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Effective Removal of Indigo Carmine in Aqueous Solutions using a Low-Cost Adsorbent Developed from Corn Husk Waste: Synthesis, Batch, and Optimization Studies 全文
2023
Handayani, Tuti | Emriadi, Emriadi | Deswati, Deswati | Ramadhani, Putri | Zein, Rahmiana
Acid-activated corn husk waste (CHW) was used to investigate the adsorption mechanism of Indigo Carmine (IC) dye from an aqueous solution. The effect of different operating parameters such as pH (1-7), initial IC dye concentration (40-400 mg/L), contact time (5-75 min), and heating temperature (25–200 °C) was measured on the removal of IC dye by the CHW. The maximum uptake of IC dye was observed at an initial pH of 2. The maximum capacity of 13.57 mg/g and the maximum dye removal of 89.01 % in wastewater. The adsorbents were characterized using Fourier Transforms Infrared Spectrophotometry (FTIR), Scanning Electron Microscopy (SEM), Brunauer-Emmett-Teller (BET) surface area analysis, X-ray Fluorescence (XRF), and Thermogravimetry Analysis. The characterization process reveals the differences in adsorbent characteristics before and after the adsorption processes. The Langmuir showed the best fitting (R2 = 0.977) and described multilayer adsorption on diverse surfaces. The pseudo-second-order kinetic model best correlated with the experimental data (R2 = 0.981). Thermodynamics revealed that adsorption was favorable spontaneous and exotherm. The study's results indicated that using CHW as a low-cost adsorbent to treat IC dye was efficient and beneficial to the environment.
显示更多 [+] 显示较少 [-]Effect of Water Soluble Organic Carbon (WSOC) and Polycyclic Aromatic Hydrocarbons (PAHs) emitted by BioChar from the Rubber Sheets Processing Sewage Sludge Combustion 全文
2023
Lakachaiworakun, Putipong | Dangwilailux, Panya | Eakvanich, Visit | Kalasee, Wachara
The total particle mass concentration, size distribution, pH form, polycyclic aromatic hydrocarbons (PAHs) value, the concentration of total Benzo[a]pyrene Toxic Equivalence (BaPTE) and water-soluble organic carbon (WSOC) of smoke particles from the rubber sheets processing sewage sludge biochar burning were studied. In this work, the temperature was measured at 500 mm above the fire base by using K-type thermocouples and a continuously data logger. The result showed that the measured temperature value increased when decreasing the biochar moisture content. The highest average total smoke particle mass concentration values at the initial burning time was found to be 17.53 to 35.27 mg/m3 and then it was persistently reduced until the 60th minute, when the burning was stopped. The pH of biochar's smoke particles was higher than it was before combustion. The total smoke particle mass concentration, the mass median aerodynamic diameter (MMAD) and PAHs values decreased with increasing burning period and decreased the biochar moisture content. The largest BaPTE emission was observed at the highest moisture content, which was within the range of the greatest particle mass (less than 0.43 micron) in an initial combustion period. This value was about 60% that of a given the total value of BaPTE concentration. Meanwhile, the amount of PAHs, the BaPTE concentration and WSOC were depended on the smoke particle number, moisture content and combustion period.
显示更多 [+] 显示较少 [-]Natural Biodegradation Rates of Single-Use Blended Bioplastic Packaging Nylon Entrenched In Freshwater and Marine Water Environments of the Tropics 全文
2023
Dada, Omotola | Bada, Adeola | Okorodo, Emmanuel
The biodegradation rates of single-use blended bioplastic packaging nylon, nylon 6, and cellulose polymer were assessed in aquatic environments in an attempt to identify real biodegradable bioplastics (RBB). The natural biodegradation rates of the test samples in freshwater and marine water were assessed by respirometric method following the procedure of the American Standard Testing and Materials. The experimental design was arranged thrice in a completely randomized design of 2x4x3. The physicochemical parameters were obtained using the standard methods while the rates of biodegradation were obtained by titration method. Data obtained were analyzed using descriptive statistical method. At the end of 120 days, there were steady increase in the rates of biodegradation of cellulose and bioplastic samples across the fourth month in both freshwater and marine water. However, the rate of biodegradation in marine water were higher than in freshwater following the trend cellulose in marine (342 %) > cellulose in freshwater (259%) > bioplastics packaging nylon in marine (193%) > bioplastics packaging nylon in freshwater (175%). For nylon 6, the rate (-14) of retardation in the biodegradation process in Nylon 6 soaked in marine water is greater than that of Nylon 6 soaked in freshwater (-13). Consequently, nylon 6 was recalcitrant to biodegradation both in freshwater and marine water. The study concluded that the blended bioplastic packaging nylon is a real biodegradable bioplastic and could be suggested as a feasible and environmentally-friendly option to replace traditional plastics in the society.
显示更多 [+] 显示较少 [-]Integrated Environmental Assessment of Unsustainable Exploitation and Pollution of Shared Water Resources in Transboundary Basins of Semi-arid and Arid Regions. Case Study: Tigris-Euphrates River Basin 全文
2023
Zebardast, Lobat | Balist, Jahanbakhsh | Karimi, Hazhir
River basins perform the crucial role of providing water resources, especially in arid regions. Due to the nature of interconnection, human interventions and natural events will cause cumulative impacts on the downstream parts of river basins. The aim of this research is to identify and evaluate the impacts of interventions and changes occurring in the upstream of the Tigris-Euphrates River Basin on the downstream parts and provide strategies to reduce and control those effects. To achieve this purpose, multi-scaled investigation of the changes and dynamics of the land cover was performed and the causes and consequences of these changes were investigated using the Driving force-Pressure-Sate-Impact-Response (DPSIR) framework. The results displayed an increase in the area of artificial lakes and agricultural lands and a decline in the area of rangelands and natural wetlands, especially in the downstream of the basin. The state of the ecosystem was under the influence of Driving forces such as population and industrial growth and political competitions of the littoral states, which led to pressure on the limited water resources and development of water management and control projects. The overall trends of changes in the state of the environment had created impacts on the ecosystem and communities that required urgent responses from the riparian countries. Finally, to foster water cooperation instead of non-constructive completions in this region, a framework was developed with an emphasis on creating a union of riparian countries and using their scientific potentials to provide effective and impartial solutions.
显示更多 [+] 显示较少 [-]Assessment of Non-Ionizing Radiation Emissions from Cell Phone Towers 全文
2023
Alkhalidi, Murtadha | Al-Shakban, Mundher | Kalifa, Ahmed | A. Abdul Ridha, Hamzah
People’s growing anxiety, and fear of the issue of a large number of mobile phone towers, as well as the lack of studies dealing with this issue at the level of the country in general, and the governorate in particular. All these reasons led to the issue of non-ionizing rays given off by mobile telephone masts on the table of worries about how this radioactivity will affect people's health. Non-ionized radiation emissions were measured by taking 280 readings for the three frequency packets 900, 1800, and 1840 MHz, which are sequential-Global System Mobile (GSM), of 20 cell phone towers in the Al-Amara, the city center of Misan prefecture. Four readings were collected for each frequency, with the highest value for overlap between electromagnetic field and frequency being chosen. A selective Radiation Meter (SRM-3006) was the device used in this study. It was found that the amount of non-ionizing radiation emitted by the towers taken in the study, and for the frequencies (900, 1800, and 1840 MHz) was, in a successive manner (309 × 10-8, 7 ×10-8, and 1109×10-7 MHz). Thus, the measured values of radiation were less than the surveyed limit (4×10-1 μW/cm2) provided for by the law of Iraq’s Determinants for Non-ionized Radiation Emissions (IDNREs).
显示更多 [+] 显示较少 [-]Prioritizing Local Biomass Resources for Biofuel Production by a Fuzzy Hybrid Decision Making Approach (The Case of Hormozgan Province in Iran) 全文
2023
nohegar, Ahmad | Alavi Naeini, Mina | Alavi naeini, Ali
In recent years, increasing in energy demand and the importance of using energy with minimum green- house gas emission (GHG) leads researchers to study about renewable energy resources such as biomasses. Biomasses can be converted to biofuels by applying the appropriate technologies. In this study, a hybrid group fuzzy multi-criteria decision making (MCDM) approach based on step-wise weight assessment ratio analysis (SWARA), technique for order preference by similarity to ideal Solution (TOPSIS), additive ratio assessment (ARAS), weighted aggregated sum product assessment (WASPAS) and simple additive weighting (SAW) in the fuzzy environment is applied to rank biomasses in the case of Hormozgan province in Iran, because of being a coastal area and the access to different types of first, second and third generation resources of biofuel. After ranking these resources by mentioned methods, two aggregated multi-criteria decision making (MCDM) methods (mean rank method and Copeland method) are employed to prioritize these biomasses. Results of mean rank show that municipal solid wastes (MSW), fish wastes and microalgae have the minimum average rank, respectively and the results of Copeland method show that MSW, fish wastes and microalgae have the maximum (wins-loses), respectively. So, these biomasses are the most suitable ones in biofuel production in this province.
显示更多 [+] 显示较少 [-]Biochar Derived from the Husk and Straw of Rice (Oryza sativa L.) Produced via Low-Temperature Pyrolysis as an Effective Adsorbent for Pb (II) Removal 全文
2023
Chaijak, Pimprapa | Michu, Panisa | Thipraksa, Junjira | Kongthong, Alisa
Pyrolysis is a promising thermochemical conversion process that transforms biomass into biochar, a carbon-rich solid material, in an oxygen-limited environment. This study focuses on the utilization of rice byproducts, namely rice straw and rice husk as feedstock for biochar production through low-temperature pyrolysis. The aim is to explore the potential of these biochars as cost-effective adsorbents for removing metal contaminants from aqueous solutions, with a particular emphasis on Pb(II) removal. Physicochemical properties of the biochars produced at a low temperature of 300 °C were thoroughly investigated, including surface morphology and their adsorption capacity for Pb(II). Remarkably, the rice straw biochar (RSB) produced at 300 °C exhibited exceptional Pb(II) adsorption capacity, with a value of 390.10±0.30 mg/g, and demonstrated a high Pb(II) removal efficiency of 96.10±0.30% when modified with 30% w/w H2O2. A crucial aspect of this study lies in the evaluation of the cost-effectiveness of the biochar production process, particularly when compared to commercially available adsorbents. By demonstrating the potential of rice byproduct-derived biochar as an efficient Pb(II) biosorbent in aqueous environments, this work not only provides new insights into the preparation of biochar using low-temperature pyrolysis but also offers a viable and economical solution for metal-contaminated water treatment. The findings of this research contribute to the field of sustainable waste utilization and highlight the significant potential of rice byproduct-based biochar as an environmentally friendly adsorbent for heavy metal removal.
显示更多 [+] 显示较少 [-]Detection of Microplastics in Drinking Water Treatment Plants in Baghdad City/Iraq 全文
2023
H. Sultan, Hassan | Abdul Wahab Shaker Al-Aadhami, Mohammad | Nihad Baqer, Noor
Microplastics are an emerging environmental pollutant detected in different environments, but studies in Iraq are rare, if not nonexistent. Our research aims to detect the presence of microplastics in raw water and drinking water treatment plants in Baghdad. Water samples were collected (1 liter per sample) from four drinking water treatment plants: Al-Fahama station, Al-Fath Al-Mubin station, Al-Dora station, and Al-Madaen station, which receive water from the Tigris River. The microplastic shape was determined by a fluorescent microscope examination after staining with Nile dye. FTIR spectrophotometer used to determine microplastic compounds. The results showed, according to FTIR examination, that the most critical types of microplastic compounds in water samples were Nylon, Polycarbonate, High-density polyethylene, Polystyrene, Polyamide, Polyethylene terephthalate, and Polyurethane, and Microplastics number were (17-62 MPs /L) in raw water, while in drinking water were (9-40 MPs/L). The fibers form is the predominant form of microplastics in natural and drinking for stations: Al-Fahamah (91.6%, 66.6% respectively), Al-Fath Al-Moubin (58.8%, 77.7% respectively ), Al-Doura (65.3%, 52.5% respectively), Drinking water in Al-Madaen station (40.0%). At the same time, the spherical shape is predominant in the raw water of Al-Madaen station (82.2%).In conclusion, the current study indicated the pollution of drinking water treatment plants with microplastics.
显示更多 [+] 显示较少 [-]Sustainable Energy Transition for Cities Based on Long-Term Planning Supported by a Fuzzy Cognitive Map 全文
2023
Eftekhar, Alireza | Yazdanpanah Dero, Qiuomars | Zaker Esfehani, Alireza
The present study was aims to explore resilience and transformation capabilities and explore their applicability in the field of energy. It focuses especially on the role of the cognitions of stakeholders and decision-makers in the uptake and management of sustainability transitions. Fuzzy cognitive mapping (FCM) is used to aggregate different stakeholders’ views on the functioning and performance of the urban energy system of the city of Tehran. In the case of Tehran, the urban energy network is analyzed in terms of resilience and transformability by studying the degree of connectivity and its influence on both system characteristics. Three scenarios of policy options are simulated to weight their outcomes in terms of sustainability, Scenario A: Optimization of economic incentives; Scenario B: Strong education and awareness campaigns; and Scenario C: Stronger local institutional initiatives. Scenario A shows a potential perverse effect if the current economic structure is maintained, even if the economic crisis is overcome. Combining Scenarios B and C provides the best results in terms of sustainability. This suggests that successful transformation in cities should pivot on a combination of top-down and bottom-up actions to unlock resilient but unsustainable states, and that special care needs to be taken when managing highly connected and/or influential elements of the system, as contextual dependencies might hinder the agency of change, particularly in the context of cities. Network characteristics, such as connectivity, can be useful indicators to inform resilience and transformation management, although the double-edge sword nature of connectivity should be noted.
显示更多 [+] 显示较少 [-]Use of Eggshell as a Low-Cost Alternative Adsorbent for Elimination of Fluoride from Groundwater 全文
2023
Assami, Zakaria | Messaitfa, Amar
This paper aims to study the possibility of providing a low-cost alternative for the adsorbents used in the fluoride adsorption from water by using eggshells. Indeed, eggshells were used as an adsorbent for fluoride adsorption from a drinking groundwater sample containing (2.14 mg/l) of fluoride. The eggshells were crushed and sieved into three particle sizes (0.2, 0.5, and 1mm) and then heated at different temperatures ranging from 100 to 250°C. XRD, FT-IR, pHpzc, and TG/DTA analysis were used for the characterization of the adsorbents. Adsorption batch experiments were carried out to determine the adsorption capacity of eggshell powder such as, particle size, preparation temperature, contact time, and adsorbent dose. A spectrophotometer UV-VIS was used to assess fluoride removal efficiency. The eggshell powder heated at 250°C with 0.2mm of particle size was found to be the most efficient adsorbent, with a maximum fluoride removal efficiency of 51.4%, a maximum adsorption capacity of 0.052mg/g, and a residual fluoride concentration of 1.1mg/l within 150 minutes. The data of the adsorption kinetic on ES250°0.2 were successfully fitted with the pseudo-second-order model with a satisfying coefficient of determination (R2=0.993). The results of the intra-particle diffusion model showed a multi-linearity, revealing that the diffusion of fluoride into the adsorbent was by two stages with diffusion rate constants of Ki = 0.007 (mg /g/min1/2) and Ki = 0.001(mg /g/min1/2) for the first and second stage respectively. An adsorbent dose of 1.5g and 1 hour of contact time were sufficient to decrease fluoride concentration from 2.14 to 1.1mg/l.
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