Open AccessA Simple and Effective Bio-adsorbent Generated from the Stems of Momordica charantia Plant for the Simultaneous Removal of Lead and Cadmium Ions from Wastewater
Author(s) -
Rajesh Babu Vabanagiri,
K. Ravindhranath,
Sneha Latha Pala,
Wondwosen Kebede Biftu
Publication year - 2021
Publication title -
asian journal of chemistry/asian journal of chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.145
H-Index - 34
eISSN - 0975-427X
pISSN - 0970-7077
DOI - 10.14233/ajchem.2021.23345
Subject(s) - chemistry , sorption , adsorption , sorbent , cadmium , biosorption , ion exchange , nuclear chemistry , momordica , effluent , metal ions in aqueous solution , ion , inorganic chemistry , organic chemistry , environmental engineering , medicine , engineering , traditional medicine
Sulphuric acid generated activated carbon from the stems of Momordica charantia (MCSAC) wasidentified to adsorb lead(II) and cadmium(II) ions from water. Extraction conditions were optimized.At pH: 6, both the ions can be simultaneous removed by 2.0 mg/L of MCSAC after an equilibrationperiod of 90 min at room temperate (30 ± 2 ºC). The sorption capacities were observed to be 21.0 mg/gfor Pb2+ and 18.9 mg/g for Cd2+. MCSAC was characterized by conventional methods and also bysurface morphology assessing techniques such as XRD, FTIR and FESEM. The sorption mechanismwas investigated by evaluating thermodynamic parameters and by adopting various kinetic andisothermal models. High ΔH values of 29.399 KJ/mol for Pb2+ and 33.222 KJ/mol for Cd2, indicatedthat the mechanism of sorption is ion exchange and /or complex formation between Pb2+/Cd2+ ions andsurface functional groups present in MCSAC. Further, high positive ΔS values imply the presence ofdisorder at solid-liquid interface, favouring the metal ions to overcome the surface barrier and getadsorbed. The negative ΔG values indicates the spontaneity of sorption process. Spent MCSAC can beregenerated and reused for three cycles. The procedure developed using MCSAC as sorbent wassuccessfully applied to treat real effluents samples collected from several industrial effluents. Thenovelty of the present investigation is that a simple biosorbent is developed for the effective simultaneousremoval of highly toxic Pb2+ and Cd2+ from contaminated water.