Rajith Perera

@article{Perera2025c,

title = {Enhanced adsorption of MCPA pesticide using a novel sand/graphene oxide composite},

author = {WPRT Perera and PLRA Perera and NMN Ruwanthi and AVAP Vitharama and Amila Kannangara and JA Liyanage and AR Kumarasinghe},

url = {https://rajithperera.com/wp-content/uploads/2025/11/68b52d739c34a.pdf},

doi = {10.4038/jmtr.v10i1.77},

year  = {2025},

date = {2025-09-01},

journal = {Journal of Multidisciplinary & Translational Research},

volume = {10},

issue = {1},

pages = {10-24},

abstract = {Developing graphene-based composites for mitigating water pollutants is crucial, as current composites often have limitations, including their specific adsorption behavior towards only one type of contaminant. Additionally, these existing composites are associated with high costs, challenging recovery processes, and potential toxicity to both the environment and human health. Multiple coated sand/graphene oxide composites (M-GO/S) present a promising solution to these challenges. In this study, we focused on investigating the adsorptive removal of the pesticide 2-methyl-4-chlorophenoxyacetic acid (MCPA) using M-GO/S composites. Additionally, we aimed to elucidate the underlying adsorption mechanism and develop an HPLC method for analyzing MCPA. The retention time for MCPA was determined to be 1.538 minutes. The optimal parameters for MCPA adsorption onto M-GO/S were established as a 75 mg/L MCPA concentration, a dosage of 0.05 g, and a contact period of 105 minutes at neutral pH. The isotherm studies indicate that it is challenging to distinctly classify the adsorption process using the Langmuir and Freundlich models, as they show similar R2 values. This may be attributed to the likely occurrence of multilayered attachment of MCPA following an initial monolayer adsorption. The adsorption intensity (n) value of 0.625 further suggests that complex interactions are involved in MCPA adsorption, likely due to the surface complexity of the M-GO/S composite. Apart from that, the kinetics studies revealed that the rate-controlling step involves chemical adsorption between the surface of M-GO/S and MCPA. Chemical interactions arise through hydrogen bonding and critical interactions between the hydroxyl groups on M-GO/S and the aromatic rings of MCPA. M-GO/S is a promising candidate for the adsorptive removal of negatively charged pesticide molecules like MCPA. It outperforms activated carbon and sand in effectiveness, and it is more advantageous than graphene oxide due to its simple recovery process},

keywords = {Adsorption, Adsorptive removal, Graphene oxide, MCPA, Pesticide, Sand},

pubstate = {published},

tppubtype = {article}

}

@article{Alwis2025,

title = {Calamondin Peel Waste-Derived Activated Carbon as a Biosorbent for Heavy Metal Removal from Aqueous Solutions},

author = {DS. Alwis and PLRA Perera and C. S. K. Rajapakse},

url = {https://rajithperera.com/wp-content/uploads/2025/06/021-339201713-17192025.pdf},

doi = {10.14233/ajchem.2025.33920},

issn = {0970-7077},

year  = {2025},

date = {2025-06-30},

urldate = {2025-06-30},

journal = { Asian Journal of Chemistry },

volume = {37 },

issue = {7 (2025)},

pages = {1713 - 1719},

abstract = {This research focused on utilizing agricultural waste, calamondin (Citrus madurensis) peel, to produce low-cost calamondin peel-based activated carbon (CPAC), initially for Pb(II) ion removal from simulated water. CPAC, prepared by carbonizing chemically treated peel waste at 400 ºC for 120 min, achieved 99% Pb(II) removal under optimized conditions: 5 ppm initial Pb(II) concentration, 0.03 g adsorbent dosage, 20 min shaking time at pH 7. Isotherm studies confirmed chemisorption, with a maximum adsorption capacity of 10.63 mg/g. Furthermore, CPAC demonstrated a removal efficiency of 31.01% to 49.29% for Cd, Cr, Cu, Mn and Zn in water samples collected from the Kelani river, Sri Lanka. These findings emphasize the viability of CPAC as a cost-effective, environmentally sustainable adsorbent for the remediation of heavy metal-laden water, thereby advancing sustainable waste management and environmental remediation.},

keywords = {Activated carbon, Adsorption, Adsorptive removal, Drinking water, wastewater},

pubstate = {published},

tppubtype = {article}

}

@article{Perera0000,

title = {Fabrication Of Activated Carbon/Chitosan Hybrid Material (ACCHM) For Adsorptive Removal of Pb (II)},

author = {PLRA Perera and WPRT Perera and CSK Rajapakse},

url = {https://rajithperera.com/full_text_1306-2/

https://science.lpnu.ua/jcct/all-volumes-and-issues/volume-17-number-4-2023/fabrication-activated-carbonchitosan-hybrid

https://science2016.lp.edu.ua/chcht/fabrication-activated-carbonchitosan-hybrid-material-adsorptive-removal-pb-ii

https://search.worldcat.org/title/10108193389?oclcNum=10108193389

https://www.semanticscholar.org/paper/Fabrication-of-Activated-Carbon-Chitosan-Hybrid-for-Perera-Perera/f0540eba95b7f0353a78a3ad8325228472c233d7?utm_source=direct_link

},

doi = {10.23939/chcht17.04.903},

year  = {2023},

date = {2023-12-19},

urldate = {2023-12-19},

journal = {Chemistry & Chemical Technology},

volume = {17},

issue = {4},

pages = {903-915},

abstract = {In this study, a novel, cost-effective and environmentally friendly activated carbon/chitosan hybrid material (ACCHM) was synthesized by incorporating surface properties of both the activated carbon derived from rice husk and chitosan extracted from Black Tiger” shrimp shells to generate a highly functionalized porous material with enhanced Pb (II) adsorption capacity for water purification.  },

keywords = {Activated carbon, Adsorptive removal, Biomass, Chitosan, Lead, Porous material},

pubstate = {published},

tppubtype = {article}

}