A Poly(Acrylic Acid)-Based Hydrogel Crosslinked with Hydroxypropylcellulose as a Clarifying Agent in Nickel(II)...

Area of Science:

• Materials Science
• Environmental Science
• Polymer Chemistry

Background:

• Nickel ion (Ni2+) contamination poses significant environmental and health risks.
• Developing efficient and cost-effective materials for heavy metal removal is crucial for water purification.

Purpose of the Study:

• To synthesize and characterize novel crosslinker-free poly(acrylic acid)-hydroxypropylcellulose (PAA-HPC) hydrogels.
• To evaluate the efficiency of these PAA-HPC hydrogels in removing Ni2+ ions from aqueous solutions.
• To assess the reusability of the PAA-HPC hydrogels for Ni2+ ion removal.

Main Methods:

• PAA-HPC hydrogels were synthesized via free radical polymerization in acetone.
• Swelling ratios were measured.
• Ni2+ ion absorption capacity was determined at various concentrations and time points.
• Ni2+ ion release and hydrogel reuse were investigated using HCl solution.
• Absorption mechanism involving chelation and precipitation was analyzed.

Main Results:

• PAA-HPC hydrogels exhibited lower swelling ratios compared to PAA hydrogels synthesized in water.
• High Ni2+ absorption capacities were achieved: 91-340 mg/g (1h) and 122-435 mg/g (24h).
• An average absorption efficiency of 80% was observed, with hydrogels turning green upon Ni2+ uptake.
• Effective Ni2+ release (76.4%) was achieved in HCl, indicating potential for reuse.
• The production cost was approximately $0.2 USD per gram.

Conclusions:

• Crosslinker-free PAA-HPC hydrogels are effective for rapid and efficient removal of Ni2+ ions from contaminated water.
• The PAA-HPC hydrogels demonstrate good reusability, making them a sustainable option for water remediation.
• These findings highlight the potential of PAA-HPC hydrogels as a cost-effective solution for Ni2+ pollution control.