Simultaneous removal of lead, cadmium, and arsenic Ions from bivalve species using adsorption method

Bivalve such as blood cockle (Tegillarca granosa) feeds by filtering the suspended particle in water including heavy metals and eventually accumulate in the fleshes. Bivalve contaminated with heavy metals might be consumed by human which later could have been exposed to heavy metals toxicity. Therefore, this study was conducted to investigate the effectiveness of adsorption process towards the removal of lead (Pb), cadmium (Cd), and arsenic (As) ions from T. granosa. The findings found that the initial concentration of Pb and As in T. granosa exceeded the permissible limits set by WHO. To remove heavy metals from T. granosa, an adsorption procedure was carried out using lemon and mango peels as natural waste adsorbents. The presence of hydroxyl and carboxylic functional groups in mango and lemon peels was shown in FTIR spectra, which aided in the enhancement of the adsorption process. A series of tests were performed using various parameters such as dosage adsorbents, contact of time, and temperature of reaction. The highest removal percentages of Pb, Cd, and As in T. granosa using lemon peels were 59.65%, 88.89%, and 67.54% respectively. Meanwhile, the maximum removal from T. granosa using mango peels were 70.18% for Pb, 100% for Cd, and 84.71% for As. In conclusion, the adsorption process was effective in removing Pb, Cd, and As in T. granosa. Whereas both lemon peels and mango peels have ability to become effective naturals waste adsorbent in the adsorption process

Preparation and characterization of calcium hydroxyphosphate (hydroxyapatite) from tilapia fish bones and scales via calcination method

Calcium hydroxyphosphate (hydroxyapatite) is a calcium phosphate that is widely used in biomedical application. Hydroxyapatite is an excellent component for bone substitutes for their chemical and structural similarity to natural bone component. In this research, hydroxyapatite was synthesized from tilapia fish bones and scales using calcination method with 3 different temperatures namely 1000 °C, 900 °C and 800 °C. The obtained hydroxyapatite powder was characterized using several techniques such as Fourier-Transform infrared spectroscopy Attenuated total reflection (FTIR-ATR), scanning electron microscope (SEM), proximate analysis and X-ray diffraction (XRD). The results indicated that temperature 1000 °C has the highest weight loss with 21.825 g compared to the temperature 800 °C and 900 °C. From FTIR-ATR analysis, the presence of characteristic peaks for hydroxyl group, phosphate groups and water molecule indicated that the powder were hydroxyapatite. SEM results showed that increasing temperature had led to more dense structure. The hydroxyapatite powder were further analysed for their proximate analysis. The results proved that the highest contents of ash, fat, moisture and crude protein were observed at 1000 °C as compared to 900 °C and 800 °C. Based on this study, it revealed that produced pure hydroxyapatite from natural resources could be a potential candidate for food industry as protein enhancer

Removal of as and cd ions from aqueous solution using biosorption technique

Arsenic (As) and cadmium (Cd) are listed as heavy metals that have contaminated the environment, especially water supplies. Therefore, the goal of this study was to remove heavy metals, particularly As and Cd metal ions, from aqueous solutions by utilizing natural waste adsorbents and at the same time, help in the reduction of waste products. This study was designed to use low-cost and more widely available adsorbents material such as coconut husk and banana peel to remove As and Cd ions in an aqueous solution. The adsorption method was utilized to reduce and remove the As and Cd ions, and their concentrations in an aqueous solution were then determined by Atomic Absorption Spectroscopy (AAS). Various parameters such as types of adsorbents (banana peel and coconut husk), adsorbent dosages (0.1-0.3g), contact time (30-70 minutes), and temperature (25-45°C) were used to carry out the removal process. The FTIR analysis revealed that certain heavy metals were more likely to bind to these adsorbents due to the presence of important functional groups such as hydroxyl (-OH) and carbonyl (C=O). From this study, the optimum removal conditions were 0.1 g dose of adsorbent along with 70 minutes of contact time at a reaction temperature of 25°C. The results revealed that banana peel removed 0.948 mg/L of Cd ions and 0.148 mg/L of As ions from the aqueous solution, suggesting that it was more efficient at removing heavy metals than coconut husk. Meanwhile, Cd ions have a higher affinity (93.9% to 99.9% removal) than As ions (8.3% to 22.2% removal) to adsorb onto the active sites of banana peel and be removed from an aqueous solution. In conclusion, the adsorption technique using natural waste adsorbents can be applied to remove the As and Cd ions from the aqueous solutions. The reduction of these heavy metals' concentration by adsorbents can also help to preserve the quality of water sources under the permissible limit set by WHO

Optimization of basic catalyst with ammoniated polyethylene glycol for the removal of naphthenic acid from petroleum crude oil by Box-Behnken design

Naphthenic acid (NA) removal from petroleum crude oil was investigated and optimized through the utilization of a formulated basic chemical and a basic catalyst. The response surface method (RSM) by Box-Behnken design (BBD) was employed for this purpose. Ammoniated polyethylene glycol (NH3-PEG) and cerium oxide supported on alumina were selected as the basic chemical and basic catalyst, respectively. Synthesizing of the catalyst was conducted through the wet impregnation method, and calcination was performed at temperatures of 400, 700, and 1000 °C. Brunauer-Emmett-Teller analysis (BET), field emission scanning electron microscopy-energy dispersive X-ray (FESEM-EDX), and X-ray diffraction analysis (XRD) were employed for characterizing the catalyst. A preliminary study revealed that the finest catalytic activity was achieved with the calcination of the Ce/Al2O3 catalyst at 1000 °C with a NH3-PEG concentration of 1000 mg/L and a percentage of NH3-PEG/oil mass ratio of 0.40. The optimization of the parameters, which comprise catalyst calcination temperature, concentration of NH3-PEG, and the percentage of NH3-PEG/oil mass ratio on the deacidification of NA, was achieved through the utilization of the response surface method (RSM) by BBD. The optimal conditions were realized at a catalyst calcination temperature of 1,050.54 °C, a NH3-PEG concentration of 853.10 mg/L, and a percentage of NH3-PEG/oil mass ratio of 0.47. With a 0.41 % margin of error, the results from RSM were deemed in good agreement with the experimental values

Catalytic study of Ni/Ce/Al2O3 and Ni/Ca/Al2O3 on the removal of naphthenic acid from petroleum crude oil utilizing sodium thiocyanate in ethanol

The naphthenic acids (NAs) present in the crude oil can lead to the corrosion problems in oil refinery equipment apart from reduces the performances of the oil. In this study, the method to remove NA were done by means of extraction using sodium thiocyanate in ethanol with the aid of Ni/Ca/Al2O3 and Ni/Ce/Al2O3 catalysts at 27 °C reaction temperature. The catalyst was prepared by incipient wetness impregnation method (IWI) and calcined at three different temperature, 800, 900 and 1000 °C respectively. The efficiency of the extraction was affected by the catalyst calcination temperature. Both catalysts calcined at 800 and 900 °C gave total acid number (TAN) value more than 1 mg KOH/g while by using Ni/Ca(10:90)/Al2O3 and Ni/Ce(10:90)/Al2O3 calcined at 1000 °C the TAN value were reduced to 0.28 and 0.65 mg KOH/g respectively. Brunauer-Emmett Teller (BET) result shows both catalysts have large surface area that provide more reaction cites when calcined at 1000 °C. X-ray Diffraction Spectroscopy (XRD) analysis of Ni/Ca/Al2O3 catalyst revealed that the active site was dominated by the Al2O3 species while CeO2 was the active site for Ni/Ce/Al2O3 catalyst. In conclusion, both catalysts reduced the TAN value of acidic crude oil efficiently

Removal of naphthenic acids from high acidity Korean crude oil utilizing catalytic deacidification method

Catalytic deacidification is a fascinating method to decrease the naphthenic acids (NAs) concentration of highly acidic petroleum crude because these acids caused serious corrosion in refinery equipment. Korean crude oil with a total acid number (TAN) of 8.32mgKOH/g was used to test the performance of catalytic deacidification technology. A basic chemical with a dosing of 4% ammonia solution in polyethylene glycol (NH3-PEG) was used as the acid removal agent with concentrations of 100, 500, and 1000mg/L. Cerium oxide, zinc oxide and tin oxide based catalysts supported onto alumina prepared with different calcination temperatures and types of dopants were used to aid in the deacidification reaction. The potential catalyst was characterized by BET, EPR and CO2-TPD for its physicochemical properties. The results showed 93.3% reduction for Korean crude oil using Cu/Ce (10:90)/Al2O3 calcined at 1000°C. This catalyst has the highest BET surface area of 87.12m2/g with higher dispersion of Cu2+ species on the CeO surface detected using EPR spectra and higher total basic site measured using CO2-TPD. These properties contributed to the excellent catalytic performance which remove the NAs in the Korean crude oil and concurrently reduced the TAN value below than one

Enhanced low temperature reaction for the CO2 methanation over Ru promoted Cu/Mn on alumina support catalyst using double reactor system

The bimetallic copper with manganese (Cu/Mn) on alumina (Al2O3) support have been considered as potential catalyst for the carbon dioxide methanation due to the low cost and its unique ability to facilitate the conversion of carbon dioxide (CO2) to methane gas (CH4). However, high operating reaction temperature limits their large scale industrial application. In order to address this challenge, a series of low ruthenium (Ru) content promoted on Cu/Mn supported onto Al2O3 have been design by wet impregnation method. The potential catalyst was tested catalytic acitivity by using single and double reactors. The influences of Cu/Mn ratios and Ru contents on the catalytic activities and physicochemical properties of prepared catalysts were investigated. The addition of Ru can improve the catalytic activity and the basicity of the catalysts surface. As a result, their low-temperature reaction had been enhanced over these doped Ru promoted catalysts. The optimal catalyst was 3Ru60Cu/Mn-Al2O3 where the CO2 conversion reached 98.2% with the methane selectivity of 100% at 220°C by using single reactor. Interestingly, the reaction temperature was reduced at 170°C when using double reactor which the CO2conversion reached 95.6% with the methane selectivity of 100%. The stability test showed that the Ru promoted on Cu/Mn-Al2O3 catalyst maintained its high reactivity after 7 h

Demetallisation of heavy metals from indian mackerel (R. kanagurta) fish

Fish especially Indian Mackerel (R. kanagurta) provides protein, essential fatty acids and essential metals that are needed in the human diet, however high concentration of essential metals will cause adverse health effect towards human. Thus, the removal of heavy metals such as lead (Pb) and copper (Cu) from R. kanagurta (Indian mackerel) by using different types of natural waste adsorbents was implemented in this study. Initial concentration of heavy metals (Pb, Cu) in Indian mackerel (R. kanagurta) fish were above the permissible limit set by World Health Organization and Malaysia Food Regulation 1985. Thus, in this study, corncob and eggshell were applied as natural waste adsorbents to enhance the demetallisation process. The result showed only the corncob able to efficiently remove all the heavy metals in Indian Mackerel (R. kanagurta) up to 78.31% compared to the eggshell, which yielded about 71.34%. Besides, this study proved that using corncob; the Cd metal found to be wholly removed from (R. kanagurta) which met the permissible limit set by WHO and MFR

Effect of acidic and alkaline treatments to methylene blue adsorption from aqueous solution by coconut shell activated carbon

In recent years, pollution from dye wastewater becomes a serious environmental problem due to the high demand and the increment of dye application in textile industry. The purpose of this study was to investigate the potential application of coconut shell activated carbon as methylene blue (MB) removal from aqueous solution. The carbonization process was conducted in temperature range from 300 to 500 °C. For the activation process, two different activating agents namely phosphoric acid, H3PO4 (acid activating agent) and sodium hydroxide, NaOH (basic activating agent) were used. Physical characterization of coconut shell activated carbon (CSAC) was realized by using X-ray diffraction (XRD) for phase identification. After that, the percentage of dye removal was investigated in order to determine the adsorption capacity of the prepared activated carbon. It can be concluded that when the dosage of CSAC increased, the amount of dye removal would also be increased. The results indicated that the coconut shell activated carbon could be employed as a low cost alternative in controlling wide range of sorption processes

Preparation & characterization of microcrystalline cellulose from agriculture waste

In this work, microcrystalline cellulose was prepared from oil palm trunk by water treated fibre process and alkali bleaching. The prepared samples were characterized by using Fourier-transform infrared spectroscopy attenuated total reflectance (FTIR-ATR), Scanning Electron Microscopy (SEM) and X-ray diffraction (XRD). FTIR-ATR spectra analysis indicates the presence of the hydroxyl group, alcohol, alkane/alkene and imine group. XRD patterns revealed the amorphous nature of the samples and the crystallinity index for extracted cellulose is 48.7 %. SEM images showed the fibrous structure of the microcrystalline cellulose with a size of 50 μm. This research proved that the synthesized microcrystalline cellulose could be potentially used as reinforcement in bio composite for better performance and ductility