scholarly journals The Hydrophobic Effect in the Adsorption Process of Alkyltrimethylammonium Bromides on to Activated Carbon

1998 ◽  
Vol 16 (7) ◽  
pp. 557-564 ◽  
Author(s):  
Jinben Wang ◽  
Yao Lu ◽  
Buxing Han ◽  
Ming Dai ◽  
Haike Yan ◽  
...  
Keyword(s):  
Activated Carbon ◽  
Adsorption Process ◽  
Hydrophobic Effect ◽  
Carbon Surface ◽  
Thermodynamic Quantities ◽  
Factors Affecting ◽  
Alkyltrimethylammonium Bromides ◽  
Different Temperatures ◽  
Surface Measurements

This paper describes the hydrophobic effect in the process of adsorption of alkyltrimethylammonium bromides from aqueous solution on to an activated carbon surface. Measurements of the adsorption isotherms of a series of alkyltrimethylammonium bromides with different hydrocarbon tail lengths at the activated carbon surface were carried out. In order to investigate the temperature dependence of the adsorption process, the determination of the adsorption of cetyltrimethylammonium bromide (CTAB) was undertaken at different temperatures in the range 20–60°C. From the experimental results obtained, the relevant thermodynamic quantities have been calculated. The role played by the hydrophobic effect in the adsorption process of cationic surfactants on to activated carbon and the factors affecting the adsorption mechanism were discussed.

Examination of Conditions for the Determination of Carbamate Pesticides in Soils

1992 ◽  
Vol 57 (8) ◽  
pp. 1632-1638 ◽  
Author(s):  
Věra Tatarkovičová ◽  
Zdeněk Stránský
Keyword(s):  
Activated Carbon ◽  
Solvent Extraction ◽  
Soil Type ◽  
Extraction Procedure ◽  
Purification Procedure ◽  
Factors Affecting ◽  
Carbamate Pesticides ◽  
Rp Hplc ◽  
Extracting Solvent

The procedure for the determination of carbamate pesticides in soil was optimized. The following factors affecting the final results were investigated: extracting solvent, extraction procedure, extract purification procedure, and soil type. Triple extraction with acetone and purification of the extract on a two-stage purification column containing an activated carbon-silica gel 1+1 mixture were found optimal. The extracts after treatment were analyzed by RP-HPLC with UV detection. The method developed allows carbamate pesticides in soil to be determined at concentrations in excess of 30 μg kg-1.

scholarly journals Mathematical Model of New Type of Train Buffer Made of Polymer Absorber—Determination of Dynamic Impact Curve for Different Temperatures

Machines ◽  
2018 ◽  
Vol 6 (4) ◽  
pp. 47
Author(s):  
Hristijan Mickoski ◽  
Ivan Mickoski ◽  
Marjan Djidrov ◽  
Filip Zdraveski
Keyword(s):  
Mathematical Model ◽  
Influential Factors ◽  
Dynamic Impact ◽  
Factors Affecting ◽  
Impact Speed ◽  
Environment Temperature ◽  
Different Temperatures ◽  
New Type ◽  
The Impact

Previous experimental knowledge has confirmed that one of the most influential factors affecting the performance of polymer friction absorbers embedded in buffer housing as part of the buffer and chain coupler is the temperature. This paper defines a mathematical model of a friction-type polymer absorber, PMKP-110. The presented mathematical model specifically includes the influence of the environment temperature on the dynamic impact curve for −60 °C and 15 °C. The dependence between the initial pre-tension of the buffer and the ambient temperature is calculated. The model involves an equation of motion for moving parts of the absorber, and the solution of the differential equation is achieved in Matlab. Results are given as diagrams of the impact deformation and impact speed of the polymer block, with assumed zero initial impact speed. The model can be used to analyze the action of the longitudinal forces that occur during transient conditions of the movement of the carriages.

scholarly journals Simultaneous Determination of Nε-(carboxymethyl) Lysine and Nε-(carboxyethyl) Lysine in Different Sections of Antler Velvet after Various Processing Methods by UPLC-MS/MS

Molecules ◽  
2018 ◽  
Vol 23 (12) ◽  
pp. 3316 ◽  
Author(s):  
Rui-ze Gong ◽  
Yan-hua Wang ◽  
Yu-fang Wang ◽  
Bao Chen ◽  
Kun Gao ◽  
...  
Keyword(s):  
Simultaneous Determination ◽  
G Protein ◽  
Processing Methods ◽  
Factors Affecting ◽  
Potential Consumer ◽  
Glycation End Products ◽  
Different Temperatures ◽  
Carboxymethyl Lysine ◽  
Harmful Effects

Nε-(Carboxymethyl) lysine (CML) and Nε-(carboxyethyl) advanced glycation end-products (AGEs) and are frequently used as markers of AGE formation. AGEs, such as CML and CEL, have harmful effects in the human body and have been closely linked to many diseases such as diabetes and uremia. However, details on the contents of CML and CEL after applying different antler velvet processing methods are lacking. In this research, a robust lysine (CEL) are two typical UPLC-MS/MS method has been developed for the simultaneous determination of CML and CEL in various sections of antler velvet processed with different methods. In addition, factors affecting the CML and CEL contents are discussed. The CML contents of antler velvet after freeze-drying, boiling, processing without blood, and processing with blood were 74.55–458.59, 119.44–570.69, 75.36–234.92, and 117.11–456.01 μg/g protein, respectively; the CEL contents were 0.74–12.66, 11.33–35.93, 0.00–6.75, and 0.00–23.41 μg/g protein, respectively. The different contents of CML and CEL in the different samples of antler velvet result from the different interactions of the protein and lysine at different temperatures. These data can be used to estimate the potential consumer intake of CML and CEL from antler velvet and for guiding producers on how to reduce the production of CML and CEL.

scholarly journals OPTIMIZATION OF ULTRASONICALLY ASSISTED ADSORPTION OF Cu(II) ON CARBONIZED AND ACTIVATED WALNUT SHELLS

2018 ◽  
pp. 035
Author(s):  
Dragan Milenković ◽  
Milutin Milosavljević ◽  
Aleksandar Bojić
Keyword(s):  
Activated Carbon ◽  
Adsorption Process ◽  
Model Parameters ◽  
Regression Equations ◽  
Concentration Increase ◽  
Initial Concentration ◽  
Langmuir Adsorption ◽  
Walnut Shells ◽  
Granulated Activated Carbon

The effects of ultrasound (US) on the adsorption process of Cu(II) on granulated activated carbon (GAC), produced by walnut shells, was studied in this paper. Equilibrium results of the adsorption process are tested by Freundlich and Langmuir adsorption isotherms, and their linearization and determination of model parameters k; n; b and Qo. The adsorption capacity of GAC is 1.7 to 3.86 mmol/g with the use of US, and 0.66 to 2.7 mmol /g without the use of US. The increase of specific surface and initial concentration increase the efficacy of adsorption. Acquired mathematical regression equations very well represent experimental results, and the correlation coefficient (R2) is greater than 0.993.

Thermodynamics of Formaldehyde Removal by Adsorption onto Nanosilver Loaded Bamboo-Based Activated Carbon

2017 ◽  
Vol 890 ◽  
pp. 93-97
Author(s):  
Wara Dyah Pita Rengga ◽  
Sri Wahyuni ◽  
Agung Feinnudin
Keyword(s):  
Activated Carbon ◽  
Adsorption Capacity ◽  
Adsorption Process ◽  
Fixed Bed ◽  
Formaldehyde Concentration ◽  
Fixed Bed Column ◽  
Adsorptive Removal ◽  
Formaldehyde Removal ◽  
Different Temperatures ◽  
Formaldehyde Adsorption

The performance of nanosilver loaded bamboo-based activated carbon as an adsorbent used for the adsorptive removal of formaldehyde in the air. The size porous of the active carbon is predominantly on the size of mesoporous and microporous. Adsorption tests have been evaluated in laboratory scale fixed-bed column, at different temperatures and initial formaldehyde concentration. In order to investigate is both equilibrium and thermodynamic aspects. The experimental data was fitted with Langmuir model and fit well with the adsorption capacity of 91-110 mg/g. The increase in temperature reduces the adsorption capacity. The thermodynamic parameters show that the values of ∆Go obtained to confirm the feasibility of activated carbon effective sorbents of formaldehyde. The formaldehyde adsorption process is exothermic and adsorbent has a good affinity to formaldehyde.

Gold Nanoparticles@Activated Carbon Modified Electrode for the Determination of Luteolin

2021 ◽  
Vol 1032 ◽  
pp. 78-83
Author(s):  
Long Yun Dong ◽  
Guan Wan
Keyword(s):  
Gold Nanoparticles ◽  
Activated Carbon ◽  
Modified Electrode ◽  
Carbon Surface ◽  
Good Recovery ◽  
Detection Range ◽  
Coconut Shell Powder ◽  
Shell Powder ◽  
Porous Activated Carbon

In this paper, gold nanoparticles (AuPNs) and activated carbon (AC) modified electrode was used for the determination of luteolin. Porous activated carbon was made from coconut shell powder. The electrode was coated by Porous activated carbon, and then gold nanoparticles were electrodeposited on the porous carbon surface. Electrochemical behavior of luteolin was analyzed by gold nanoparticles@ activated carbon modified electrode. The results show that the detection range of luteolin is 1.8 μmol/L to 10 μmol/L (R2 = 0.9863) with the detection limit of 0.1 nmol/L (3σ/slope), and the recommended method has a good recovery for the detection of luteolin in real urine.

scholarly journals Thermodynamic study of the interactions of salicylic acid and granular activated carbon in solution at different pHs

2017 ◽  
Vol 36 (3-4) ◽  
pp. 833-850 ◽  
Author(s):  
Valentina Bernal ◽  
Liliana Giraldo ◽  
Juan C Moreno-Piraján
Keyword(s):  
Salicylic Acid ◽  
Activated Carbon ◽  
Aqueous Solutions ◽  
Activated Carbons ◽  
Granular Activated Carbon ◽  
Molecular Size ◽  
Carbon Surface ◽  
Immersion Enthalpy ◽  
Inappropriate Use

The inappropriate use of pain medication has led to the appearance of salicylic acid molecules (aspirin’s metabolite excretion) in surface water, which causes problems for the environment. The adsorption process using activated carbon is one of the processes that is used for the removal of organic compounds present in the aqueous phase; however, the percentage of removal depends on the physicochemical properties of the adsorbent and the adsorbate such as: pore size, surface area, surface chemistry, molecular size and solubility. In this work, we have studied the adsorbent–adsorbate interactions through the determination of the immersion enthalpy of the activated carbon in salicylic acid aqueous solutions; due to the solute and activated carbon surface have functional groups capable of ionized with the pH, the adsorption study was carried out at pH 2, 7, and 11. The activated carbons selected for the study were a granular activated carbon and a reduced activated carbon to 1173 K; as the immersion liquid were used salicylic acid aqueous solutions with concentrations between 0.072 mmol/ l and 0.72 mmol/ l, the solutions at pH 2 and 11 were prepared with HCl and NaOH solutions, respectively. It was determined that the immersion enthalpy is between −7.39 J /g and −22.5 J/g for the reduced activated carbon and between −7.63 J/g and −16.73 J/g for the granular activated carbon.

scholarly journals The Fe (II) and Mn (II) adsorption in acid mine drainage using various granular sizes of activated carbon and temperatures

2021 ◽  
Vol 882 (1) ◽  
pp. 012065
Author(s):  
Suliestyah ◽  
Pancanita Novi Hartamai ◽  
Indah Permata Sari ◽  
Edwardo Alexander
Keyword(s):  
Activated Carbon ◽  
Acid Mine Drainage ◽  
Adsorption Process ◽  
Mine Drainage ◽  
Atomic Absorption Spectrophotometry ◽  
Carbon Surface ◽  
Acid Mine ◽  
Bet Method ◽  
Fe And Mn ◽  
Mn Concentrations

Abstract Acid mine drainage (AMD) from coal mining activities contains Fe and Mn concentrations that often exceed environmental quality requirements. This study aims to determine the effect of the coal material size and temperature on the adsorption process of Fe and Mn metals contained in AMD using activated carbon made with a composition of 60% coal and 40% ZnCl2. For characterizing activated carbon, surface morphological was analyzed using SEM method, and surface area was analyzed using BET method. Meanwhile, for measuring Fe and Mn concentrations, the researchers used atomic absorption spectrophotometry. The adsorption process was carried out with various granular sizes of activated carbon (20, 28, 35, 48 and 60 mesh) and temperature (25, 35, 40, 45 and 50°C). The results showed that the maximum adsorption of Fe was 100% occurred in the treatment with an activated carbon size of 60 mesh and a temperature of 45°C, while the maximum adsorption of Mn was 11.91% in the treatment with an activated carbon size of 60 mesh and a temperature of 50°C. Furthermore, the activated carbon of coal is highly effective as an adsorbent for Fe in AMD waste but less effective for Mn.

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