scholarly journals Adsorption Behaviors and Mechanisms of Cu2+, Zn2+ and Pb2+ by Magnetically Modified Lignite

2021 ◽  
Author(s):  
Junzhen Di ◽  
Zhen Ruan ◽  
Siyi Zhang
Keyword(s):  
Column Experiment ◽  
Raw Material ◽  
Order Model ◽  
Adsorption Effect ◽  
Intraparticle Diffusion Model ◽  
Mine Wastewater ◽  
Adsorption Processes ◽  
Stretching Vibration ◽  
Magnetic Modification ◽  
Infrared Spectrometer

Abstract In order to solve the problems of high content of Cu2+, Zn2+ and Pb2+ in acid mine wastewater (AMD), and limited adsorption capacity of lignite, the lignite was used as raw material to prepare magnetically modified lignite (MML), and adsorption performance of lignite and MML on Cu2+, Zn2+ and Pb2+ was investigated by static beaker experiment and dynamic continuous column experiment. At the same time, the adsorption mechanism was revealed by means of scanning electron microscopy (SEM), X-ray diffractometer (XRD) and Fourier transform infrared spectrometer (FTIR). The results showed that the adsorption processes of lignite and MML on heavy metal ions were more consistent with the Langmuir model, obeying the quasi first-order model and quasi second-order model, respectively. In addition, the intraparticle diffusion model indicated that the adsorption processes were jointly controlled by multiple adsorption stages. The dynamic continuous column experiments showed that the average removal rates of Cu2+, Zn2+ and Pb2+ were 78.00%, 76.97% and 78.65% for lignite and 82.83%, 81.57% and 83.50% for MML, respectively. Compared with lignite, the adsorption effect of MML was better. From SEM, XRD and FTIR tests, it can be seen that the magnetic modification process successfully loads Fe3O4 onto the surface of lignite, making the surface morphology rougher, and the adsorption process of MML on Cu2+, Zn2+ and Pb2+ is related to the O-H stretching vibration of carboxylic acid ions and Fe-O stretching vibration of Fe3O4 particles.

Synthesis and Thermal Property of Linear Chloromethylated Polystyrene

2010 ◽  
Vol 150-151 ◽  
pp. 1504-1507 ◽  
Author(s):  
Hong Chi Zhao ◽  
Juan Li Guo ◽  
Jiang Tao Li ◽  
Ling Ling Gao ◽  
Cong Cong Bian
Keyword(s):  
Gel Permeation Chromatography ◽  
Raw Material ◽  
Bending Vibration ◽  
Strong Absorption Band ◽  
Thermogravimetric Analyzer ◽  
Bond Stretching ◽  
Stretching Vibration ◽  
Infrared Spectrometer ◽  
Linear Poly ◽  
Aluminium Trichloride

Polystyrene (PS) was synthesized by emulsion polymerization. 1,4-bis(chloromethoxy)butane (BCMB) was synthesized using 1,4-butanediol, formaldehyde and phosphorus trichloride as raw material. The linear poly(p-chloromethyl styrene) (PS-Meyl-Cl) was prepared high effectively using BCMB and anhydrous aluminium trichloride as the chloromethylation reagent and catalyst, respectively. In this method, carcinogenic compound (chloromethyl ether etc.) was avoided. The resultant polymers were characterized by gel permeation chromatography (GPC), Fourier transform infrared spectrometer (FTIR) and thermogravimetric analyzer. The results show that the molecular weight (Mw) of PS is big. BCMB has been prepared because of the strong absorption band observed at 1130cm-1 (due to C-O-C bond stretching vibration) and two new bands at 640 and 1315cm-1 (due to the bending vibration of C-Cl bond and stretching vibration of C-H bond in -CH2Cl, respectively). Chloromethyl groups were introduced into benzene ring of PS because of the appearance of the absorption peaks at 676 and 1419cm-1 (due to the bending vibration of C-Cl bond and stretching vibration of C-H bond in -CH2Cl, respectively) in the FTIR spectra. The thermal stability of PS-Meyl-Cl was decreased with increasing chloromethyl group. Moreover, there are two decomposing stages. The reaction condition is gentle and the operation is safe, simple and economical.

scholarly journals Effective Magnetic MOFs Adsorbent for the Removal of Bisphenol A, Tetracycline, Congo Red and Methylene Blue Pollutions

Nanomaterials ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 1917
Author(s):  
Guangpu Zhang ◽  
Rong Wo ◽  
Zhe Sun ◽  
Gazi Hao ◽  
Guigao Liu ◽  
...  
Keyword(s):  
Methylene Blue ◽  
Electron Microscope ◽  
Bisphenol A ◽  
Congo Red ◽  
Reduction Process ◽  
Entropy Change ◽  
Potential Candidate ◽  
Order Kinetic ◽  
Adsorption Processes ◽  
Infrared Spectrometer

A magnetic metal−organic frameworks adsorbent (Fe3O4@MIL-53(Al)) was prepared by a typical solvothermal method for the removal of bisphenol A (BPA), tetracycline (TC), congo red (CR), and methylene blue (MB). The prepared Fe3O4@MIL-53(Al) composite adsorbent was well characterized by scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray diffraction (XRD), and fourier transform infrared spectrometer (FTIR). The influence of adsorbent quantity, adsorption time, pH and ionic strength on the adsorption of the mentioned pollutants were also studied by a UV/Vis spectrophotometer. The adsorption capacities were found to be 160.9 mg/g for BPA, 47.8 mg/g for TC, 234.4 mg/g for CR, 70.8 mg/g for MB, respectively, which is superior to the other reported adsorbents. The adsorption of BPA, TC, and CR were well-fitted by the Langmuir adsorption isotherm model, while MB followed the Freundlich model, while the adsorption kinetics data of all pollutants followed the pseudo-second-order kinetic models. The thermodynamic values, including the enthalpy change (ΔH°), the Gibbs free energy change (ΔG°), and entropy change (ΔS°), showed that the adsorption processes were spontaneous and exothermic entropy-reduction process for BPA, but spontaneous and endothermic entropy-increasing processes for the others. The Fe3O4@MIL-53(Al) was also found to be easily separated after external magnetic field, can be a potential candidate for future water treatment.

The Removal and Inhibitory Effect of CNTs on Model Viruses

2013 ◽  
Vol 743-744 ◽  
pp. 402-408 ◽  
Author(s):  
Shi Yuan Liu ◽  
Xiang Zheng ◽  
Ye Yang ◽  
Jia Liu ◽  
Jie Li
Keyword(s):  
Freundlich Isotherm ◽  
Inhibitory Effect ◽  
Multilayer Adsorption ◽  
Adsorption Effect ◽  
Ms2 Bacteriophage ◽  
Adsorption Processes ◽  
Pseudo Second Order ◽  
Static And Dynamic Tests ◽  
The Impact ◽  
Removal System

Nanomaterial is becoming an important adsorption or disinfection material for removing virus from drinking water. In this study, static and dynamic tests were used to examine adsorption and inhibition characteristics of carbon nanotubes (CNTs) on two model viruses -- f2 and MS2 bacteriophage. Controlling variate method was used to systematically investigate the adsorption kinetics and adsorption isotherms of CNTs on two model viruses; as well as to find the impact of different CNTs dosages on adsorption effect; and then to study the inhibitory effect of CNTs.The results showed that: (1) The adsorption process of f2 and MS2 bacteriophage on CNTs corresponded well with the pseudo-second-order kinetics equation. Time to reach a saturation equilibrium adsorption is about 30min. (2) Both the Langmuir and Freundlich isotherm adequately described two adsorption processes which indicated that the removal mechanism of virus was a mix of monolayer and multilayer adsorption. (3)The dosage of a single removal system should not be too high in practical application. (4) The inhibition of CNTs on model viruses exhibited.

scholarly journals Characterization and Evaluation of Zeolite A/Fe3O4 Nanocomposite as a Potential Adsorbent for Removal of Organic Molecules from Wastewater

2019 ◽  
Vol 2019 ◽  
pp. 1-13 ◽  
Author(s):  
Emmanuel Nyankson ◽  
Jonas Adjasoo ◽  
Johnson Kwame Efavi ◽  
Reuben Amedalor ◽  
Abu Yaya ◽  
...  
Keyword(s):  
Adsorption Process ◽  
Isotherm Models ◽  
Adsorption Efficiency ◽  
Ferrous Chloride ◽  
X Ray ◽  
Intraparticle Diffusion Model ◽  
Adsorption Processes ◽  
Langmuir Isotherm Model ◽  
Pseudo Second Order ◽  
Chloride Salts

In this work, zeolite (Z) and Z-Fe3O4 nanocomposite (Z-Fe3O4 NC) have been synthesized. The Fe3O4 nanoparticles were synthesized using the extract from maize leaves and ferric and ferrous chloride salts and encapsulated into the zeolite framework. The nanocomposite (Z-Fe3O4 NC) was characterized using X-ray diffractometer (XRD), Fourier-transform infrared (FT-IR) spectroscopy, energy-dispersive X-ray (EDX) spectroscopy, and scanning electron microscopy (SEM). The potential of Z-Fe3O4 NC as an adsorbent for removing methylene blue molecules (MB) from solution was examined using UV-Vis and kinetic and equilibrium isotherm models. The adsorption data fitted best with the pseudo-second-order model and Weber and Morris model, indicating that the adsorption process was chemisorption, while the Weber and Morris described the rate-controlling steps. The intraparticle diffusion model suggests that the adsorption processes were pore and surface diffusion controlled. The Langmuir isotherm model best describes the adsorption process indicating homogeneous monolayer coverage of MB molecules onto the surface of the Z-Fe3O4 NC. The maximum Langmuir adsorption capacity was 2.57 mg/g at 25°C. The maximum adsorption efficiency was 97.5%. After regeneration, the maximum adsorption efficiency achieved at a pH of 7 was 82.6%.

Synthesis and Thermal Property of Poly(Allylamine Hydrochloride)

2010 ◽  
Vol 150-151 ◽  
pp. 1480-1483 ◽  
Author(s):  
Hong Chi Zhao ◽  
Xiu Ting Wu ◽  
Wei Wei Tian ◽  
Shi Tong Ren
Keyword(s):  
Thermal Property ◽  
Chemical Shifts ◽  
Hydrogen Atoms ◽  
Nuclear Magnetic Resonance Spectrometer ◽  
Vibration Absorption ◽  
Thermogravimetric Analyzer ◽  
Stretching Vibration ◽  
Peak Areas ◽  
Infrared Spectrometer ◽  
Allylamine Hydrochloride

Poly(allylamine phosphate) (PAP) was synthesized by solution polymerization using allylamine phosphate (AP) as monomer, 2,2’-azo-bis-2-amidinopropane dihydrochloride (AAP•2HCl) as initiator, respectively. PAP reacted with concentrated hydrochloric acid and it converted into poly(allylamine hydrochloride) (PAH). The effects of varying the concentrations of initiator and monomer on the polymerization conversion were investigated in detail. The chemical structure and thermal property of the polymer were studied by Fourier transform infrared spectrometer (FTIR), nuclear magnetic resonance spectrometer (NMR), thermogravimetric analyzer (TGA), differential scanning calorimeter (DSC), X-ray diffractmeter (XRD), respectively. PAH was prepared because of the disappearance of the stretching vibration absorption peaks and deformation vibration absorption peak of C-H bonds in -C=CH2 at 3020cm-1, 3085cm-1 and 1310cm-1 in the FTIR spectra. The three peak areas and their chemical shifts were consistent with the three kinds of hydrogen atoms in polymer formula in 1H NMR spectrum, which proved that PAH was synthesized. PAH had three decomposing stages and it decomposed completely at 700oC. The glass transition temperature (Tg) of PAH increased with decreasing concentration of initiator. The conversion of monomer increased with the increasing concentrations of initiator and monomer.

scholarly journals Preparation of Synthetic Clays to Remove Phosphates and Ibuprofen in Water

Water ◽  
2021 ◽  
Vol 13 (17) ◽  
pp. 2394
Author(s):  
Rosa Devesa-Rey ◽  
Jesús del Val ◽  
Jorge Feijoo ◽  
José González-Coma ◽  
Gonzalo Castiñeira ◽  
...  
Keyword(s):  
Close Agreement ◽  
Adsorption Process ◽  
Intraparticle Diffusion ◽  
Phosphate Adsorption ◽  
Order Model ◽  
Intraparticle Diffusion Model ◽  
First Order ◽  
Pseudo Second Order ◽  
Double Hydroxide ◽  
Phosphate Desorption

The main objective of this study consists in the synthesis of a layered double hydroxide (LDH) clay doped with magnesium and aluminum in order to test the removal of phosphates and ibuprofen in water. Two different LDH composites are assessed: oven-dried (LDHD) and calcined (LDHC). Single adsorptions of phosphate and ibuprofen showed up to 70% and 58% removal in water, when LDHC was used. A poorer performance was observed for LDHD, which presented adsorption efficiencies of 52% and 35%, respectively. The simultaneous removal of phosphate and ibuprofen in water showed that LDHC allows a greater reduction in the concentration of both compounds than LDHD. Phosphate adsorption showed a close agreement between the experimental and theoretical capacities predicted by the pseudo-second-order model, whereas ibuprofen fitted to a first-order model. In addition, phosphate adsorption showed a good fit to an intraparticle diffusion model and to Bangham model suggesting that diffusion into pores controls the adsorption process. No other mechanisms may be involved in ibuprofen adsorption, apart from intraparticle diffusion. Finally, phosphate desorption could recover up to 59% of the initial concentration, showing the feasibility of the recuperation of this compound in the LDH.

scholarly journals Removal of Heavy Metals from Wastewater by Adsorption

2021 ◽  
Author(s):  
Athar Hussain ◽  
Sangeeta Madan ◽  
Richa Madan
Keyword(s):  
Heavy Metals ◽  
Metal Removal ◽  
Negative Impact ◽  
Low Cost ◽  
Agricultural Waste ◽  
Heavy Metal Removal ◽  
Raw Material ◽  
Removal Of Heavy Metals ◽  
Cost Effective Technique ◽  
Adsorption Processes

Adsorption processes are extensively used in wastewater treatment for heavy metal removal. The most widely used adsorbent is activated carbon giving the best of results but it’s high cost limits its use. It has a high cost of production and regeneration. As the world today faces a shortage of freshwater resources, it is inevitable to look for alternatives that lessen the burden on existing resources. Also, heavy metals are toxic even in trace concentrations, so an environmentally safe method of their removal necessitated the requirement of low cost adsorbents. Adsorption is a cost-effective technique and gained recognition due to its minimum waste disposal advantage. This chapter focuses on the process of adsorption and the types of adsorbent available today. It also encompasses the low-cost adsorbents ranging from agricultural waste to industrial waste explaining the adsorption reaction condition. The cost-effectiveness, technical applicability and easy availability of raw material with low negative impact on the system are the precursors in selecting the adsorbents. The novelty of the chapter lies in covering a wide range of adsorbents with their efficiency in removal of heavy metals from wastewater.

scholarly journals Characterization of algae residue biochar and its application in methyl orange wastewater treatment

2021 ◽  
Author(s):  
Hao Zhu ◽  
Haiming Zou
Keyword(s):  
Electron Microscopy ◽  
Methyl Orange ◽  
Raw Material ◽  
Batch Adsorption ◽  
Adsorption Method ◽  
Adsorption Effect ◽  
Transmission Electron ◽  
Langmuir Isotherm Model ◽  
Pseudo Second Order ◽  
Methyl Orange Dye

Abstract In this work, Spirulina residue was used as the raw material to prepare different biochars by changing the pyrolysis time. Moreover, the obtained products were characterized by scanning electron microscopy, transmission electron microscopy, Raman spectroscopy, Fourier transform infrared spectroscopy, and X-ray diffraction energy spectrum. This experiment used the batch adsorption method to study the adsorption effect of pH, dosage, and pyrolysis time on methyl orange. The adsorption of methyl orange onto Spirulina residue biochar fitted with the Langmuir isotherm model and pseudo-second-order kinetics. The results showed that the surface functional groups of Spirulina residue biochar obtained by dry pyrolysis were abundant, and it can effectively adsorb methyl orange dye in an aqueous solution. The sample prepared at 500 °C for 5 h had the best adsorption effect on methyl orange. The change of pyrolysis time will affect the physicochemical properties of biochar from Spirulina residue, thereby affecting its adsorption effect on methyl orange dye. The analysis showed that the chemical adsorption of Spirulina residue biochar on methyl orange might be the primary way of dye removal. The results can provide a reference for preparing biochar from algae residue and biochar application in the removal of dye wastewater.

scholarly journals Pembuatan Biodiesel dengan Cara Adsorpsi dan Transesterifikasi Dari Minyak Goreng Bekas

2016 ◽  
Vol 2 (1) ◽  
pp. 71-80
Author(s):  
Lisa Adhani ◽  
Isalmi Aziz ◽  
Siti Nurbayti ◽  
Christie Adi Octavia
Keyword(s):  
Particle Size ◽  
Adsorption Process ◽  
Acid Value ◽  
Raw Material ◽  
Optimal Conditions ◽  
Cooking Oil ◽  
Used Cooking Oil ◽  
Adsorption Processes ◽  
Oil Adsorption

Used cooking oil can be used as raw material for biodiesel, but the levels of free fatty acids (Free Fatty Acid, FFA) is quite high. It is necessary for pretreatment in the form of the adsorption process to reduce levels of FFA. This study aims to determine the optimal conditions of adsorption process and determine the quality of biodiesel produced from adsorption processes and transesterification. Natural zeolites are used as adsorbents activated beforehand using ammonium chloride, calcined and heated to obtain H-zeolite. Furthermore, the adsorption process optimization includes the time, the adsorbent concentration, temperature and particle size. The oil that is already in the adsorption catalyst is reacted with methanol and KOH to obtain biodiesel. The optimum adsorption conditions obtained at the time of 90 minutes, the concentration of H-zeolite 12%, temperature 90 ° C, and a particle size of 0.2 mm that can lower FFA levels from 3.2% to 1.1%. Biodiesel produced meets the quality requirements of SNI 04-7182-2006 with a water content of 0.02%, a density of 857.60 kg / m3, the acid value of 0.29 mg-KOH / g, iodine number 15.71, saponification 168 , 02 and cetane index of 75.62. Compounds contained in biodiesel are methyl 9-octadecanoic (49.45%), methyl heksadekanoat (20.79%), and methyl 9,12oktaekanoat 9.12 (18.87%). Keywords: Biodiesel, used cooking oil, adsorption, transesterification, H-zeolitDOI: http://dx.doi.org/10.15408/jkv.v2i1.3107

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