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Essentials for Chemical Engineers

Abstract

Studies on the adsorption of Pb(II) on plantain peels biochar (PPB) was conducted. The carbonized and activated, biochar was characterized using Braunauer-Emmett-Teller (BET) surface area and x-ray diffraction crystallography (XRD). BET analysis of the PPB indicated that the pore size (cc/g) and pore surface area (m2/g) was 8.79 and 16.69 respectively. Result of the XRD evaluated through Debye-Scherrer equation, showed a nanostructure with crystallite size of 14.56 nm. Effects of initial metal ion concentration, pH, and contact time were studied in a batch reaction process. Results showed that the adsorption of lead from aqueous solution increased with an increase in pH and initial concentration. Equilibrium modeling studies suggested that the data fitted mainly to the Langmuir isotherm. Adsorption kinetic data tested using various kinetic models fitted the Weber and Morris intraparticle diffusion model implicating pore diffusion as the main rate limiting step. The sorption studies indicated the potential of plantain peel biochar as an effective, efficient and low cost adsorbent for remediating lead (II) ions contaminated environment.

Abstract

Hormonal changes in humans and animals can be attributed to endocrine disrupting chemicals (EDCs). Studies have found that excessive exposure to natural and artificial environmental chemicals and toxins can have adverse effects on the endocrine system and reproductive health. The endocrine system creates and releases hormones that regulate the development of organs and how they function. Any disruption to hormones affects the development and functioning of the reproductive system, the brain and the neurological system. Research and reports on the subject have been published by international experts and organizations including the World Health Organization (WHO), United Nations Environment Programme (UNEP), International Labour Organization (ILO) and Endocrine Society. To fully comprehend the effect of EDCs on humans and wildlife, it is essential to understand epigenetics and its transgenerational effects on hormone development. Here, we extensively explore and review the research on the sources of EDCs, their effects and why exposure to EDCs is of concern, and treatments for EDC exposure.

Abstract

Single cell supercapacitors with electrodes of varying amounts of graphene and carbon black, formed via the electrospinning process with a carbon-based Polyacrylonitrile (PAN), were tested in 1M H2SO4. From the tested samples, the overall data indicates no correlation between impedance and capacitance energy values. However, the breakdown of the various samples showed mixed results of; good correlations between lower impedance resulting in higher and lower capacitance; while other samples showed higher impedance correlating to both higher and lower capacitance. No correlation was observed between the Impedance value and the thickness of the samples. Furthermore, carbon mole content was not a major factor in determining impedance; therefore, structure is not a major contributor to impedance. Whereas, carbon mole content is a major contributor to capacitance energy; Hence, impedance provides an alternative control point to increasing energy ( 2-10X times ), that can be retrofitted to existing systems, or to increase the energy storage beyond current levels by adjusting/controlling impedance in new designs. The data is indicating impedance is not constant and is varying. The mechanism of varying impedance is unclear and requires further research. However, it is thought to mimic the energy level and stability of matter (atoms). Therefore, impedance varies or oscillates accordingly to achieve an impedance level stability, and hence the term “Orbital Impedance Stability”. Thoughts into Impedance being an Energy Field, to be provided in next publication (In-sha’-ALLAH). This research is concluding that our conventional understanding of impedance is limited in scope. New approaches and further research is needed to better understand impedance behavior. A better understanding of impedance is essential to a breakthrough in energy storage devices from capacitors and batteries, to electric generation and distribution of energy, to magnetic levitation, medical drugs and other energy improvements.

Abstract

Hydrotreatment of bio-oil oxygen compounds allows the final product to be effectively used as a liquid transportation fuel from biomass. Deoxygenation is considered to be one of the most promising ways for bio-oil upgrading. In the current work, we describe a novel approach for the deoxygenation of bio-oil model compounds (anisole, guaiacol) using supercritical fluids as both the solvent and hydrogen-donors. We estimated the possibility of the use of complex solvent consisting of non-polar n-hexane with low critical points (Tc = 234.5 ºC, Pc = 3.02 MPa) and propanol-2 used as H-donor. The experiments were performed without catalysts and in the presence of noble and transition metals hydrothermally deposited on the polymeric matrix of hypercrosslinked polystyrene (HPS). The experiments showed that the presence of 20 vol. % of propanol-2 in n-hexane results in the highest (up to 99%) conversion of model compounds. When the process was carried out without a catalyst, phenols were found to be a major product yielding up to 95 %. The use of Pd- and Co-containing catalyst yielded 90 % of aromatic compounds (benzene and toluene) while in the presence of Ru and Ni cyclohexane and methylcyclohexane (up to 98 %) were the main products.