Functionalization of Synthesized Nanoporous Silica and Its Application in Malachite Green Removal from Contaminated Water

Introduction: Nanoporous silica has received growing interest for its unique application potential in pollutant removal. Therefore, the development of a simple technique is required to synthesize and functionalize the nanoporous materials for industrial application. Materials and Methods: The synthesis of nanoporous silica was investigated by the template sol-gel method, and it functionalized as an adsorbent for adsorption of malachite green. The morphology and structure of the prepared and functionalized nanoporous silica were studied using X-ray diffraction, Fourier transform infrared spectroscopy (FT-IR), and nitrogen adsorption-desorption technique. Subsequently, the effective parameters such as solution pH, contact time, and initial concentration on the adsorption process were optimized by adsorption tests. Results: The results showed that high-order nanoporous silica had been produced with an average diameter of 20.12 nm and average pore volume of 1.04 cm3.g−1. It was found that the optimum parameters of pH, initial concentration and contact time for malachite green adsorption on nanoporous silica were 6.5, 10 mg.l-1, and 60 min, respectively. The experimental data confirmed the Freundlich model (R2 = 0.995) and the obtained kinetic data followed the pseudo-first-order equation. The maximum adsorption capacity calculated by Langmuir isotherm was found to be 116.3 mg.g-1. Conclusion: The high adsorption capacity showed that the acid-functionalized nanoporous silica adsorbent can be used as an adequate adsorbent to remove malachite green from aquatic environments. The large surface area can be suggested that the silica nanoporous will have potential application prospects as the adsorbent.

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Response Surface Methodology Approach for Optimization of Biosorption Process for Removal of Binary Metals by Immobilized Saccharomyces cerevisiae

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.661.51 ◽

2014 ◽

Vol 661 ◽

pp. 51-57

Author(s):

Mohd Zawawi Mohamad Zulhelmi ◽

Alrozi Rasyidah ◽

Senusi Faraziehan ◽

Mohamad Anuar Kamaruddin

Keyword(s):

Saccharomyces Cerevisiae ◽

Aqueous Solution ◽

Response Surface Methodology ◽

Response Surface ◽

Contact Time ◽

Optimization Procedure ◽

Effective Parameters ◽

Solution Ph ◽

Initial Concentration ◽

Biosorption Process

Biosorption process is considered as economical treatment to remove metal from the aqueous solution compared to other established methods. In this study, Saccharomyces cerevisiae was used as biosorbent and subject to immobilization process which consists of ethanol treatment for the removal of binary metals, lead (II) and nickel (II) from aqueous solution. Response surface methodology (RSM) was used to optimize effective parameters condition and the interaction of two or more parameters in order to obtain high removal of the binary metals. The parameters that have been studied were initial concentration of binary metals solution (10 - 60 mg/L), biosorbent dosage (0.2 - 1.0 g), pH (pH 2 - pH 6) and contact time (30 - 360 minutes) towards lead (II) and nickel (II) ions removal. Based on analysis of variance (ANOVA), biosorbent dosage, solution pH and contact time factor were found significant for both responses. Through optimization procedure, the optimum condition for lead (II) and nickel (II) ions removal were obtained at initial concentration of 10.0 mg/L, biosorbent dosage of 1.0 g, solution pH of pH 6, and contact time of 360.00 minutes, which resulted in 95.08 % and 21.09 % removal of lead (II) and nickel (II) ions respectively.

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MgO Functionalized Magnetic Activated Carbon Material for Efficient Removal of Malachite Green from Aqueous Solutions

NANO ◽

10.1142/s1793292021500545 ◽

2021 ◽

pp. 2150054

Author(s):

Zongli Ren ◽

Zhao Yang ◽

Zhongwei Zhao ◽

Xuan Yang

Keyword(s):

Activated Carbon ◽

Aqueous Solutions ◽

Malachite Green ◽

Contact Time ◽

Negative Impact ◽

Synthesis Method ◽

Maximum Adsorption Capacity ◽

Solution Ph ◽

Magnetic Activated Carbon ◽

The Cost

Malachite green (MG) pollution has a negative impact on human health. At present, the method of removing it is inconvenient to operate and the cost is high, which has aroused widespread concern. In this study, MgO functionalized magnetic activated carbon (MgO-mAC) prepared by the sol–gel method was used to remove MG in water. The physical and chemical properties of MgO-mAC were tested by SEM, TEM, FTIR, XRD, BET and VSM. The effects of adsorbent dosage, solution pH, contact time, initial MG concentration and temperature on adsorption were studied by batch experiments. The adsorption kinetics data is well described by a pseudo-second-order model. The equilibrium data fits the Langmuir isotherm well. When the pH is 8 and the contact time is 360[Formula: see text]min, the maximum adsorption capacity of MG is 3809[Formula: see text]mg[Formula: see text]g[Formula: see text]. In thermodynamic studies, [Formula: see text], [Formula: see text], [Formula: see text], MG adsorption is an endothermic and spontaneous adsorption process. The current synthesis method is simple in operation and cheap in raw materials, which can greatly reduce the cost of synthesis. Hence, the MgO-mAC material will be an effective adsorbent for removing MG from aqueous solutions.

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Determination of Adsorption Capacity of Agricultural-Based Carbon for Ni (II) Adsorption from Aqueous Solution

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.567.20 ◽

2014 ◽

Vol 567 ◽

pp. 20-25 ◽

Cited By ~ 3

Author(s):

Taimur Khan ◽

Mohamed Hasnain Isa ◽

Malay Chaudhuri ◽

Raza Ul Mustafa Muhammad ◽

Mohamed Osman Saeed

Keyword(s):

Aqueous Solution ◽

Adsorption Capacity ◽

Rice Husk ◽

Contact Time ◽

Low Cost ◽

Equilibrium Adsorption ◽

Batch Adsorption ◽

Average Pore ◽

Initial Concentration ◽

Rice Husk Carbon

The aim of the study was to prepare potentially cheaper carbon for the adsorptive removal of Nickle [Ni (II)] from aqueous solution. The adsorption capacity of the prepared carbon to remove Ni (II) from aqueous solution was determined and adsorption mechanism was investigated. Rice husk carbon was prepared by incineration in a muffle furnace. The incinerated rice husk carbon (IRHC) was characterised in terms of surface area, micropore area, micropore volume, average pore diameter and surface morphology. Adsorption of Ni (II) by IRHC was examined. The influence of operating parameters, namely, pH, initial concentration and contact time on adsorption of Ni (II) by IRHC was evaluated. Batch adsorption tests showed that extent of Ni (II) adsorption depended on initial concentration, contact time and pH. Equilibrium adsorption was achieved in 120 min, while maximum Ni (II) adsorption occurred at pH 4. Langmuir and Freundlich isotherms were studied and the equilibrium adsorption data was found to fit well with the Langmuir isotherm model. Langmuir constants Q° and b were 14.45 and 0.10, and Freundlich constants Kf and 1/n were 4.0 and 0.26, respectively. Adsorption of Ni (II) by IRHC followed pseudo-second-order kinetics. Being a low-cost carbon, IRHC has potential to be used for the adsorption of Ni (II) from aqueous solution and wastewater in developing countries.

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Removal of Fluoride on Chitosan Coated Alumina (CAL) from Aqueous Solution

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.518-523.797 ◽

2012 ◽

Vol 518-523 ◽

pp. 797-800 ◽

Cited By ~ 2

Author(s):

Xuan Lin Tang ◽

Huan Zhen Zhang ◽

Shuang Zhao ◽

Shu Fen Gong

Keyword(s):

Aqueous Solution ◽

Adsorption Capacity ◽

Contact Time ◽

Adsorption Rate ◽

Fluoride Removal ◽

Batch Experiments ◽

Solution Ph ◽

Initial Concentration ◽

Adsorbent Dosage ◽

Naoh Solution

CAL beads were made by dropping wise mixture of chitosan and alumina into NaOH solution. Effects of contact time, adsorbent dosage, initial concentration and pH on fluoride removal were carried out by batch experiments. Results show that adsorption rate was relatively rapid in the first 6 h, thereafter distinctly decreased until adsorption reached the equilibrium within 48 h, at this time, adsorption capacity was up to 0.67 mg/g, which was much higher than raw chitosan (0.052 mg/g). Fluoride removal increased significantly with an increase of adsorbent dosage, however, it rose slowly when the adsorbent dosage was above 16 g/L. Adsorption capacity reduced from 0.75 mg/g to 0.64mg/g when solution pH rose from 4 to 7, nevertheless, adsorption was relatively independent on solution pH between 7 and 10.

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Adsorption of Two Heavy Metal Ions on Dry Garlic Stem

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.396-398.2443 ◽

2011 ◽

Vol 396-398 ◽

pp. 2443-2446

Author(s):

Neng Zhou ◽

Zhen Zhou ◽

Yuan Qin ◽

Chu Jie Zeng ◽

Zu Qiang Huang

Keyword(s):

Adsorption Capacity ◽

Contact Time ◽

Heavy Metal Ions ◽

Adsorption Rate ◽

Batch Adsorption ◽

Maximum Adsorption Capacity ◽

Experimental Conditions ◽

Adsorption Time ◽

Initial Concentration ◽

Adsorption Temperature

This study reported the feasibility of adsorption of heavy metals using dry garlic stem, an environmentally-friendly and natural adsorbent．Using batch adsorption technique, the efficiency of the adsorbent was studied under different experimental conditions by varying parameters such as pH, initial concentration and contact time. The results show that at pH 2.03, adsorption temperature 35°C, the adsorption time 90 min and the amount of garlic stem 1.0 g, Pb2+ have the maximum adsorption capacity. The maximum adsorption capacity of the Pb2+ on garlic stem is 28.42 mg/g and the adsorption rate is 94.74%. At pH 4.05, the adsorption time 120 min and the amount of garlic stem 1.0, Cu2+ have the maximum adsorption at the same temperature. The maximum adsorption of the Cu2+ is 20.90 mg/g and the adsorption rate is 69.75%. The dry garlic stem was found to be efficient in removing lead and copper from aqueous solution as compared to other adsorbents already used for the removal of these ions.

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emoval of malachite green dye from aqueous solutions by diasporic Greek raw bauxite

Bulletin of the Geological Society of Greece ◽

10.12681/bgsg.11132 ◽

2017 ◽

Vol 47 (2) ◽

pp. 927 ◽

Cited By ~ 1

Author(s):

I.K. Georgiadis ◽

A. Papadopoulos ◽

A. Filippidis ◽

A. Godelitsas ◽

A. Tsirambides ◽

...

Keyword(s):

Aqueous Solutions ◽

Adsorption Capacity ◽

Malachite Green ◽

Sugar Cane ◽

Contact Time ◽

Initial Concentration ◽

Root Carbon ◽

Malachite Green Dye ◽

Batch Type ◽

Removal Capacity

Raw bauxite from Klisoura mine (Prefecture of Fokida, Greece) containing 72 wt.% diaspore, 16 wt.% hematite, 6 wt.% quartz, 4 wt.% anatase and 2 wt.% calcite, has been used for the removal of malachite green dye from aqueous solutions. The batch type experiments were conducted with 10 ml of solution, at pH = pHZPC = 6.7 and contact time 1 h. The initial concentration of malachite green dye was 10 mg/l, the bauxite quantity was 0.02 g, 0.04 g, 0.06 g, 0.1 g and 0.2 g. The highest adsorption capacity achieved was 4.5 mg/g (90% removal) using 0.02 g bauxite. The removal capacity of raw bauxite is comparable to other non-conventional adsorbents, such as neem sawdust, sugar cane dust and cane root carbon.

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Removal of Arsenic from Wastewater by Using Pretreating Orange Peel

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.773.889 ◽

2013 ◽

Vol 773 ◽

pp. 889-892 ◽

Cited By ~ 1

Author(s):

Yuan Peng ◽

Hong Yan Xiao ◽

Xian Zhong Cheng ◽

Hong Mei Chen

Keyword(s):

Aqueous Solutions ◽

Adsorption Capacity ◽

Contact Time ◽

Low Cost ◽

Orange Peel ◽

Local Fields ◽

Maximum Adsorption Capacity ◽

Solution Ph ◽

Adsorption Removal ◽

Removal Of Arsenic

The use of low-cost and eco-friendly adsorbents has been investigated as an ideal alternative to the currentexpensive methods of removing arsenic from wastewater. Orange peel was collected from the local fields of orangetrees and converted into a low-cost adsorbent. The effects of solution pH, contact time, and concentration of orange peel have beenstudied. The maximum adsorption capacity calculated from the Langmuirisotherm model was 43.69 mg g-1,Based on the adsorption capacity, the pretreating orange peel was shown to be promising materials for adsorption removal ofarsenics from aqueous solutions.

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Adsorptive and Coagulative Removal of Trace Metals from Water Using Surface Modified Sawdust-Based Cellulose Nanocrystals

J ◽

10.3390/j4020016 ◽

2021 ◽

Vol 4 (2) ◽

pp. 193-205

Author(s):

Opeyemi A. Oyewo ◽

Sam Ramaila ◽

Lydia Mavuru ◽

Taile Leswifi ◽

Maurice S. Onyango

Keyword(s):

Trace Metals ◽

Adsorption Capacity ◽

Cellulose Nanocrystals ◽

Inductively Coupled Plasma ◽

Electrostatic Interactions ◽

Natural Waters ◽

Maximum Adsorption Capacity ◽

Solution Ph ◽

Major Drawback ◽

Surface Modified

The presence of toxic metals in surface and natural waters, even at trace levels, poses a great danger to humans and the ecosystem. Although the combination of adsorption and coagulation techniques has the potential to eradicate this problem, the use of inappropriate media remains a major drawback. This study reports on the application of NaNO2/NaHCO3 modified sawdust-based cellulose nanocrystals (MCNC) as both coagulant and adsorbent for the removal of Cu, Fe and Pb from aqueous solution. The surface modified coagulants, prepared by electrostatic interactions, were characterized using Fourier transform infrared, X-ray diffraction (XRD), and scanning electron microscopy/energy-dispersive spectrometry (SEM/EDS). The amount of coagulated/adsorbed trace metals was then analysed using inductively coupled plasma atomic emission spectroscopy (ICP-AES). SEM analysis revealed the patchy and distributed floccules on Fe-flocs, which was an indication of multiple mechanisms responsible for Fe removal onto MCNC. A shift in the peak position attributed to C2H192N64O16 from 2θ = 30 to 24.5° occurred in the XRD pattern of both Pb- and Cu-flocs. Different process variables, including initial metal ions concentration (10–200 mg/L), solution pH (2–10), and temperature (25–45 °C) were studied in order to investigate how they affect the reaction process. Both Cu and Pb adsorption followed the Langmuir isotherm with a maximum adsorption capacity of 111.1 and 2.82 mg/g, respectively, whereas the adsorption of Fe was suggestive of a multilayer adsorption process; however, Fe Langmuir maximum adsorption capacity was found to be 81.96 mg/g. The sequence of trace metals removal followed the order: Cu > Fe > Pb. The utilization of this product in different water matrices is an effective way to establish their robustness.

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Full Factorial Design for Gold Recovery from Industrial Solutions

Toxics ◽

10.3390/toxics9050111 ◽

2021 ◽

Vol 9 (5) ◽

pp. 111

Author(s):

Maria Mihăilescu ◽

Adina Negrea ◽

Mihaela Ciopec ◽

Petru Negrea ◽

Narcis Duțeanu ◽

...

Keyword(s):

Factorial Design ◽

Adsorption Capacity ◽

Contact Time ◽

Adsorption Process ◽

Design Method ◽

Precious Metals ◽

Gold Recovery ◽

Maximum Adsorption Capacity ◽

Gold Concentration ◽

Commercial Resin

Gold is one of the precious metals with multiple uses, whose deposits are much smaller than the global production needs. Therefore, extracting maximum gold quantities from industrial diluted solutions is a must. Am-L-GA is a new material, obtained by an Amberlite XAD7-type commercial resin, functionalized through saturation with L-glutamic acid, whose adsorption capacity has been proved to be higher than those of other materials utilized for gold adsorption. In this context, this article presents the results of a factorial design experiment for optimizing the gold recovery from residual solutions resulting from the electronics industry using Am-L-GA. Firstly, the material was characterized using atomic force microscopy (AFM), to emphasize the material’s characteristics, essential for the adsorption quality. Then, the study showed that among the parameters taken into account in the analysis (pH, temperature, initial gold concentration, and contact time), the initial gold concentration in the solution plays a determinant role in the removal process and the contact time has a slightly positive effect, whereas the pH and temperature do not influence the adsorption capacity. The maximum adsorption capacity of 29.27 mg/L was obtained by optimizing the adsorption process, with the control factors having the following values: contact time ~106 min, initial Au(III) concentration of ~164 mg/L, pH = 4, and temperature of 25 °C. It is highlighted that the factorial design method is an excellent instrument to determine the effects of different factors influencing the adsorption process. The method can be applied for any adsorption process if it is necessary to reduce the number of experiments, to diminish the resources or time consumption, or for expanding the investigation domain above the experimental limits.

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Removal of Chromium(III) and Cadmium(II) Heavy Metal Ions from Aqueous Solutions Using Treated Date Seeds: An Eco-Friendly Method

Molecules ◽

10.3390/molecules26123718 ◽

2021 ◽

Vol 26 (12) ◽

pp. 3718

Author(s):

Mohammad Azam ◽

Saikh Mohammad Wabaidur ◽

Mohammad Rizwan Khan ◽

Saud I. Al-Resayes ◽

Mohammad Shahidul Islam

Keyword(s):

Metal Ions ◽

Adsorption Capacity ◽

Low Cost ◽

Maximum Adsorption Capacity ◽

Solution Ph ◽

Surface Analysis Techniques ◽

Adsorption Processes ◽

Ft Ir ◽

Metal Elution ◽

Date Pits

The aim of the research was to prepare low-cost adsorbents, including raw date pits and chemically treated date pits, and to apply these materials to investigate the adsorption behavior of Cr(III) and Cd(II) ions from wastewater. The prepared materials were characterized using SEM, FT-IR and BET surface analysis techniques for investigating the surface morphology, particle size, pore size and surface functionalities of the materials. A series of adsorption processes was conducted in a batch system and optimized by investigating various parameters such as solution pH, contact time, initial metal concentrations and adsorbent dosage. The optimum pH for achieving maximum adsorption capacity was found to be approximately 7.8. The determination of metal ions was conducted using atomic adsorption spectrometry. The experimental results were fitted using isotherm Langmuir and Freundlich equations, and maximum monolayer adsorption capacities for Cr(III) and Cd(II) at 323 K were 1428.5 and 1302.0 mg/g (treated majdool date pits adsorbent) and 1228.5 and 1182.0 mg/g (treated sagai date pits adsorbent), respectively. It was found that the adsorption capacity of H2O2-treated date pits was higher than that of untreated DP. Recovery studies showed maximal metal elution with 0.1 M HCl for all the adsorbents. An 83.3–88.2% and 81.8–86.8% drop in Cr(III) and Cd(II) adsorption, respectively, were found after the five regeneration cycles. The results showed that the Langmuir model gave slightly better results than the Freundlich model for the untreated and treated date pits. Hence, the results demonstrated that the prepared materials could be a low-cost and eco-friendly choice for the remediation of Cr(III) and Cd(II) contaminants from an aqueous solution.

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