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Abstract. The growing concern over the severe impact on the global climate change of the buildup of CO 2 in the atmosphere has resulted in the quest to capture or avoid the release of CO 2 at large point sources into Nigeria environment. The study uses data obtained for various cement plants on design capacity from cement plant production database, Nigeria. The data were analyzed using the "Generic CO 2 Capture Retrofit" spreadsheet developed by SFA Pacific Inc. The results of the analysis obtained from the models shows that the ranges of the costs of CO 2 captured and avoided per tonne CO 2 were $27-47 and $34-60 respectively. With these values on a high side, will help the cement plants to decide whether to adopt the Carbon Credit option or consider Carbon Capture and Sequestration (CCS). The demand for fossil energy in most of the cement plant appears to be one of the most significant issues to tackle if the problem of climate change mitigation in Nigeria has to be given serious attention. In light of the forgoing high costs of CO 2 capture and avoided estimate for the cement plants, we recommend that Nigeria should invest in energy efficient technologies and should utilize less usage of fossil fuels.

The influence of various factors namely pH, absorbent dosage; contact time and initial ion concentration was studied to identify the adsorption capacity of the adsorbent. The optimum pH was obtained at pH =3 for all the adsorbent. Other physiochemical parameters, ranging from the surface area to the scanning electron microscope (SEM) were studied and indicate that the cocos nucifera husk is a good precursor for investigation on activated biomass for hardzadous cyanide wastewater. Adsorption data were modeled using Langmuir, Freundlich, Temkin, Henry and T. D. Yavini et al. J Fundam Appl Sci. 2017, 9(1), 354-377 355Equibrium data were best described by Henry model. Kinetic models were also carried out including pseudo first order with R 2 = 0.969, Pseudo-second order R 2 = 0.998, Intra-particle diffusion R 2 = 0.909, and Elovich Kinetic model with R 2 of 0.814, the kinetic data were best described and seen by Pseudo second order model. It is then proven that the study of the entire adsorbent are most efficient for the removal of cyanide from waste waters and it can be used as low-cost adsorbent for the removal of cyanide ions from wastewater.