure of a rock

Question 14

what is the rusty exposure of a rock?

Answer 14

gossan

Question 15

how is AMD preventable

Answer 15

prevent or delay oxidation

bacteria inhibition
desulfurization (prevent the formation of SO2)
physical barrier
chemical barrier

Question 16

limitations of physical barriers

Answer 16

expensive
effective for only a short term
generate a lot of waste

Question 17

limitations of bactericides for AMD

Answer 17

short effective period and only work on fresh tilling sites
commonly toxic fro aquiatic envrion

Question 18

how does AMD impact health

Answer 18

degradation of habitiats and intoxicate food sources

Question 19

what are treatments for AMD

Answer 19

adding a buffer to water systems (fresh)
limit areas of exposed rock that can oxidize
compacting the rock so its smaller
cover the rock with sealing layers

Question 20

how does cyanide interfere with cell function

Answer 20

prevents the cells from using oxygen and leads to depression of the NS and respiratory arrest

Question 21

what are the impurities of the gold smelting process called

Answer 21

slag