Kinetics of Mercury and Nickel Adsorption Using Chemically Pretreated Cocoa (Theobroma cacao) Husks

2019 ◽  
Vol 62 (2) ◽  
pp. 461-466 ◽  
Author(s):  
Candelaria Tejada-Tovar ◽  
Angel Villabona-Ortíz ◽  
Ángel Dario González-Delgado ◽  
María Jiménez-Villadiego

Abstract. Agroindustrial wastes have been widely used to prepare adsorbents for heavy metal removal because of their low cost, accessibility, and high efficiency. This work focuses on preparing a novel material from cocoa ( L.) husk residual biomass chemically modified with sodium hydroxide for used as a biosorbent for nickel and mercury uptake. The cocoa husk residual biomass was characterized by FT-IR analysis to test the diversification of functional groups. The effect of particle size on removal yield was evaluated through batch adsorption experiments. The experimental results were fitted to mathematical models to determine the adsorption kinetics and isotherms. Particle size significantly affected the adsorption process, and the highest removal yields (91.59% and 79.96%) were achieved using 0.36 mm and 0.5 mm particles for Hg (II) and Ni (II) ions, respectively. The adsorption kinetic model that best fit the experimental data corresponded to the Elovich model, with correlation coefficients (R2) above 0.89. The adsorption process of nickel and mercury onto cocoa husk biomass followed the Freundlich isotherm model. The results show that modification with sodium hydroxide improves the adsorption capacity of cocoa husk residual biomass, indicating that this novel material could be efficiently applied for nickel and mercury uptake. Keywords: Adsorption, Heavy metals, Removal yield.

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Waheed Ali Khoso ◽  
Noor Haleem ◽  
Muhammad Anwar Baig ◽  
Yousuf Jamal

AbstractThe heavy metals, such as Cr(VI), Pb(II) and Cd(II), in aqueous solutions are toxic even at trace levels and have caused adverse health impacts on human beings. Hence the removal of these heavy metals from the aqueous environment is important to protect biodiversity, hydrosphere ecosystems, and human beings. In this study, magnetic Nickel-Ferrite Nanoparticles (NFNs) were synthesized by co-precipitation method and characterized using X-Ray Diffraction (XRD), Energy Dispersive Spectroscopy (EDS) and Field Emission Scanning Electronic Microscopy (FE-SEM) techniques in order to confirm the crystalline structure, composition and morphology of the NFN’s, these were then used as adsorbent for the removal of Cr(VI), Pb(II) and Cd(II) from wastewater. The adsorption parameters under study were pH, dose and contact time. The values for optimum removal through batch-adsorption were investigated at different parameters (pH 3–7, dose: 10, 20, 30, 40 and 50 mg and contact time: 30, 60, 90, and 120 min). Removal efficiencies of Cr(VI), Pb(II) and Cd(II) were obtained 89%, 79% and 87% respectively under optimal conditions. It was found that the kinetics followed the pseudo second order model for the removal of heavy metals using Nickel ferrite nanoparticles.


YMER Digital ◽  
2021 ◽  
Vol 20 (11) ◽  
pp. 388-402
Author(s):  
T.N Balaji ◽  
◽  
S.M Ameenur Rahman ◽  
T Gomathi ◽  
S Pavithra ◽  
...  

Heavy metal removal from wastewater has become a major environmental concern around the world. The performance of a chitosan-oligosaccharide-based hybrid (chitosan oligosaccharide (COS)/Carboxymethyl cellulose (CMC)/Kaolin clay (KC) ternary blend material prepared in the presence of Glutaraldehyde (Glu) ternary blend material for the adsorptive removal of lead (Pb) from waterwaste was investigated in this study. The structure of COS with amine and hydroxyl groups helps to remove Pb ions. FTIR and X-Ray diffraction were used to characterize of COS/CMC/KC + Glu blend. The removal of ions was assessed using batch adsorption studies, which varied parameters such as the influence of beginning concentration, adsorbent dose, and contact time. The elimination of Pb ions by adsorption was pH-dependent, with a maximum at pH 5. The favorability of the reported experimental values was validated using several theoretical models such as Freundlich and Langmuir isotherms, pseudo-first-order and pseudo-second-order kinetics. The Langmuir isotherm and pseudosecond-order best fitted for the adsorption.


2016 ◽  
Vol 7 (4) ◽  
pp. 387-419 ◽  
Author(s):  
Renu ◽  
Madhu Agarwal ◽  
K. Singh

Heavy metals are discharged into water from various industries. They can be toxic or carcinogenic in nature and can cause severe problems for humans and aquatic ecosystems. Thus, the removal of heavy metals from wastewater is a serious problem. The adsorption process is widely used for the removal of heavy metals from wastewater because of its low cost, availability and eco-friendly nature. Both commercial adsorbents and bioadsorbents are used for the removal of heavy metals from wastewater, with high removal capacity. This review article aims to compile scattered information on the different adsorbents that are used for heavy metal removal and to provide information on the commercially available and natural bioadsorbents used for removal of chromium, cadmium and copper, in particular.


2019 ◽  
Vol 68 (7) ◽  
pp. 495-508
Author(s):  
Zhongmin Li ◽  
Wanwan Wu ◽  
Wenyan Jiang ◽  
Guangtao Wei ◽  
Yunshang Li ◽  
...  

Abstract The adsorption of Ni(II) by a thermo-sensitive adsorbent of methylcellulose/calcium alginate beads (CAMCBs) was studied using batch adsorption tests to determine the adsorption process and properties, the effects of adsorbent dosage, initial concentration, adsorption time and temperature. The adsorption process was further investigated using kinetics, isotherms and thermodynamic methods. The kinetics and isotherms studies showed the adsorption of Ni(II) on CAMCBs was fitted by the pseudo-second-order kinetic model and Langmuir isothermal adsorption model, respectively. The thermodynamic parameters indicated that the adsorption process was spontaneous and exothermic at lower temperature, and the entropy of the adsorption process was negative. In the study of regeneration, it was confirmed that under the temperature of 60 °C, the desorption agent of CaCl2 with concentration of 3 g·L−1 was more conducive to the desorption of Ni(II) from CAMCBs. Both adsorption capacity and mechanical strength of the used CAMCBs could be basically recovered to the level of fresh CAMCBs after desorption. The prepared CAMCBs had a good property of adsorption of Ni(II) and an excellent regeneration performance.


2018 ◽  
Vol 7 (3.18) ◽  
pp. 91 ◽  
Author(s):  
Khairul Anwar Mohamad Said ◽  
Nor Zakirah Ismail ◽  
Ramizah Liyana Jama'in ◽  
Nurul Ain Mohamed Alipah ◽  
Norsuzailina Mohamed Sutan ◽  
...  

The aim of this study was to investigate the application of membrane equipped activated carbon for heavy metal removal. An adsorption capacity of the activated carbon inside membrane matrix was performed against environmentally problematic ions specifically Pb2+, in aqueous solution. The adsorption process was examined by Temkin and Freundlich isotherm. From the SEM observation, membrane exhibit sponge-like structure with dense micro-void formation across the matrix. This phenomenon was usually observed with membrane mixed with polyethyleneimine. For the adsorption studies, it is shown that Freundlich isotherm show better fit based on R2 value of 0.9893 with Temkin isotherm fitted with R2 of 0.9009. Through the fitted model, the adsorption occur on the surface of activated carbon are possibly multilayer type adsorption based on theory by Freundlich isotherm and fall under non-ideal reversible adsorption.  


2019 ◽  
Vol 9 (8) ◽  
Author(s):  
Thair Sharif Khayyun ◽  
Ayad Hameed Mseer

Abstract The purpose of this study was to investigate the possibility of the limestone as an adsorbed media and low-cost adsorbent. Batch adsorption studies were conducted to examine the effects of the parameters such as initial metal ion concentration C0, particle size of limestone DL, adsorbent dosage and equilibrium concentration of heavy metal Ce on the removal of the heavy metal (Cu) from synthetic water solution by limestone. The removal efficiency is increased with the increase in the volume of limestone (influenced by the media specific area). It has been noted that the limestone with diameter of 3.75 is the most effective size for removal of copper from synthetic solution. The adsorption data were analyzed by the Langmuir and Freundlich isotherm model. The average values of the empirical constant and adsorption constant (saturation coefficient) for the Langmuir equation were a = 0.022 mg/g and b = 1.46 l/mg, respectively. The average values of the Freundlich adsorption constant and empirical coefficient were Kf = 0.010 mg/g and n = 1.58 l/mg, respectively. It was observed that the Freundlich isotherm model described the adsorption process with high coefficient of determination R2, better than the Langmuir isotherm model and for low initial concentration of heavy metal. Also, when the values of amount of heavy metal removal from solution are predicted by the Freundlich isotherm model, it showed best fits the batch study. It is clear from the results that heavy metal (Cu) removal with the limestone adsorbent appears to be technically feasible and with high efficiency.


2011 ◽  
Vol 695 ◽  
pp. 73-76 ◽  
Author(s):  
An Kai Luo ◽  
Xue Gang Luo ◽  
Xiao Yan Lin

The adsorption of Cd(II) ions from aqueous solution by sodium hydroxide-treated bamboo powder(STB) was studied in a batch adsorption system. Characteristics of STB were investigated by scanning electron microscopy (SEM) and electron dispersive spectroscopy (EDS). Factors influencing adsorption such as pH of the solution, adsorbent dosage, cadmium concentration and temperature have been studied. The adsorption process was relatively fast and equilibrium was achieved after 120 min, and the maximum adsorption of Cd(II) ions occurred at around pH 6.5. The equilibrium data were fitted using Langmuir, Temkin and Freundlich isotherm models to calculate isotherm constants. And the adsorption isotherm fitted well Langmuir isotherm, and the maximum adsorption capacity was 8.987 mg/g.


2019 ◽  
Vol 818 ◽  
pp. 77-81
Author(s):  
Ajeng Yulianti Dwi Lestari ◽  
Achmad Chafidz

Removing lead ion in aqueous solution using petai (Parkia speciosa) residue was done well. Petai residue is modified with sodium hydroxide and sulfuric acid before batch adsorption process occured. The results showed that the highest adsorption capacity was found in acid modification that was 2.62 mg/g.Temkin and Dubininmodels fit the adsorption isotherms of all adsorbents.


2013 ◽  
Vol 67 (11) ◽  
pp. 2406-2411 ◽  
Author(s):  
R. J. Petrell ◽  
Anastasia Gumulia

Little is known about the hydraulics of sloped compost beds having active free and non-flowing zones, and used for runoff erosion and volume control, and heavy metal removal. Water sorption tests on yard waste compost indicated that water transfer between the two zones would be slow (6 hr for a 0.04 m rise). The free flowing zone in ≈1 m long sloped (15°) beds increased in depth (0.01–0.08 m) with decreasing particle size and increasing flow. Particle size and flow (0.08–0.3 L/s/m) affected bed stability. Drainage volume increased with flow while drainage time remained fairly constant. Saturated flow occurred depending on the particle size above 0.02–0.165 L/s/m. Data indicate that sheet runoff from low intensity storms would most likely create unsaturated but stable bed conditions. Concentrated flows as from downspouts would likely create saturated conditions and have to be managed to prevent washout. A model based on porous media theory indicated that flow regime under saturated flow is turbulent. Results can be used to design compost beds for various runoff rates and to develop a heavy metal sorption model.


Sign in / Sign up

Export Citation Format

Share Document