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There is growing concern to determine an alternative adsorbent for remediating landfill leachate effluent with minimal environmental impact and operational cost. In this work, four low cost sustainable biocomposite materials such as limestone, peat, activated carbon and zeolite were employed as an adsorbent media in an adsorption batch study for the removal of ammoniacal nitrogen from landfill leachate. Isotherm adsorption models of Langmuir and Freundlich were utilized to analyze the adsorption data. The Langmuir isotherm model showed the best fit for experimental data with a maximum monolayer adsorption capacity of 26.18 mg/g which is indicated that the ammoniacal nitrogen adsorption took placed on the surface of biocomposite with monolayer formation of the adsorbate at a specific homogeneous site. The adsorption isotherm follows Langmuir’s model (R2 = 0.99) and Freundlich’s model (R2 = 0.98)

There is growing concern to determine an alternative adsorbent for remediating landfill leachate effluent with minimal environmental impact and operational cost. In this work, four low cost sustainable biocomposite materials such as limestone, peat, activated carbon and zeolite were employed as an adsorbent media in an adsorption batch study for the removal of ammoniacal nitrogen from landfill leachate. Isotherm adsorption models of Langmuir and Freundlich were utilized to analyze the adsorption data. The Langmuir isotherm model showed the best fit for experimental data with a maximum monolayer adsorption capacity of 26.18 mg/g which is indicated that the ammoniacal nitrogen adsorption took placed on the surface of biocomposite with monolayer formation of the adsorbate at a specific homogeneous site. The adsorption isotherm follows Langmuir’s model (R2 = 0.99) and Freundlich’s model (R2 = 0.98

Natural material, agricultural waste, and industrial waste are locally accessible resources that are utilized as environment-friendly and inexpensive sorbent. The natural abundance source like green waste mussel shell (GWMS) adsorbent makes them an advantageous basic sorbent material to produce inexpensive water treatment adsorbent. This study addresses the evaluation of GWMS as an efcient sorbent material to minimize the utilization of traditional adsorbents namely activated carbon (AC) and zeolite (ZEO) for removing pollutants from leachate. COD and ammoniacal nitrogen (NH3–N) were identifed as the two problematic parameters in landfll leachate. Batch adsorption experiments were performed with 100 mL of prepared leachate solution in 2.5 g, 7.5 g, and 12.5 g dosages. The leachate solution was shaken in an incubator for 2 h at 200 rpm shaking speed and pH 7. The GWMS dosage at 7.5 g illustrated that the removal percentage of COD is 71% and that of NH3–N is 47%. The adsorption capacity related to the complete monolayer coverage of saturated molecules shows that the maximum adsorption capacity of COD is 47.39 mg g−1 and that of NH3–N is 26.18 mg g−1. Langmuir and Freundlich values are better described by Langmuir than Freundlich based on R2 values for COD > NH3–N where 0.9941>0.9891. The R2 values for COD > NH3–N for the linear plot of the pseudo-second-order were 0.9997>0.9763, respectively.

There was  range of disadvantages in the informal roadside metalwork fabrication apprenticeship practice in north western Nigeria that includes the lack of appropriate technical skills to better serve the society.  The purpose of this research was to identify those technical skills needed for the informal roadside metalwork fabrication apprenticeship practice in Nigeria. To this effect an investigation was carried out through a survey research, using questionnaire instrument and interview as entailed by methodological triangulation. The survey research was conducted using 140 population of master craft persons from sampled workshops in seven states of North West geo-political zone of Nigeria, using a structured questionnaire instrument. Interview of 10 participants was made, who were randomly selected from, industry-based trainers, lecturers and instructors within the seven states in north western Nigeria. The interviews were conducted to ensure a balance result. Open coding was made, followed by Axial coding. Selective coding was lastly made and the results were interpreted as it complemented the descriptive results which entailed the methodological triangulation method. To validate the results obtained from methodological triangulation, eleven Delphi panel of experts were involved. Binary analysis and Kendall’s coefficient of concordance (Kendall’s Wa) were used to measure and determine the consensus of the experts on the technical skills items. Positive results were obtained because the level of consensus between the participants was 0.621. The results also indicated inter-judge reliability. Suggestions were made for the improvement of the sector, as the appropriate and valid technical skills needed were outlined. Keywords: Technical skills, apprenticeship practice, validation, improvement, needs.

Adsorbent from abundant residues of palm oil known as empty fruit bunch (EFB) was prepared to investigate the removal of Chemical Oxygen Demand (COD) from natural rubber wastewater. The EFB was modified using citric acid (CA) to enhance adsorption ability. The adsorption conditions such as adsorbent dose, pH and contact time for the effective removal of COD were optimized. Isotherms were generated to describe the removal of the COD. Results have shown that the optimum reaction conditions for COD adsorption by the EFB were 3 g of adsorbent, pH 7 and 120 min as contact time for the effective removal 76% of COD in natural rubber wastewater. Meanwhile, the adsorption data for COD on the EFB fitted the Langmuir isotherm, suggesting a monolayer adsorption behaviour of the adsorption processes. This study indicated EFB is a promising candidate adsorbent for the removal of COD in wastewater.