scholarly journals Application of adsorption process for phenolic compounds removal from aqueous environments: A systematic review

2016 ◽  
Vol 18 (1) ◽  
pp. 146-163 ◽  
Keyword(s):  
Phenolic Compounds ◽  
Low Cost ◽  
Coke Oven ◽  
Carbon Adsorbents ◽  
Toxic Substances ◽  
Physical Treatment ◽  
Advantages And Disadvantages ◽  
Aqueous Environments ◽  
Adsorption Processes ◽  
Paper And Pulp

<p>Wastewater from various types of industries such as synthetic resins, plywood industries, paper and pulp, gas and coke oven plants, paints, coal gas, tanning, textile, plastic, rubber, pharmaceutical, petroleum and mine discharges, contain different types of phenols. Phenolic compounds are toxic substances and some are known or suspected carcinogens. Therefore it is important to remove phenol and phenolic compounds from contaminated industrial aqueous streams before discharged into any water bodies. Adsorption of phenol and its derivatives from aqueous solution by activated carbon is one of the most investigated of all liquid phase applications of carbon adsorbents. Several adsorbents have been used for treatment of wastewater and removal of phenolic compounds. Literature contains various adsorption processes and adsorbents such as pistachio nut shell ash, Moringa peregrina tree shell ash, agricultural fibers, red mud, low cost clay, olive mill waste, natural zeolites, rubber seed coat, peat, fly ash, bentonite and &hellip; which have been used for the removal of phenol and its derivatives. Any of chemical, biological and physical treatment processes has its own advantages and disadvantages. It is worth mentioning that economic aspects of these processes are important, for example biosorption were found to be effective methods with scope for further research in this field in terms of cost effectiveness and regeneration. At present study various adsorbents used by the authors of this article and other researchers for phenol and its derivatives from aqueous environments have been reported and summarized. Additionally, more research is needed to find the practical utility of low-cost adsorbents on commercial scale.</p>

scholarly journals Phenolic Compounds: Health Effects and Its Removal From Aqueous Environments by Low Cost Adsorbents

Health Scope ◽  
2013 ◽  
Vol 2 (2) ◽  
pp. 65-66 ◽  
Author(s):  
Edris Bazrafshan ◽  
Ferdos Kord Mostafapour ◽  
Hossein Jafari Mansourian
Keyword(s):  
Phenolic Compounds ◽  
Health Effects ◽  
Low Cost ◽  
Aqueous Environments

Demonstration of environmental chemistry with microscale chemistry and a low-cost four-led based photom

2018 ◽  
Vol 16 (4) ◽  
pp. 510
Author(s):  
Wai Kin Kee ◽  
Wing Hong Chan
Keyword(s):  
Phenolic Compounds ◽  
Environmental Chemistry ◽  
Low Cost ◽  
Light Sources ◽  
Electrochemical Degradation

<span>In this article, a four-LED based photometer, in which four LEDs are used as light sources, are demonstrated to be a useful instrument for the study of pollution problems caused by phenols and of their remediation by electrochemical degradation method and the iron (II) catalyzed homogeneous Fenton’s reaction. The fate of phenols can be monitored by the photometer via the 4-aminoantipyrine method. The results revealed that the latter method was a superior method to treat the phenolic compounds.</span>

scholarly journals Reinforcement of Recycled Aggregate by Microbial-Induced Mineralization and Deposition of Calcium Carbonate—Influencing Factors, Mechanism and Effect of Reinforcement

Crystals ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 887
Author(s):  
Chunhua Feng ◽  
Buwen Cui ◽  
Haidong Ge ◽  
Yihong Huang ◽  
Wenyan Zhang ◽  
...  
Keyword(s):  
Calcium Carbonate ◽  
Global Economy ◽  
Low Cost ◽  
High Water ◽  
Strengthening Mechanism ◽  
Recycled Aggregate ◽  
Strengthening Effect ◽  
Calcium Carbonate Precipitation ◽  
Environmental Friendliness ◽  
Advantages And Disadvantages

Recycled aggregate is aggregate prepared from construction waste. With the development of a global economy and people’s attention to sustainable development, recycled aggregate has shown advantages in replacing natural aggregate in the production of concrete due to its environmental friendliness, low energy consumption, and low cost. Recycled aggregate exhibits high water absorption and a multi-interface transition zone, which limits its application scope. Researchers have used various methods to improve the properties of recycled aggregate, such as microbially induced calcium carbonate precipitation (MICP) technology. In this paper, the results of recent studies on the reinforcement of recycled aggregate by MICP technology are synthesized, and the factors affecting the strengthening effect of recycled aggregate are reviewed. Moreover, the strengthening mechanism, advantages and disadvantages of MICP technology are summarized. After the modified treatment, the aggregate performance is significantly improved. Regardless of whether the aggregate was used in mortar or concrete, the mechanical properties of the specimens were clearly improved. However, there are some issues regarding the application of MICP technology, such as the use of an expensive culture medium, a long modification cycle, and untargeted mineralization deposition. These difficulties need to be overcome in the future for the industrialization of regenerated aggregate materials via MICP technology.

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

Molecules ◽  
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.

scholarly journals Equilibrium and Kinetic Study of Anionic and Cationic Pollutants Remediation by Limestone–Chitosan–Alginate Nanocomposite from Aqueous Solution

Molecules ◽  
2021 ◽  
Vol 26 (9) ◽  
pp. 2586
Author(s):  
Inas A. Ahmed ◽  
Ahmed H. Ragab ◽  
Mohamed A. Habila ◽  
Taghrid S. Alomar ◽  
Enas H. Aljuhani
Keyword(s):  
Physical Adsorption ◽  
Low Cost ◽  
Freundlich Isotherm ◽  
Entropy Change ◽  
Sem Images ◽  
Bet Analysis ◽  
Adsorption Processes ◽  
Equilibrium Data ◽  
Pseudo Second Order ◽  
Multilayer Formation

In this work, low-cost and readily available limestone was converted into nanolimestone chitosan and mixed with alginate powder and precipitate to form a triple nanocomposite, namely limestone—chitosan–alginate (NLS/Cs/Alg.), which was used as an adsorbent for the removal of brilliant green (BG) and Congo red (CR) dyes in aqueous solutions. The adsorption studies were conducted under varying parameters, including contact time, temperature, concentration, and pH. The NLS/Cs/Alg. was characterized by SEM, FTIR, BET, and TEM techniques. The SEM images revealed that the NLS/Cs/Alg. surface structure had interconnected pores, which could easily trap the pollutants. The BET analysis established the surface area to be 20.45 m2/g. The recorded maximum experimental adsorption capacities were 2250 and 2020 mg/g for CR and BG, respectively. The adsorption processes had a good fit to the kinetic pseudo second order, which suggests that the removal mechanism was controlled by physical adsorption. The CR and BG equilibrium data had a good fit for the Freundlich isotherm, suggesting that adsorption processes occurred on the heterogeneous surface with a multilayer formation on the NLS/Cs/Alg. at equilibrium. The enthalpy change (ΔH0) was 37.7 KJ mol−1 for CR and 8.71 KJ mol−1 for BG, while the entropy change (ΔS0) was 89.1 J K−1 mol−1 for CR and 79.1 J K−1 mol−1 BG, indicating that the adsorption process was endothermic and spontaneous in nature.

scholarly journals Development and Characterization of a Novel Low-Cost Water-Level and Water Quality Monitoring Sensor by Using Enhanced Screen Printing Technology with PEDOT:PSS

Micromachines ◽  
2020 ◽  
Vol 11 (5) ◽  
pp. 474 ◽  
Author(s):  
Bei Wang ◽  
Manuel Baeuscher ◽  
Xiaodong Hu ◽  
Markus Woehrmann ◽  
Katharina Becker ◽  
...  
Keyword(s):  
Water Quality ◽  
Water Level ◽  
Sheet Resistance ◽  
Screen Printing ◽  
Low Cost ◽  
Conductive Polymer ◽  
Water Quality Monitoring ◽  
Physical Treatment ◽  
Printing Technology ◽  
Screen Printing Technology

A novel capacitive sensor for measuring the water-level and monitoring the water quality has been developed in this work by using an enhanced screen printing technology. A commonly used environment-friendly conductive polymer poly(3,4-ethylenedioxythiophene):poly (styrenesulfonate) (PEDOT:PSS) for conductive sensors has a limited conductivity due to its high sheet resistance. A physical treatment performed during the printing process has reduced the sheet resistance of printed PEDOT:PSS on polyethylenterephthalat (PET) substrate from 264.39 Ω/sq to 23.44 Ω/sq. The adhesion bonding force between printed PEDOT:PSS and the substrate PET is increased by using chemical treatment and tested using a newly designed adhesive peeling force test. Using the economical conductive ink PEDOT:PSS with this new physical treatment, our capacitive sensors are cost-efficient and have a sensitivity of up to 1.25 pF/mm.

NOx Emissions in a Steel Reheat Furnace Firing By-Product Fuels

2001 ◽  
Author(s):  
Bradley R. Adams ◽  
Dave H. Wang
Keyword(s):  
Low Cost ◽  
Nox Reduction ◽  
Coke Oven ◽  
Cfd Modeling ◽  
Stoichiometric Ratio ◽  
Nox Emissions ◽  
Confined Space ◽  
Nox Formation ◽  
Reheat Furnace ◽  
Bottom Zone

Abstract A DOE-funded program was used to understand the mechanisms that control the formation of NOx during the combustion of steelmaking by-product fuels and to investigate possible low-cost control options to minimize the NOx emissions. This paper discusses the CFD modeling results of NOx emissions in a reheat furnace. The reheat furnace has a total of 20 burners distributed over three firing zones. The furnace is fired at a rate of 250 × 106 Btu/hr and an overall stoichiometric ratio of 1.06 (fuel lean). Fuels with heating values of approximate 500 Btu/SCF were examined, including coke oven gas (COG), blast furnace gas (BFG) and a blend of COG, BFG, natural gas (NG) and nitrogen. A good range of process variables was modeled to examine effects of fuel type, air preheat, stoichiometric ratio, firing rate and burner stoichiometry distribution on NOx emissions. Modeling results indicated that NOx formation in the reheat furnace is dominated by thermal NO, with some variation depending on the fuel fired. Temperature profiles showed an effective separation of the furnace interior into top and bottom zones as a result of the steel slab barrier. Higher temperatures characterized the bottom zone and elevated NOx levels as a result of the confined space and enhanced fuel air mixing provided by the slab supports. Results also showed that reburning of NOx plays a significant role in final NOx emissions with 30–40% of NOx formed being reduced by reburning in most cases. Modeling identified that operating the side burners in each burner zone slightly substoichiometric (while maintaining the overall furnace stoichiometry at 1.06) provided significant NOx reduction via reburning. NOx reductions of 23% and 30% were predicted when firing with COG and COG-NG-Air fuels, respectively. Overall furnace exit temperatures and heat flux profiles were not significantly affected by the biased firing.

Overview on the Liquid Metal Battery for Grid-Level Large-Scale Energy Storage

2016 ◽  
Vol 723 ◽  
pp. 572-578
Author(s):  
Li Fu ◽  
Qi Chi Le ◽  
Xi Bo Wang ◽  
Xuan Liu ◽  
Wei Tao Jia
Keyword(s):  
Energy Storage ◽  
Liquid Metal ◽  
Large Scale ◽  
Low Cost ◽  
Advantages And Disadvantages ◽  
Comprehensive Comparison ◽  
Development And Utilization ◽  
Working Principle ◽  
Liquid Metal Battery ◽  
Grid Level

In recent years, the development and utilization of renewable generation have attracted more and more attention, and the grid puts forward higher requirements to the energy storage technology, especially for security, stability and reliability. The liquid metal battery (LMB) consists of two liquid metal electrodes and a molten salt electrolyte, which will be segregated into three liquid layers naturally. Being low-cost and long-life, it is regarded as the best choice for grid-level large-scale energy storage. This paper describes the main structure and working principle of the LMB, analyzes the advantages and disadvantages of the LMB when compared with the traditional batteries, and explores the feasibility and economy when it is used as a kind of large-scale energy storage applied in the power grid. The paper also makes a comprehensive comparison on the performance of several LMBs, and points out the LMB’s research and development in the future.

scholarly journals The effective removal of heavy metals from water by activated carbon adsorbents of Albizia lebbeck and Melia azedarach seed shells

2019 ◽  
Vol 15 (No. 1) ◽  
pp. 30-37 ◽  
Author(s):  
Mohib Ullah ◽  
Ruqia Nazir ◽  
Muslim Khan ◽  
Waliullah Khan ◽  
Mohib Shah ◽  
...  
Keyword(s):  
Activated Carbon ◽  
Toxic Metals ◽  
Low Cost ◽  
Future Generations ◽  
Carbon Adsorbents ◽  
Melia Azedarach ◽  
Albizia Lebbeck ◽  
Effective Removal ◽  
Removal Of Heavy Metals ◽  
Concentrated Solution

The removal of toxic metals like lead (Pb) and cadmium (Cd) is very urgent keeping their hazardous effects in view. In this work, seeds of Albizia lebbeck and Melia azedarach trees were converted into activated carbon adsorbents and applied for the adsorptive removal of Pb and Cd metals from an aqueous solution. The as prepared adsorbents were characterised by Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The removal efficiencies of both metals were strongly dependent on their initial concentration, contact time, pH, temperature and the quantity of adsorbents. 0.2 g of both adsorbents removed respectively 75 and 62% Pb and 77 and 66% Cd from from 100 ml of a 40 mg/l concentrated solution in 120 min at pH 5 and a temperature of 20°C. Both the Freundlich and Langmuir isotherms were well fitted to the experimental data. We believe that this work will provide a convenient way to synthesise low cost activated carbon adsorbents for the remediation of highly toxic metals from wastewater to safeguard our environment for future generations.

scholarly journals Development of a low-cost X-band meteorological radar

2021 ◽  
Author(s):  
Jan Hrach
Keyword(s):  
Material Selection ◽  
Low Cost ◽  
Technology Selection ◽  
Advantages And Disadvantages ◽  
Radar Network ◽  
X Band ◽  
Spatially Distributed ◽  
Commercial Off The Shelf ◽  
Slotted Waveguide ◽  
Small Team

&lt;p&gt;We have undertaken a journey to develop a small X-band radar based on widely available commercial off-the-shelf (COTS) components. We have evaluated various radar transmitters, antenna and radome designs and sizes and we are currently operating the second-largest radar network in Europe, spanning 5 countries and consisting of 30 radars.&lt;/p&gt;&lt;p&gt;The final solution can be deployed by a small team in two days and operated without supervision with negligible maintenance and recurring costs. With approximately 120 kilometers of effective range and high refresh rate, it might be a good fit as an early warning radar, for areas with no current radar coverage or to fill gaps in larger networks; however, due to some limitations of the X band, namely higher attenuation in spatially distributed rain, it may not be a replacement of long-range observation radars.&lt;/p&gt;&lt;p&gt;In this work, we present an overview of our undertakings, technical solutions we have chosen and problems we have encountered. First, we cover transmitter technology selection, and discuss advantages and disadvantages of currently available magnetron and solid-state transmitters. Then we show the evolution of our antenna design, from 1-dimensional slotted waveguide to parabolic antennas with tapered beam.&amp;#160;&lt;/p&gt;&lt;p&gt;With large parabolic antennas, another problem arises: the mechanics of the radar cannot cope with the additional weight and angular momentum, thus we had to develop various mechanical supports and a custom rotator. This rotator can also tilt the antenna, effectively adding volumetric scanning; the tilting is also needed to cope with non-ideal radar locations, where the horizon is partially obscured, which are unfortunately common for a radar network with limited budget. Finally, we discuss design and material selection of our custom radomes, and present an overall experience with everyday running and maintaining the network.&lt;/p&gt;

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