ORIGINAL_ARTICLE
Water-Hyacinth from Nile River: Chemical Contents, Nutrient Elements and Heavy Metals
SAMPLES of water-hyacinth were collected from the main stream of Nile River near the location of El-Kanater El-Khayria. Plant samples were taken at three intervals during March, August and December during the years 2014 and 2015 to study the seasonal variation. The harvested plants were divided into leaves, stems and roots and were subjected for general analysis of crude protein, ash, crude fat, fibers and nitrogen free extract. Meanwhile, sugars and carbohydrates were determined in the different plant samples. Plant stems showed maximum reducing sugars content. On the other hand, leaves demonstrated the highest level of both non-reducing and total sugars. The mineral analysis revealed that sodium, potassium, magnesium and calcium were found in relatively higher level. Iron, zinc and manganese were within moderate concentration. Copper, lead and cobalt detected in plant tissues were in minor amounts. Results indicated that the level of the determined chemical contents depended mainly on the sampling date and the plant organ.
https://ejchem.journals.ekb.eg/article_934_2bbfec6faa95d6aa2b2a143b0d1f2576.pdf
2016-04-30
131
143
10.21608/ejchem.2016.934
ORIGINAL_ARTICLE
Mathematical Modeling for Performance Prediction of a Humidification – Dehumidification Solar Water Desalination System in Egypt
A SIMPLE water desalination system using humidification–……...dehumidification process (HDH) enhanced with solar energy was theoretically studied. In the presented system, a double jacket solar water storage tank was used to heat the saline water in a separate independent circuit. A natural circulation solar water cycle between the flat plate collector and the storage tank was introduced to prevent salt scales formation inside the internal boundary layers of the flat plate collector tubes and heating system network. The humid air in the atomization chamber was collected on the condenser surface that cooled by water using thermoelectric refrigeration technique. This refrigerator was powered by a DC electric source provided by a solar photovoltaic module to maximize the water yield. The simulation model was built using the local meteorological conditions of Cairo, Egypt (30° 2' N latitude, 31° 14' E longitude). Results showed that the daily production of condensed water depended on the flow rate and temperature of saline water in addition to air mass flow rate and its pressure. It is found that the maximum productivity of the system is achieved in summer season with a value of 64.3 L/day and it is found that each kWh/m2/day falling on the collector surface produced 7.9 L/day. Although the produced quantity of desalinated water is small, yet it can help inhabitants especially in rural and remote areas where potable water is unavailable to be kept survived. Moreover, this system could be replicated to produce more desalinated water for inhabitants demand. As Egypt enjoys long coastal area of about 2500 km in length as well as abundant solar energy most time of the year will encourage the Egyptian government to install several solar water desalination plants with several technologies. One of the most promising and simple technologies is the HDH Process.
https://ejchem.journals.ekb.eg/article_937_5dd416d0a1c0137b2504130650242517.pdf
2016-04-30
145
162
10.21608/ejchem.2016.937
Water desalination
solar energy
Humidification–dehumidification
Thermoelectric refrigeration and Heat exchanger
ORIGINAL_ARTICLE
Synthesis,Mechanisms and Different Applications of Mesoporous Materials Based on Silica and Alumina
SILICATE mesoporous materials have received widespread interest …..because of their potential applications. These novel materials, prepared either by soft- or hard-templating syntheses, become more and more important in many fields of science and technology such as adsorption, catalysis, separations, environmental processes, nanotechnology and biotechnology. According to IUPAC definition inorganic solids that contain pores with diameter in the size range of 2-50 nm are considered mesoporous materials, They also possess extremely high surface areas (>700 m2 g−1) and narrow pore size distributions. This article review shows the current state of art and outlines the recent patents in mesoporous materials research in three general areas: synthesis, various mechanisms involved for porous structure formation and applications of mesoporous materials based on silica and alumina.
https://ejchem.journals.ekb.eg/article_942_d1f500b64828dc2075a47e7f7fabb8c4.pdf
2016-04-30
163
194
10.21608/ejchem.2016.942
Mesoporous
silica
Alumina
SBA-n
Synthesis mechanism and Application
Heba
Gobara
1
Egyptian Petroleum Research Institute,
AUTHOR
ORIGINAL_ARTICLE
Effect of Some Superplasticizers on the Physico-chemical Properties of the Hardened Cement Pastes
IN THIS work the effect of prepared melamine formaldehyde sulfanilate (MFS) and cyclohexanone formaldehyde sulfonate (CFS) on the physico-chemical properties of the hardened OPC pastes was investigated. The investigation included the determination of the chemically combined water and free lime contents as well as the compressive strength of the hardened admixed cement pastes at different time intervals. Besides, the rheological behavior of the fresh cement pastes was studied. The phase composition of the formed hydration products was identified by using X-ray diffraction analysis. The results showed that as the dosage of admixtures increases, the water of consistency decreases; this leads to a decrease in the initial porosity of the cement pastes, and consequently the compressive strength values increase. Also as the admixture dosage increases, the extent of adsoption on the surface of cement particles increases. This leads to an increase of the negative charge on the cement particles with strong repulsion between them and a consequent enhancement of the rheological properties of cement pastes. The results of X-ray diffraction analysis indicated that the main hydration products formed are the nearly amorphous calcium silicate hydrates (mainly as CSH-I and CSH-II), calcium sulphoaluminate hydrates (ettrringite and monosulphate hydrates) and portlandite (CH).
https://ejchem.journals.ekb.eg/article_1367_d31344bfff0b1bea9aaedc29323a5c87.pdf
2016-04-30
195
208
10.21608/ejchem.2016.1367
Ordinary Portland Cement
Superplasticizers
Free lime
Combined water
Compressive strength and Minislump
ORIGINAL_ARTICLE
Highly Efficient Chelating Polymers Based on Plastic Waste for Removal of Toxic Heavy Metal Pollutants
NEW efficient chelating polymers CPs based on waste …….poly(methylmethacrylate) (PMMA) functionalized by itaconic acid moieties in absence and presence of montmorillonite clay MMT have been prepared by simple solution polymerization technique. The obtained CPs have been characterized using various techniques such as Fourier-Infra-red (FT-IR), scanning electron microscope (SEM), differential scanning calorimetric (DSC) and thermo gravimetrical analysis (TGA). The prepared CPs has been used as potential adsorbents for removal of different toxic metal ions from their aqueous solutions. The CP containing MMT clay showed higher sorption capacity. The adsorption performance of the prepared CPs has been found to match well with Langmuir adsorption isotherms. The maximum sorption capacity for Cu +2 ions was found to be 200.7 mg/g at natural pH 5.8 and was highly enhanced to reach 478.6 mg/g at higher pH values. The correlation coefficient values showed that the sorption of Cu+2 ions by CP with and without clay fit well pseudo-second order models. The highest sorption affinity of the prepared CPs towards different metal ions was in the order Co ˃Ni ˃Pb ˃ Cu˃ Cd˃Cr and Pb˃Cu ˃Cd ˃ Ni ˃Co ˃ Cr for CP without and with clay respectively.
https://ejchem.journals.ekb.eg/article_944_ffcbdbbdd01a80e1c6db01c0d6bc0b28.pdf
2016-04-30
209
227
10.21608/ejchem.2016.944
Chelating polymers
Copper ion uptake
Sorption Kinetics
and Sorption affinity
ORIGINAL_ARTICLE
Drinking Water Issue in North-West Sinai: The Problem and Solution in a Case Study
DRINKING water has received considerable attention recently. However, misuse and mismanagement have resulted in a rapid and widespread decline in source-water quality and supply.Drinking water issuein Sinai is the subject of the present study. The selected area is El-TaqaddumVillage and the surrounding region in North-West Sinai. Different samples of the potable water from the drinking water treatment plant were taken during this study period.Physical and chemical characteristics of the water investigation indicated that pH value ranged from 6.8 to 8.4. Temperatures varied from 17o to 35o. Turbidity ranged from 0.30 to 0.78 as NTU. The level of metals in the studied water can be arranged according to the following decreasing order:- sodium > potassium > aluminum > iron > manganese in the magnitude of :- 150 : 35 : 4 : 2 : 1 respectively. Comparatively high values of Al, Fe and Mn indicated the input of such metals in the raw canal water. It was, therefore, recommended to enhance the settling process of raw canal water before treatment. Storing drinking water for more than two days causes the disappearance of chlorine down to zero. It is strongly recommended that the drinking water of this village should be freshly supplied. This should be associated with a supply of fresh water through the Canal. A continuous follow up of the physical, chemical and biological examination of this drinking water should be carried out precisely. The present investigation showed that the most possible solution is to maintain an initial Cl2 concentration at 2 mg/l and the storing period should not exceed 2 days. To make this clear, residual chlorine in all drinking water supply should be within the permissible limits for safety of the residents. Otherwise, outbreak of epidemic diseases could be at high risk for these poor residents. A continuous flow of the water sources should be supplied to protect the residents of this area with safe treated drinking water.
https://ejchem.journals.ekb.eg/article_945_f22ef10f69c6ffd1c298ebb490c63f5a.pdf
2016-04-30
229
240
10.21608/ejchem.2016.945
ORIGINAL_ARTICLE
Fenton Oxidation Process of Refractory Organics in Gas Processing Wastewater
IN THE CURRENT research, treatment of gas-associated wastewater (3,100 m3/d) from a gas production company located at Alexandria was carried out. The produced wastewater was found to be contaminated with high organic and inorganic pollutants, characterized by high COD (chemical oxygen demand) 55000 mg/L, low BOD (biochemical oxygen demand) 9500 mg/, TSS (total suspended solids) 385 mg/L and total phenols of 0.8 mg/L. The BOD/COD ratio of 0.17 proves that wastewater has hazardous organics that are hardly biodegradable. Due to the low TSS concentration, conventional coagulation precipitation method is not considered adequate. A Fenton reagent [Fe2+/ H2O2] is proposed for degradation of existing soluble organics in the wastewater. Optimum operating conditions were: H2O2 in concentration of 1.6 M/L (one Stoichiometry with COD), 80 mM/L of Fe2+ ions, at pH around 3 and optimal time of 30 minutes. A corresponding residual concentration of COD and BOD were 11000 and 4000 mg/L and a complete removal of phenols. Results concluded that, Fenton reagent was found suitable to improve the biodegradability of the raw gas processingwastewater, BOD/COD increased from 0.17 to 0.36 and a complete removal of phenols has been achieved, making it feasible to be treated biologically in effective manner.
https://ejchem.journals.ekb.eg/article_957_23c622c1612f0d025867a6ec4d6cbdb2.pdf
2016-04-30
241
252
10.21608/ejchem.2016.957
Gas
Dehydration
Wastewater
Refractory
Organics
Removal and Fenton
ORIGINAL_ARTICLE
Fire Retardant Carton by Adding Modified Leather Waste
ONE of the greatest considerable problems of the leather industry is waste generation. About 30% of leather substance processed in tanneries is rejected, mainly after shaving process, in the form of protein waste containing about 10–15% chromium (III). This waste is generally deposited and burned causing hazards to all environment; man, plant and animal. In this work; this waste will be grinded to nanosize, treated with flame retardants then added as filler during the formation of carton sheets. The prepared carton sheets were evaluated using scanning electron microscope (SEM) and thermal gravimetric analysis (TGA). Furthermore, the physical properties as basis weight, sheet thickness, airermeability, density of paper sheet were evaluated. The optical properties of the prepared carton sheets were examined. In addition, the mechanical properties (breaking length, tear factor and burst factor) of the prepared carton sheet were assessed. Moreover, the carton sheets were examined as fire retardants materials. Therefore, these carton sheets can be used as materials for packaging applications.
https://ejchem.journals.ekb.eg/article_971_8ebb868956f5e63ca0c02cd911444be3.pdf
2016-04-30
253
268
10.21608/ejchem.2016.971
flame retardant
Unbleached rice straw
Carton sheet
packaging
SEM and TGA