Adsorption of Dopamine-hydrochloride (DPH) from Aqueous Solution

1970 ◽  
Vol 3 (1) ◽  
Author(s):  
ME Quayum ◽  
RJ Mannan ◽  
Syed Golam Rahman
Keyword(s):  
Aqueous Solution ◽  
Adsorption Isotherm ◽  
Linear Trend ◽  
Solid Surfaces ◽  
Multilayer Adsorption ◽  
Initial Concentration ◽  
Ph Values ◽  
Systematic Pattern ◽  
Dopamine Hydrochloride ◽  
Adsorption Phenomena

Adsorption of dopamine hydrochloride 3-hydroxy tyraminium chloride on solid surfaces like silica gel, alumina, kaolin and attapulgite from aqueous solution under different pH values were studied. It was observed that the extent of adsorption of dopamine hydrochloride (DPH) with various pH values did not show any systematic pattern for all the four solids. In most cases it was found that pH has little influence on the extent of adsorption even though adsorption increased with increasing initial concentration of the adsorbate solution. The Langmuir plots in most cases showed non-linear trend indicating multilayer adsorption. Adsorption of DPH on all four solids was consistent with the Frendlich adsorption isotherm and thus it is evident that the multilayer adsorption takes place from solutions. The adsorption phenomena were kinetically found to be ideal and it is confirmed from the experimental results that DPH does not interact with any of the four solids. The adsorption phenomena were investigated with respect to change in concentration, temperatures and duration of the process. Key words: Adsorption, DPH, Monolayer and multilayer, pH and concentration varieties. Dhaka Univ. J. Pharm. Sci. Vol.3(1-2) 2004 The full text is of this article is available at the Dhaka Univ. J. Pharm. Sci. website

Studies on the Treatment of Wastewaters Containing Cr6+ with Iron Oxide-Silica Composite Materials Prepared by Different Methods

2014 ◽  
Vol 353 ◽  
pp. 33-38
Author(s):  
Rafique Ullah ◽  
Biplob Kumer Deb ◽  
Mohammad Yousuf Ali Mollah
Keyword(s):  
Aqueous Solution ◽  
Iron Oxide ◽  
Adsorption Isotherm ◽  
Aqueous Solutions ◽  
Order Kinetic ◽  
Efficient Technology ◽  
Experimental Conditions ◽  
Initial Concentration ◽  
Oxide Composite ◽  
Chromium Vi

Chromium (VI) is known to be carcinogenic to humans and thus it is important to ensure the removal of Chromium (VI) from aqueous solutions and industrial effluents. The present study introduces a good alternative method for Cr (VI) removal from aqueous solutions at ambient temperature by adsorption, allowing the development of newer, lower operational cost, and more efficient technology than other processes already in use. Adsorption was found to be dependent on pH and initial concentration of Cr (VI) solution. Results of adsorption studies suggest that pristine iron oxide and silicon (IV) oxide removes 72.10% and 24.73%, respectively. The iron oxide – silicon (IV) oxide composite, prepared in this work, removes 93.88% Cr (VI) in 20 minutes from aqueous solution at an initial concentration of 50 mgL-1at pH 4.8 ± 0.2. The effect of concentration, contact time, adsorbent dose and solution pH on the adsorption of Cr (VI) were studied in detail in batch experiments. Studies of the sorption kinetics shows that equilibrium adsorption was attained in 20 minutes depending on other experimental conditions. The kinetic data justified Lagergren’s first-order kinetic equation. Adsorption isotherm study showed that the results fulfilled the Langmuir Model of adsorption isotherm. The maximum adsorption (98.28%) was recorded at pH 3 in 90 minutes for the initial Cr (VI) concentration of 50 mg L-1. Therefore, it can be concluded that iron oxide – silicon (IV) oxide composite is a potential adsorbent for adsorption of Cr (VI) from aqueous solution.

Decomposition of 2-chlorophenol in aqueous solution by ultrasound/H2O2 process

1996 ◽  
Vol 33 (6) ◽  
pp. 75-81 ◽  
Author(s):  
Lin Jih-Gaw ◽  
Chang Cheng-Nan ◽  
Wu Jer-Ren
Keyword(s):  
Aqueous Solution ◽  
Organic Contaminants ◽  
Power Input ◽  
Order Reaction ◽  
Pseudo First Order Reaction ◽  
Initial Concentration ◽  
First Order ◽  
Ph Values ◽  
Cp Decomposition ◽  
Pseudo First Order

Several authors have indicated that ultrasound is effective in oxidizing organic contaminants in water and in wastewater either as the sole means of treatment or in combination with ozonation and UV irradiation. In this work we decomposed 2-chlorophenol (2-cp) in aqueous solution with ultrasound and H2O2. The experiment was conducted with a sonicator (Microson XL-2020) operated at 20 kHz. The double amplitude at the tip of the standard horn (12.7 mm) was adjusted to 0, 72 and 120 μm, corresponding to power input 0, 125 and 160 W. The initial concentration of aqueous 2-cp solution was 100 mg/l, treated in the system with 0, 100, 200 and 500 mg/l H2O2 individually. The volume of solution was 1 l in a mixing flask, and was circulated to the sonication cell at the rate 500 mL/min. Oxygen was continuously purged into the flask. The temperature of solution was kept constant at 25°C and pH was controlled at 3, 5, 7, 9 and 11. The results showed the decomposition of 2-cp was effective at increased amplitude of ultrasound and concentration of H2O2, and smaller pH. At reaction duration 360 min, 2-cp decomposition with 500 mg/l H2O2 was found with 57% improvement over the control, i.e. without H2O2 addition. The pH, controlled below the pKa of 2-cp (8.49 at 25°C), had significantly better decomposition of 2-cp than at greater values. The decomposition rate of 100 mg/l 2-cp was 99% at 120 μm double amplitude with H2O2 (200 mg/L) and pH 3, after 360 min of reaction. The removal of total organic carbon was found to be only 63%. From analysis of the experimental results, the data on 2-cp decomposition appeared to follow pseudo-first-order reaction kinetics. The squared correlation coefficient, R2, of the model was greater than 0.9 for various pH values.

Adsorption of Cr (VI) from Aqueous Solution by Purified Attapulgite

2014 ◽  
Vol 1051 ◽  
pp. 583-587
Author(s):  
Ling Tao ◽  
Xiao Wei Song ◽  
Jian Li Yuan ◽  
Jun Ren ◽  
Yan Zhuo Zhang
Keyword(s):  
Aqueous Solution ◽  
Adsorption Isotherm ◽  
Aqueous Solutions ◽  
Contact Time ◽  
Order Equation ◽  
Langmuir Model ◽  
Initial Concentration ◽  
Pseudo Second Order ◽  
Equilibrium Adsorption Isotherm ◽  
Good Agreement

Adsorption of Cr6+ onto purified attapulgite was investigated with respect to temperature, initial concentration and contact time. The kinetics data related to the adsorption of chromium from aqueous solutions are in good agreement with the pseudo-second order equation in ranges of initial concentration of 20~200 mg/L, and temperature of 298~328K. The thermodynamic experiment results show that the equilibrium adsorption isotherm was closely fitted with the Langmuir model.

scholarly journals Methylene blue degradation assessment by advance oxidation methods

2019 ◽  
Vol 17 (3) ◽  
Author(s):  
B. Jaramillo Sierra ◽  
A. Mercado Cabrera ◽  
A. N. Hernández Arias ◽  
R. Peña Eguiluz ◽  
R. López Callejas ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Methylene Blue ◽  
Experimental Investigation ◽  
Advanced Oxidation Processes ◽  
Treatment Time ◽  
Methylene Blue Degradation ◽  
Initial Concentration ◽  
Oxidation Processes ◽  
Contaminant Degradation ◽  
Ph Values

Experimental investigation about methylene blue degradation in aqueous solution applying several Advanced Oxidation Processes such as O3, O3/H2O2, O3/UV and O3/UV and O3/UV/H2O2 was accomplished. Methylene blue treatment consisted in evaluating the degradation of an initial concentration of 22 ppm in 500 ml of aqueous solution. The contaminant degradation of an initial concentration of 22 ppm in 500 ml of aqueous solution. The contaminant degradation efficiencies were analyzed considering parameters such as: treatment time, three different pH values for the solution and O3 and H2O2 as oxidizing reagents. The discoloration of the samples was examined throughout the experimental each 10 minutes. Using O3/UV/H2O2 (10 ppm) with an initial 7 pH and a treatment time of 60 minutes the highest degradation efficiency of 98% was achieved.

Comparative Bio-sorption of Cadmium and Nickel Ions from Aqueous Solution onto Fibers of Date Palm using Fluidized Bed Column

2019 ◽  
Vol 70 (5) ◽  
pp. 1507-1512
Author(s):  
Baker M. Abod ◽  
Ramy Mohamed Jebir Al-Alawy ◽  
Firas Hashim Kamar ◽  
Gheorghe Nechifor
Keyword(s):  
Aqueous Solution ◽  
Heavy Metal ◽  
Metal Ions ◽  
Fluidized Bed ◽  
Removal Efficiency ◽  
Heavy Metal Ions ◽  
Date Palm ◽  
Operating Conditions ◽  
Initial Concentration ◽  
Bed Height

The aim of this study is to use the dry fibers of date palm as low-cost biosorbent for the removal of Cd(II), and Ni(II) ions from aqueous solution by fluidized bed column. The effects of many operating conditions such as superficial velocity, static bed height, and initial concentration on the removal efficiency of metal ions were investigated. FTIR analyses clarified that hydroxyl, amine and carboxyl groups could be very effective for bio-sorption of these heavy metal ions. SEM images showed that dry fibers of date palm have a high porosity and that metal ions can be trapped and sorbed into pores. The results show that a bed height of 6 cm, velocity of 1.1Umf and initial concentration for each heavy metal ions of 50 mg/L are most feasible and give high removal efficiency. The fluidized bed reactor was modeled using ideal plug flow and this model was solved numerically by utilizing the MATLAB software for fitting the measured breakthrough results. The breakthrough curves for metal ions gave the order of bio-sorption capacity as follow: Cd(II)]Ni(II).

Use of Nanopillars-TiO2 Thin Films in the Photocatalytic Degradation of Bromophenol Blue from Aqueous Solution

2018 ◽  
Vol 6 (1) ◽  
pp. 22-30
Author(s):  
C. Lalhriatpuia ◽  
◽  
Thanhming liana ◽  
K. Vanlaldinpuia
Keyword(s):  
Thin Films ◽  
Aqueous Solution ◽  
Photocatalytic Activity ◽  
Photocatalytic Degradation ◽  
Batch Reactor ◽  
Bromophenol Blue ◽  
Tio2 Thin Films ◽  
Initial Concentration ◽  
Bet Specific Surface Area ◽  
Interfering Ions

The photocatalytic activity of Nanopillars-TiO2 thin films was assessed in the degradation of Bromophenol blue (BPB) dye from aqueous solution under batch reactor operations. The thin films were characterized by the XRD, SEM and AFM analytical methods. BET specific surface area and pore sizes were also obtained. The XRD data showed anatase phase of TiO2 particles with average particle size of 25.4 and 21.9 nm, for S1 and S2 catalysts respectively. The SEM and AFM images indicated the catalyst composed with Nanosized pillars of TiO2, evenly distributed on the surface of the substrate. The average height of the pillars was found to be 180 and 40 nm respectively for the S1 and S2 catalyst. The BET specific surface area and pore sizes of S1 and S2 catalyst were found to be 5.217 and 1.420 m2/g and 7.77 and 4.16 nm respectively. The photocatalytic degradation of BPB using the UV light was studied at wide range of physico-chemical parametric studies to determine the mechanism of degradation as well as the practical applicability of the technique. The batch reactor operations were conducted at varied pH (pH 4.0 to 10.0), BPB initial concentration (1.0 to 20.0 mg/L) and presence of several interfering ions, i.e., cadmium nitrate, copper sulfate, zinc chloride, sodium chloride, sodium nitrate, sodium nitrite, glycine, oxalic acid and EDTA in the photocatalytic degradation of BPB. The maximum percent removal of BPB was observed at pH 6.0 and a low initial concentration of the pollutant highly favours the photocatalytic degradation using thin films. The presence of several interfering ions suppressed the photocatalytic activity of thin films to some extent. The time dependence photocatalytic degradation of BPB was demonstrated with the pseudo-first-order rate kinetics. Study was further extended with total organic carbon measurement using the TOC (Total Organic Carbon) analysis. This demonstrated an apparent mineralization of BPB from aqueous solutions.

scholarly journals Double-Cross-Linked Networks Based on Methacryloyl Mucin

Polymers ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 1706
Author(s):  
Elena Olăreț ◽  
Brîndușa Bălănucă ◽  
Andra Mihaela Onaș ◽  
Jana Ghițman ◽  
Horia Iovu ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Aqueous Solution ◽  
Chemical Modification ◽  
Structural Modification ◽  
Aqueous Media ◽  
Cross Linking ◽  
Ph Values ◽  
Acid Aqueous Solution ◽  
Reaction Media ◽  
Double Cross

Mucin is a glycoprotein with proven potential in the biomaterials field, but its use is still underexploited for such applications. The present work aims to produce a synthesis of methacryloyl mucin single-network (SN) hydrogels and their double-cross-linked-network (DCN) counterparts. Following the synthesis of the mucin methacryloyl derivative, various SN hydrogels are prepared through the photopolymerization of methacrylate bonds, using reaction media with different pH values. The SN hydrogels are converted into DCN systems via supplementary cross-linking in tannic acid aqueous solution. The chemical modification of mucin is described, and the obtained product is characterized; the structural modification of mucin is assessed through FTIR spectroscopy, and the circular dichroism and the isoelectric point of methacryloyl mucin is evaluated. The affinity for aqueous media of both SN and DCN hydrogels is estimated, and the mechanical properties of the systems are assessed, both at macroscale through uniaxial compression and rheology tests and also at microscale through nanoindentation tests.

Determination and correlation of solubility of thiamine nitrate in water+ethanol mixtures and aqueous solution with different pH values from 278.15K to 303.15K

2015 ◽  
Vol 400 ◽  
pp. 53-61 ◽  
Author(s):  
Haisheng Wang ◽  
Yujia Qin ◽  
Dandan Han ◽  
Xiaona Li ◽  
Yan Wang ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Ph Values

scholarly journals Preliminary Study on the Use of Ozonation for the Degradation of Dithiocarbamate Residues in the Fruit Drying Process: Mancozeb Residue in Blackcurrant is the Example Used

2013 ◽  
Vol 53 (1) ◽  
pp. 48-52 ◽  
Author(s):  
Piotr Antos ◽  
Anna Kurdziel ◽  
Stanisław Sadło ◽  
Maciej Balawejder
Keyword(s):  
Aqueous Solution ◽  
Ozone Concentration ◽  
Gaseous Phase ◽  
Plant Material ◽  
Water Solution ◽  
Ozone Treatment ◽  
Drying Process ◽  
Initial Concentration ◽  
Preliminary Study ◽  
Treatment Procedures

Abstract In order to reduce the level of dithiocarbamate fungicide mancozeb residues in blackcurrants, two different ozone treatment procedures were evaluated. The first one entailed washing the plant material with an aqueous solution of ozone. This ozone enriched water solution allowed for a 59% reduction of mancozeb residues, compared with the initial concentration. The latter method was based on the utilization of ozone in a gaseous phase combined with a drying process. In that procedure, samples of blackcurrant fruit were exposed to a 19 ppm ozone concentration, and then the blackcurrants were dried. The utilization of ozone in a gaseous phase permitted a 38% reduction of mancozeb residues, in comparison with the initial concentration. As a result of the combination of both processes; ozonation and drying, a 58% reduction of mancozeb residues was achieved.

Effects of Surface Properties and Solvent PH Values on the Adsorption/Desorption Abilities of Mesoporous SBA-15 to Methylene Blue Molecules

2012 ◽  
Vol 518-523 ◽  
pp. 352-355
Author(s):  
Hui Liu ◽  
Hong Liang Li ◽  
Meng Xue Wang ◽  
Jing Jing Sang ◽  
Xiu Song Zhao
Keyword(s):  
Aqueous Solution ◽  
Methylene Blue ◽  
Pore Size Distribution ◽  
Pore Size ◽  
Surface Properties ◽  
Weak Base ◽  
Adsorption Ability ◽  
Ph Values ◽  
Model Molecule ◽  
Adsorption Desorption

Methylene blue (MB) was used as model molecule to investigate the effects of surface properties and solvent pH values on the adsorption and desorption (or release) behaviors of mesoporous SBA-15 materials. It was found that the treatment of SBA-15 with a pH 7.8 aqueous solution can enhance the adsorption rate and capacity in comparison with the pristine SBA-15. The effect of pH values on MB releasing from the weak base treated SBA-15 and the pristine one have been studied and been compared in pH values range from 0.5 to 7.0. Both of them showed a maximum releasing rate at about pH 2 and all of the treated SBA-15 samples showed a higher releasing quantity than the pristine ones. The influence mechanisms of base treatment on the adsorption ability and that of pH values on the releasing properties of SBA-15 samples have been analyzed and been discussed based on the composition, the morphology, the surface area and pore size distribution and adsorption/desorption measurements.

Sign in / Sign up

Export Citation Format

Share Document