Lead concentrations in sediments and mollusc gastropod from Vridi Canal, Côte d’Ivoire

Lead (Pb) is one of the most frequent and toxic contaminant in the environment. It can be bioaccumulated by marine organisms through contaminated sediments as well as their food chains. The current study aimed at investigating Pb occurrence in the sediments and gastropod P. haemastostoma from Vridi Canal. Sediment samples were taken using a Van Veen steel grab of 0.02 m2 area, sealed in plastic bags and transported to the laboratory at 4 °C. Gastropod P. haemastostoma species were collected manually using gloves, and then placed in polyethylene plastic bags. The different concentrations were determined using atomic absorption spectrometer Varian AA 20. The results showed seasonal variability of Pb concentrations in sediments and P. haemastostoma. In the both matrices, Pb exhibited the same trend in the distribution between the seasons. This study also mentioned that sediments were highly  contaminated by Pb (54.27-134.71 mg/kg). Vridi Canal was found to be one of the most contaminated seaport area. Pb levels  (49.55-104.19 mg/kg) in P. haemastostoma exceeding the maximum permitted levels according to the United Nations Food and Agriculture Organization (FAO). This research demonstrated that sediments having lower ecological risk may be resulting in lower tissue Pb of P. haemastostoma. Keywords: Metal Pb, sediment, P. haemastostoma, seasonal variatio

Use of plantain peel adsorbents for the reduction of carbon monoxide from biogas for use as chick heating energy in an egg production industry

This research is a case study for the search for an alternative energy to natural gas for heating the chicks of the Brin Foundation located in Yaokokro (Ivory Coast). Specifically, this study aims to reduce carbon monoxide in biogas using biochar and activated carbons prepared from plantain peels. The challenge is to use the purified biogas as an alternative energy source for heating the chicks. Three adsorbents from plantain peel were produced and characterised: 1-Biochar (BC), 2- Potassium hydroxide activated carbon (AC-K) and 3-iron oxide functionalized activated carbon (AC-Fe). Subsequently, their adsorption capacity on carbon monoxide was evaluated. The values obtained for carbonisation yield, moisture and ash content show that the raw material used is suitable for the production of activated carbon biochar. In addition, the surface morphology allows the observation of asperities on the surface of the adsorbents which can be either macropores, mesopores or micropores. The adsorption curves showed that AC-Fe has the longest saturation time of 615 minutes compared to 191 minutes and 188 minutes for BC and AC-K respectively. Furthermore, BC, AC-K and AC-Fe have absorption capacities of 0.77, 0.84 and 3.79 mgCO/g respectively. AC-Fe has a 4.9 times higher adsorption capacity than BC and 4.5 times higher than AC-K. The same case is observed for the percentage of CO removal: 6.9%, 59.83% and 79.19% for BC, AC-K and AC-Fe respectively. According to the efficiency of the adsorbents, they can be classified in the following order: BC < AC-K < AC-Fe. Thus, among the adsorbents used, AC-Fe has the best adsorption capacity and the longest saturation time