Production of activated carbon from date palm pits and its use in industrial wastewater treatment

The present study investigates, for the first time, the production of granular activated carbon (GAC) from date palm pits, a waste material. Reported data indicates.that the t. yearly production of dates in the Kingdom of Saudi Arabia (KSA) is more than 800 ktonnes of which a significant portion is de-stoned prior to sale. Hence the use of date palm pits for the production of GAC would confer two benefits, Le., reduction in waste disposal costs and concerns and production of a very useful material from this waste, Le., GAC, which at the present is imported in the KSA for several industrial applications.Considering these facts, date palm pits from a local source were used for the production of GAC. Several GAC production variables were investigated in detail, to study their effect on the BET specific surface area (SSABET), porosity, and the pore size distribution of the produced material. Variables studied included sample predrying, time of carbonization, time of activation, strength of the activating agent (i.e., phosphoric acid), acid impregnation ratio, pH, and temperature. Nitrogen adsorption isotherm data was used for the determination of respective SSABET, and porosity values.The optimum conditions that produced the best activated carbon were, H3P04 concentration equal to 70%, acid to pits ratio of 1.6:1, and carbonization temperature of 500°C. Additionally, a maximum yield of 24% was noted for the best GAC sample which showed the following characteristics 590 kg m-3 bulk density, 0.5% ash content, 1100 mg g-1 iodine number, and 1319 m2 g-1 SSABET. Furthermore, this GAC sample showed substantial capability to adsorb phenol and 2-Methylphenol (o-cresol) from the aqueous phase. The respective adsorption data fitted well to the Freundlich adsorption isotherm. Several continuous column studies (using operational variables including flowrate, initial pollutant concentration, pH, temperature and dissolved oxygen) were also conducted to find the suitability of the produced optimum GAC sample for the removal of phenol and 2-Methylphenol from the aqueous phase. For example, the adsorption of both phenol and 2-Methylphenol was influenced both by the flowrate and the initial pollutant concentration. Also, the breakthrough time decreased when the flowrate and the initial concentration values were increased, probably due to insufficient pollutant residence time. The respective optimum activated carbon was also successfully used for the reduction of total organic carbon from an industrial wastewater sample.Furthermore, to minimize waste disposal cost and concerns related to the exhausted GAC, an attempt was also made to regenerate the used GAC sample from the present work using chemical and electrochemical desorption methodologies. The electrochemical desorption method, which so far has been scantly investigated in the literature, was noted to successfully regenerate the used GAC sample, using a current density value of 50 rnA cm-2. Factorial experimental design and optimization of parameters for the production of GAC from date pits, using Response Surface Methodology (RSM), was also completed. The respective results were acid to pits ratio of 1.5:1, carbonization temperature of430°C, and H3P04 concentration of 55%. In summary, a high efficiency GAC sample was successfully produced from an otherwise waste material i.e., the palm date pits. The produced GAC was also noted to be very efficient for the removal of organic pollutants from the aqueous phase. It is suggested that the use of activated carbon produced from date pits would be economical, since date pits are a waste product and available in large quantity in the Kingdom of Saudi Arabia, and phosphoric acid is manufactured from local resources in the Kingdom

Myelodysplasia in a psoriasis patient receiving etanercept : Cause or coincidence?

Peer reviewedFinal Accepted Versio

Reallocating charging loads of electric vehicles in distribution networks

In this paper, the charging loads of electric vehicles were controlled to avoid their impact on distribution networks. A centralized control algorithm was developed using unbalanced optimal power flow calculations with a time resolution of one minute. The charging loads were optimally reallocated using a central controller based on non-linear programming. Electric vehicles were recharged using the proposed control algorithm considering the network constraints of voltage magnitudes, voltage unbalances, and limitations of the network components (transformers and cables). Simulation results showed that network components at the medium voltage level can tolerate high uptakes of uncontrolled recharged electric vehicles. However, at the low voltage level, network components exceeded their limits with these high uptakes of uncontrolled charging loads. Using the proposed centralized control algorithm, these high uptakes of electric vehicles were accommodated in the network under study without the need of upgrading the network components

Model of Transmission Rate Allocation WiMAX with Taking Into Account the Defined Priorities

The results of development a mathematical model for transmission rate allocation downlink technology WiMAX are presented. The novelty of the proposed model is possibility to prevent a limit transmission rate allocated to the service flows of the user stations in the downlink by using the WiMAX technology linear or linearquadratic objective function. Using the mathematical model is directed to allocation between subscriber stations of a time-frequency resource of the downlink, which in turn improves the conditions in the electromagnetic frequency range used. The influence of the priority request rate used in the model is the nature of the possible failure

4D Printing of origami structures for minimally invasive surgeries using functional scaffold

Origami structures have attracted attention in biomedical applications due to their ability to develop surgical tools that can be expanded from a minimal volume to a larger and functional device. On the other hand, four-dimensional (4D) printing is an emerging technology, which involves 3D printing of smart materials that can respond to external stimuli such as heat. This short communication introduces the proof of concept of merging origami and 4D printing technologies to develop minimally invasive delivery of functional biomedical scaffolds with high shape recovery. The shape-memory effect (SME) of the PLA filament and the origami designs were also assessed in terms of deformability and recovery rate. The results showed that herringbone tessellation origami structure combined with internal natural cancellous bone core satisfies the design requirement of foldable scaffolds. The substantial and consistent SME of the 4D printed herringbone tessellation origami, which exhibited 96% recovery compared to 61% for PLA filament, was the most significant discovery of this paper. The experiments demonstrated how the use of 4D printing in situ with origami structures could achieve reliable and repeatable results, therefore conclusively proving how 4D printing of origami structures can be applied to biomedical scaffolds

Assessment of Knowledge Regarding Osteoporosis Among Female Medical Students at King Faisal University, Saudi Arabia

Introduction: Osteoporosis is a worldwide public health problem that affects both male and females. It is a silent progressive disorder that affects the skeletal system and leads to diminished bone density and fracture. Therefore, awareness, attitude, and practices of people about osteoporosis contribute significantly to primary prevention and early detection of disease. Objective: the present study conducted to assess the knowledge of the female medical students at King Faisal University about osteoporosis in Saudi Arabia. Study design: A cross-sectional study conducted at the medical college of King Faisal University at Al-Ahsa region, Saudi Arabia. The study included all female medical students at King Faisal University, through an online self-administered questionnaire using the Osteoporosis Knowledge Assessment Tool (OKAT) questionnaire. Results: The total number of participants was 176 female medical students, with 58.7% response rate. The age of participants ranged between 17 and 27 years, with a mean and standard deviation of 21.46±1.54 years. The participant's knowledge score about osteoporosis was as follow: 65.1% had satisfactory knowledge, 32.2% had poor knowledge, and only 2.3% of the participant had good knowledge. Conclusion: Most of the participants had a satisfactory knowledge score on osteoporosis. However, there was a significant gap in knowledge regarding the risk factors such as high salt intake. The good knowledge score was significantly low in the present study compared to worldwide. Therefore, an educational effort is needed to improve knowledge and the quality and reliability of information about osteoporosis targeted undergraduates and young females in Saudi Arabia

Design a Gray Water Treatment System for a Virtual Building Working by Solar Energy

This work has showed that gray water can be used in irrigation with great success. It includes the explanation of how water recycling will save water for irrigation and agriculture use, reduce the costs of constructing purification plants, and add natural filters to the environment. It also aspires to invite companies to reduce the proportion of phosphate and other harmful substances in the composition of soap. In addition, it is possible to reduce the amount of suspended solids in a gray water by installing filters on the washing machines themselves, so that the volume of problems in the plankton is reduced at the refineries. It was found that the decrease in the consumption and rationalization of electric energy was observed for other purposes using the solar cell system, which is considered as a source of power supply system