Optimization of an electrocoagulation unit for purification of ibuprofen from drinking water: Effect of conditions and linear/non-linear isotherm study

ABSTRACT

The present study recommends the electrocoagulation (EC) technique as a possible-green option to the conventional process for the efficient removal of ibuprofen (IBU) from drinking water for the first time, investigating a thorough analysis by optimizing operational parameters and kinetics/isotherms models. Under the optimum conditions 63% of IBU was removed. The double-stage electrocoagulation resulted in the removal efficiency of 73.8%. The dynamic and equilibrium data followed first-order and Freundlich. The treatment cost of IBU removal by electrocoagulation would be 1.8 US $/m3. It is possible to consider the EC technique as the promising IBU removal method.

KEYWORDS:

• Electrocoagulation
• ibuprofen
• pharmaceuticals
• drinking water
• adsorption

Highlights

• Ibuprofen removal was studied by electrocoagulation process.

• Under optimum conditions, maximum removal efficiency of 73.8% was attained.

• Adsorption and precipitation were the dominant ibuprofen removal path.

• Freundlich model was the most suitable one.

Nomenclature

Electrocoagulation	=	EC
Ibuprofen	=	IBU
Electrolyte volume	=	$V_R$(m3)
Electrode area	=	$A_e$(m2)
Mass transfer coefficient	=	$K_m$(m/s)
Reaction time	=	t (s)
Fractional IBU	=	${\mathrm{X}}_{\mathrm{S}\mathrm{B}\mathrm{R}}$
Constant parameters	=	α and y
Double stage electrocoagulation process	=	DSEC
Sips equilibrium	=	KS
Reaction rate constant	=	K1
RP exponent	=	β
Redlich-Peterson	=	RP
RP constants	=	$K_R$ (L/g) and $A_R$ (L/mg)
Freundlich constant	=	${\alpha }_s$ and ${\beta }_s$
Maximum adsorption	=	capacity Qm
Vieth–Sladek constants	=	Kvs and Bvs
Langmuir-Freundlich	=	LF
Langmuir-Freundlich maximum adsorption capacity	=	qMLF (mg/g)
Equilibrium constant for a heterogeneous solid	=	KLF
Heterogeneous parameter	=	MLF
Costs regarding operation	=	Cop
Costs regarding energy	=	Cen,
Costs regarding electrodes	=	Cel

Declaration of interests

The authors declare that they have no known competing interests or personal relationships that could have appeared to influence the work reported in this paper.

Supplementary Material

Supplemental data for this article can be accessed on the publisher’s website.