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African star apple seed husks, oil seed and whole seed were used for activated carbon production for the treatment and elimination of suspended and dissolved particles from industrial waste water. The activated carbon was produced using chemical activation method with phosphoric acid (H3PO4) and zinc chloride (ZnCl2) as the activating agents at a carbonization temperature of 500 °C. The morphological interpretations and functional groups of the activated carbon were observed using scanning electron microscopy and Fourier transform infrared spectroscopy respectively. Results obtained from the various pollution indicators showed an appreciably improvement on the quality of the water. The pH, temperature, total suspended solids, total dissolved solids and biological oxygen demand were determined with variation of the contact time of the activated carbons with the industrial wastewater. Seed husks of zinc chloride and Oil seed of phosphoric acid produced an activated carbon with the highest adsorptive performance for pH, temperature, Total Dissolved solids (TDS), Total suspended solids (TSS) and Biochemical oxygen demand (BOD) removal at 7.01, 7.14; 25.1 °C, 25.0 °C; 24.20 mg/L, 21.09 mg/L; 17.64 mg/L, 15.4 mg/L and 6.28 mg/L, 4.8 mg/L respectively at 150 min and yield of 75.2% and 54.3%.

The automotive industry is one major sector that consume material such as plastic at the advanced technological level. Hence, automotive plastics are now gaining attention due to the desire for light weight and low CO2 emission from vehicles. It is therefore anticipated that polymer nanocomposites will significantly enhance the performance of current technologies for car industries due to their excellent mechanical, chemical, thermal, electrical and barrier properties and their influence on fire retardancy. Hence, with the use of polymer nanocomposites, the encouraging outcomes in different sectors of automotive industry has resulted to new horizons in terms of advanced polymer nanocomposites for automobile applications. This chapter reviews advance polymer composites for automobile applications. Methods of fabricating polymer nanocomposites and several applications of polymer nanocomposites in automotive industries are discussed.

Innovative membrane processes are considered a very important segment of controllable separation processes, such as water treatment, gas separation and organic purification. One of the challenges in membrane technology is the challenge of selecting and fabricating membrane material for excellent selectivity and good permeability for selected particle sizes. The utmost operational challenge perturbing the performance of membrane technology is membrane fouling which occur as a result of insoluble materials covering the membrane surface, leading to a reduction in water quality. Other factors perturbing the performance of membrane technology are energy usage and greenhouse emission. Furthermore, the necessity to react to climate change is another major challenge for membrane technology. An excellent membrane should have high stiffness in order to withstand high pressures applied, large surface area and micro- or nanopore structures for excellent selectivity and good permeability for selected particle sizes. The transport of ions and fluid at molecular level, controlled at the nanometer-scale using membranes provide substantial capacity for high selectivity and high fluxes. The potential applications of nanoporous membranes are strongly subjected to the chemical and physical properties of a membrane material. The effective pores size, porosity, uniformity, thickness, surface chemistry and morphology also have influence on membrane separation performance. We reviewed the fabrication and potential applications of nanoporous membranes for separation processes, operational challenge, energy usage, greenhouse emission and effect of climate change. Thus, the major points, include: (1) fabrication methods of nanoporous membranes for excellent selectivity and good permeability for selected particle sizes, (2) Theoretical modeling and simulations of nanoporous membranes, (3) potential applications of nanoporous membranes, (4) the recent discovery of novel nanoporous membrane structures aimed at overcoming the challenge of fouling, (5) the challenge of energy usage, (6) addressing climate change as a contributing factor to the challenges of water treatment industry and membrane technology.

This study explores the kinetic and equilibrium performance of eggshell as an adsorbent for hexavalent chromium and cadmium ion removal from wastewater. The experimental removal of the two metal ions was performed batch-wise and the influence of variables like initial metal loading, pH, contact time, and adsorbent dose. Fourier-transform infrared spectroscopy spectra reveals that chromium and cadmium ion interact with carbonyl, carboxylic, hydroxyl functional groups in eggshell. The best pH is 6, and the adsorption capacity improves with increasing initial concentration of adsorbate, pH, contact time and adsorbent dosage for chromium and cadmium ion. Pseudo-second-order kinetics is the most suitable model for the removal of chromium and cadmium ion, while the equilibrium agrees with Freundlich isotherms. These outcomes reveal that eggshell is a promising cheap adsorbent for adsorption of toxic heavy metals like chromium and cadmium ion from aqueous solution.

The inhibitive behaviour of aloe vera as an eco-friendly inhibitor was studied in the corrosion of mild and stainless steel in 0.5 M H2SO4 medium. The varied aloe vera inhibitor concentrations were studied using weight loss (gravimetric) and linear polarization methods. The methods showed that the inhibition efficiency increased with an increase in the concentration of the inhibitor (up to 10 vol/vol%) for both the mild and stainless steels. Stainless steel was found to exhibit a lower corrosion rate compared to mild steel. The results showed that Langmuir adsorption isotherm was obeyed by the inhibition of mild and stainless steel using aloe vera in 0.5 M H2SO4 with the values of the regression coefficients near unity. The negative values of ∆Gads show the spontaneous adsorption of inhibitor on the mild and stainless steel surfaces and a physisorption adsorption mechanism of the aloe vera inhibitor since the values of ∆Gads obtained are more than − 20 kJ/mol, that is, aloe vera is an efficient corrosion inhibitor with mixed-type inhibition property.

The biosorption process of Zn (II) ions in industrial wastewater was investigated using derived composite biosorbents from walnut and snail shells. Composite adsorbents were produced by activating walnut shell carbon (WSC) with phosphoric acid to obtain acid-treated walnut shell carbon (AWSC) and WSC and AWSC were independently impregnated on chitosan to produce walnut shell carbon impregnated on chitosan (WSCC) and acid-treated walnut shell carbon impregnated on chitosan (AWSCC) respectively. The removal efficiencies of Zn (II) ions from synthetic wastewater using the prepared adsorbents were determined. The effects of operational parameters on Zn (II) ions adsorption were investigated. The adsorption data of Zn (II) ions were analysed using Langmuir, Freundlich and Temkin isotherms. The Langmuir isotherm fitted the adsorption data excellently for the derived composite biosorbents, giving an indication of monolayer coverage on the derived composite biosorbents and the determination coefficients were close to unity. Also, the maximum adsorption capacities of 3.1104, 3.8052, 16.4474 and 17.6991 mg/g were obtained for WSC, AWSC, WSCC and AWSCC at pH=5, 1 g of adsorbent dosage, Zn (II) ions initial concentration of 30 mg/L, contact time of 2 h, agitation speed of 150 rpm, particle size of 60 BSS and temperature of 30°C. The kinetic modelling of Zn (II) ions adsorption showed that pseudo second-order kinetic model gave the best fit amongst the investigated kinetic models. The adsorption of Zn (II) ions on the prepared adsorbents was film-diffusion controlled. The experimental results of this study showed that acid-treated walnut shell carbon impregnated on chitosan has the potential to be applied as alternative efficient low-cost biosorbent in the remediation of heavy metal contamination in wastewater. The thermodynamic parameters indicated that the adsorption of Zn (II) ions on the derived composite biosorbents was exothermic, endogonic, favourable, non-spontaneous with changes in enthalpy (, negative), entropy [, nearly zero (though negative)], and Gibbs free energy (, positive), for all the prepared adsorbents. Key words: Adsorption, biosorbents, chitosan, isotherm, kinetic models, film diffusion.

A one-dimensional adiabatic mathematical model was developed for the riser reactor of an industrial residue fluid catalytic cracking unit (RFCCU). A seven-lump kinetic model was presented for the catalytic cracking of vacuum residue, taking cognisance of diffusion resistance, which is a departure from the general norm in the literature. Also, heat transfer resistance between the fluid and solid phases was incorporated into the energy balances for instantaneous and one-dimensional vaporization of feedstock. The developed model was a set of twelve coupled, highly non-linear and stiff ordinary differential equations, ODEs, which was numerically solved with an implicit MATLAB built-in solver, ode23t, designed deliberately for handling stiff differential equations to circumvent the problem of instability associated with explicit methods. An excellent agreement was achieved between the industrial RFCCU plant data and the simulated results of this study, with average absolute deviation being

Biodiesel was produced from the transesterification of soybean oil using calcium oxide and cow bone (an animal waste bone that contains hydroxyapatite, a calcium phosphate mineral) as heterogeneous catalysts. The soybean oil used was characterized using gas chromatography mass spectrometer (GCMS) and the cow bone catalyst produced was characterized using X-ray diffractometer (XRD) and X-ray fluorescence (XRF) spectrometer. The effects of the variation of methanol/oil mole ratio (9–15), catalyst concentration (10–20 wt/wt%) and reaction temperature (55–65 °C) on biodiesel yield during the transesterification of soybean oil with methanol was investigated. Reaction time of 3 hours and stirring rate of 500 rpm were kept constant. It was observed that the calcination of cow bone catalyst (at 800 °C) enhanced its conversion to apatite [Ca5(PO4)3OH] and increased the yield of biodiesel obtained. Biodiesel yield results revealed an optimum condition of methanol/oil mole ratio of 9, catalyst concentration of 15 wt/wt% and reaction temperature of 55 °C. Also, the results obtained showed that the performance trends of the two catalysts used were similar. And the close values of highest biodiesel yields obtained when the two heterogenous catalysts were used separately (yields of 94.8 and 92.2% using calcium oxide and calcined cow bone catalysts respectively) implies that the use of low-cost and readily available calcined cow bone catalyst is a promising alternative to CaO catalyst.

Corrosion inhibitor has been successfully used for the protection of 3CR12 stainless steel surface against corrosion in 1–2.5 M HCl. The performance of this inhibitor was correlated to the chemical composition and microscopic structures in accordance with the adsorption on the metal surface. Deoxyribonucleic acid (DNA) was extracted from the thymus gland of a calf, a component of the immune system of mammals. The study investigated the use of DNA extracted from calf thymus gland as a protective coat for 3CR12 stainless steel in the presence of a hydrochloric (HCl) medium. The mechanism of the potential inhibitor was understudied at different conditions of temperature and concentration in order to be able to explain the influence of the inhibitor on the metal. The highest CTGDNA inhibition efficiency was attained at 10 °C and at 20 mg/L. The micrographs revealed by scanning electron microscopy show that bio-macromolecules of CTGDNA were adsorbed on stainless steel surfaces. Nonetheless, the best micrograph result was achieved at 10 °C. The study of the Tafel polarization demonstrated that CTGDNA inhibitors at different concentration represented some mixed-type inhibitors. An inhibition mechanism was proposed which was confirmed by X-ray powder diffraction analysis. The results indicated that the corrosion inhibition efficiency increased with increase in HCl concentration.

The absence of public transportation has led to the growth and expansion of paratransit modes. This has increased traffic congestion, traffic crashes and traffic pollution. This research assessed the effect of demographic characteristics on para transiting in Lagos with special focus on the mainland. To achieve the aim of this research, the mainland was divided into two zones based on the geographical location which are the Ikorodu and Ikeja zone. Domiciliary information techniques were used in data collection. This was backed up with an oral interview. Two hundred question (200) questionnaires were administered with 89% return rate. The information captured were demographic characteristics, the volume of trips, frequency of trips, trip types, operations of the paratransit transportation system, travel behaviour of passengers (travel time, travel cost, travel purpose). SPSS version 18 was used for the data analysis. The result of the survey revealed that paratransit modes serve as a feeder connection between neighbourhoods in the study area. Additionally, it provides a feeder connection between major arterial roads (truck A and B roads). Flexibility accounts for 41% of the reason why paratransit mode is preferred by respondents. The bivariate analysis showed a weak negative relationship for the correlation between frequency of trip and age. The outcome of this research will aid transportation planners, policymakers, and transportation experts on the appropriate strategy to adopt for effective mobility as a unimodal approach to providing effective movement may not be foreseeable in the study area.

The contamination of soil originated from evolutional activities such as transportation and spillage, as in the case of Ogoni land in the Niger Delta area of Nigeria, and it is a well-known environmental problem in Nigeria. This study examined the capacity of two indigenous bacteria, Pseudomonas aeruginosa, and Bacillus subtilis to remediate the hydrocarbon contaminated soil. The focus of the work was to isolate, identify, and determine the extent of bioremediation achieved in the soil contaminated with crude oil in Ogoni land, which was used as a case study for the slurry-phase bioremediation process. These organisms earlier mentioned were identified based on their morphological and biochemical characteristics. The bacteria species were considered separately and in combination in a Laboratory-scale slurry-phase in a 14-day treatment period using 30 g of soil for each case. The performance of each batch bioreactor was compared to the sterile control. The slurry phase bio-reactor, RA, treated with Pseudomonas sp., had an actual degradation of 31%, the slurry phase bio-reactor, RB, treated with Bacillus sp., had a real degradation of 35%. The slurry phase bio-reactor Rc, which contain both microorganisms had an actual degradation of 36%, the slurry phase bio-reactor RD had a real degradation of 0%. The results obtained confirm that the isolated bacterial from the soil can effectively utilize contaminating crude oil as a source of carbon and energy. The decrease of hydrocarbon in the sterile control was used as a basis for comparison of the petroleum hydrocarbons lost through the extraction process as microbiological activity was not possible. Results from the study have shown that P. aeruginosa and B. subtilis strains were effective for the slurry-phase bioremediation of hydrocarbon contaminated soil.

The Inhibition efficiency of Rosemary oil (Rosmarinus officinalis) for corrosion control of high carbon steel was done in citric acid medium by weight loss method. The Rosmarinus officinalis was administered in the proportion of 0%, 0.50%, 1.00%, 1.50%, 2.00% and 2.50% concentration. This study unveiled that the inhibition efficiency performed excellently with maximum percentage of 88.3% at room temperature in 0.5M citric acid solution. This has shown the effectiveness of Rosmarinus officinalis inhibitor in corrosion analysis of high carbon steel.

The hydrogen sulfide (H S) emission and oxygen (O2) level was measured within four bakeries in Ota, Ogun State. This was done to know the effect of H2S on the people working in bakeries and those walking into bakeries for business purposes. The data obtained was analyzed and the H2S emission level was around the new recommendation for airborne of 1 ppm recommended for 8 hours by ACGIH (American Conference Governmental Industrial Hygenist [1]. The highest mean concentrations of H2S were; bakery 1 (0.4 ppm), bakery 2 (0.73 ppm), bakery 3 (1.0ppm), H2S emission was not detected by the gas analyzer in bakery 4. O2 level (20.8ppm) remained constant all through the study, which is the expected ambient O2 value, this is because of the cross ventilation within the bakeries. Though literatures have shown that ovens emit some harmful gases like CO, NOx, VOC and H2S, the concentrations of these gases can be reduced if there is cross ventilation within the bakery and exhaust stacks positioned high enough towards the roof, out of the building. The stack effect happens, when warm air moves or flow upwards in the building. The warm air rises because it is lighter than cold air, when it rises, it escapes out of the upper levels of the building through ventilation openings, windows or leakages. The rising warm air reduces the pressure at the base of the building, forcing cold air to infiltrate through either open doors, windows, or other openings and leakage in lower levels of the building. The H2S emission level was higher during the heating periods than the baking periods in all the bakeries considered due to the combustion process taking place during heating. The electrically fired ovens gave lower H2S concentrations than the wood fired ovens. To ensure safety for workers and consumers in Bakeries, regular inspection of bakeries should become a priority for the various agencies involved.

This paper assessed the environmental impact of a telecommunication base transceiver stations (BTS) located at Cardoso Close, Apapa, Lagos State, Nigeria with the coordinates 6°4392’N, 3°3126’E. The ambient air quality parameters: SO2, NO, CO, CH4 and total suspended particulates (TSP) were measured using the ITX Emission Analyzer at four sampling points within the base station. The concentrations of SO2, NO, CO and TSP atthe base station ranged between 0.3-0.5 ppm, 1.9-2.2 ppm, 5.5-7.5 ppm, 101-110 µg/m3 respectively for 24-hour averaging period. CH4 was not detected at any of the sampling points. A digital Realistic Sound Level Meter was used in measuring the noise level. The measured average noise levels in all the four sampling points at the BTS studied ranged between 83.1-88.7 dB (A). Samples of water were collected from boreholes around the base station and were subjected tophysico-chemical examinations using the ‘standard methods for water and waste water’ 14th edition prepared by American Public Health Association (APHA). The analyses of the water samples showed that all the parameters are within limits. To measure the electromagnetic radiation emitted from the station during the field study, the SPECTRAN HF-4049 RF, an in-situ dosimeter for radio frequency measurement was used. The results obtained showed that, the measured averageradiation levels in all the four sampling points within the BTS studied ranged between 0.051-0.054 µW/m2. All the measured parameters are within safety margins apart from SO2 and NO. SO2 was not traceable to the BTS while NO was only partly connected with the fossil-fuelled electricity generating sets. The parameters of the physico-chemical analysis of the borehole water were significantly below limits.

Demulsification is a method used to reduce or disrupt the water - crude oil emulsion system without uttering the initial composition of the crude oil. This process is done by the introduction of chemicals called demulsifiers, which break the emulsion into aqueous and organic phases. In this study, the demulsifier formulated was the base-catalyzed phenol-formaldehyde resin known as the resoles, with the ratios of phenol to formaldehyde, varied between 1.0:1.2 and 1.0:2.0. The different samples of resoles where then ethoxylated to make them more hydrophilic using different weights (10, 15 & 20 g) of polyethylene glycol (PEG). Screening of the ethoxylated demulsifiers was done using the established bottle test procedure, at 70 °C, the concentration of 50 ppm, and 20 minutes of residence or separation time, in order to select the most effective demulsifier, based on the amount of water removed from the emulsion. The best chemical-demulsifier produced was the ethoxylated resole, which was then blended with xylene at varying percentages (0, 20, 40, 50, and 80 % weight/weight) and was further screened, using the bottle test method. From the analysis, it was obtained that the most effective ethoxylate-xylene demulsifier blend was sample DR3, and made of formaldehyde to phenol ratio of 1.8:1, 20 g of PEG 400 blended with 20 % xylene. The demulsifier gave a water separation efficiency of 85.7 %, compared with the commercial demulsifier, which yielded 72.7 %. The result indicates the practical significance of solvent modified demulsifiers for separating crude oil emulsions in the petroleum industries.

Hybrid Boundary Value Method (HyBVM) is a new scheme, which is based on Linear Multistep Method (LMM). The HyBVM is the hybrid version of the Boundary Value Methods (BVMs) which are methods derived to overcome the limitations of the LMMs. This new scheme shares the same characteristic with the Runge Kutta method as data are utilized at off-step points. In this work, we apply this method to two second order Boundary Value Problems (BVPs) with mixed boundary conditions and the results are efficient when compared to other BVMs in literature.

The research work investigated the production of adhesive from cassava starch. Cassava tubers were processed into starch-based adhesives, using two different gelatinization enhancers (that is HCl and NaOH) which were introduced separately. The adhesives were produced by considering two varied process parameters, namely percentage weight of borax in starch solution (8 – 20%) and reaction temperature (65 – 85°C). Comparative analysis of the adhesive obtained (using HCl and NaOH as gelatinization enhancers) include the determination of its bond strength, viscosity, drying time, pH and density. As the borax weight percent increases up to 14 % and reaction temperature reduces (using NaOH) the drying time increases, while the drying time reduces as both the borax weight percent and temperature reduce (using HCl). The results of the adhesive physical properties fall within the standard range for each of the properties and this implied that the adhesive produced was of high quality.

Water borne diseases have continued to linger and has remained a major challenge facing most developing nations today. This has been caused mainly by lack of access to clean water. The rapid industrialization has led to the discharge of effluents loaded with pollutants into our water bodies that have greatly affected humans, aquatic life and the environment. This work looks into the possibility of improving the quality water through the elimination of (i) inherent contaminants in water using filters made from cheap locally available red clay and biomass (300 microns sawdust) materials and (ii) chemical treatment of industrial and domestic effluents which in itself is a source of environmental pollution. The sawdust-clay materials were first thoroughly dry mixed in four different weight ratios, 6/80 (sample A), 5/80 (sample B) 4/80 (sample C) and 2/80 (sample D) before water was then added gradually and mixed until the clay clumped together completely, softened and workable. It was then wedged by pressing firmly in order to remove bubbles from the inside of the clay and molded into cup--like shape. It was first sun dried then oven dried at 110 °C and then fired in a Muffle furnace at 850 °C to burnout the sawdust biomass and thus create fine pores within the clay matrix. Performance of the sawdust-clay filters for the purification of waste water obtained from two different sources, industrial and kitchen effluents, was investigated. Results obtained from the study showed that the four filters (A, B, C and D) proved to be moderately effective for the treatment of the two effluents. All the filters reduced the total dissolved solids (TDS) to 120 and 110 mg/L of the industrial and kitchen waste water respectively, to acceptable levels which is less than 500mg/L, set by the World Health Organization (WHO). Conductivity values obtained after the treatment of the water samples were lower than the 1000 µs/cm limit set by WHO. And with the exception of filter D, others greatly reduced the turbidity of water samples as values less than 5 NTU as set by WHO were obtained. The pH values or acidity reduced for the industrial waste water from 4.5 to 7.02 and for kitchen waste water from 5.1 to 7.02 which met the specification set by WHO. Some of the heavy metals detected in the water samples were effectively reduced to acceptable levels. The filtration rates were 140, 100, 50 and 20 ml/min for filters B, A, C and D respectively. The rates rapidly reduced to about 2.7, 1.7, 1.0 and 0.7 ml/min for A, B, C and D respectively after 30 minutes of filtration. This implies that the filters were effective and should thus be developed for industrial and domestic waste water treatment applications.

The de-emulsification of a Nigerian crude oil emulsion has been investigated using locally formulated base and acid catalyzed phenol formaldehyde resins with varied formaldehyde to phenol molar ratios. The bottle test method was used for the screening process and the best de-emulsifier was chosen based on the largest volume of water removed from the crude oil emulsion. The screening process was done at temperatures of 50 and 70°C and de-emulsifier concentrations of 20 and 50 part per million (ppm), respectively. A factorial design was done to determine the best combination of de-emulsification conditions for optimal performance. The results were optimized and analyzed using software called Minitab 16 utilizing pareto chart, normal effects, main effects and interactions plots. From the analysis, it was found that the optimum set of conditions for best performance of the resole de-emulsifier were 50 ppm, 70°C and 1.8:1 concentration, screening temperature and formaldehyde to phenol molar ratio, respectively. While for novolak de-emulsifiers, they were 50 ppm, 70°C and 0.1:1. Increasing temperature and concentrations were found to enhance de-emulsification performance with all the resole and novolak de-emulsifiers.