Photocatalytic Processes for the Removal of Dye - Green Chemistry for Dyes Removal from Wastewater - page 121

Table 4.1 Compariso n of Diferent Dye Removal Technologies.

Technology Target Dye Signiicant factors Results Advantages/

Disadvantages

References

Membrane
processes:
reverse
osmosis (RO),
nanoiltration
(NF)

acid red,
reactive
black,
reactive
blue

RO: membrane pore
size (0.5 nm),
operating pressure
(7-100 bars);
NF: membrane pore
size (0.5-2 nm),
operating pressure
(5-40 bars);

i) NF method consumes half
of the electrical power
compared to RO;
ii) NaCl in dye solution
increases dye removal
eiciency;
iii) pH, TDS, applied pressure
and dye concentration
show positive efect on dye
removal;
iv) feed temperature shows
negative efect on dye
removal;

Advantages: higher
removal potential
with lower efective
cost;
Disadvantages:
production of
concentrated
sludge;

(7)

Electro-coagulation reactive

red 198

voltage, electrode
connection mode,
interelectrode
distance,
electrical energy
consumption, dye
concentration
and electrolyte
concentration;

i) dye removal follows irst
order kinetics;
ii) 98.6% dye removal and 84%
COD removal;

Advantages: requires
smaller space,
easy operation,
ecofriendly process,
cost efective
method;
Disadvantages: sludge
generation;

(8)

( Continued )