Chitin was synthesized from Nigerian brown shrimps by a chemical process involving demineralization and deproteinisation. Deacetylation of the chitin was conducted to obtain Chitosan. The chitin and chitosan were characterized using FTIR, XRD and SEM. Proximate and elemental analysis were also conducted. The percentage yield of chitin was 8.9%. The degree of deacetylation of chitin was found to be 50.64% which was a low value compared to previous works and can be attributed to the low alkali concentration and heating time. XRD patterns indicated that chitin was more crystalline than the corresponding chitosan. FTIR spectra indicated the presence of functional groups associated with different bands, the intensities and stretching established that the samples are chitin and chitosan. SEM analysis also indicated morphological differences between the chitin and chitosan.

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In order to improve properties of natural fibers as reinforcement, different treatment methods have being adopted by researchers. However, the use of sodium hydroxide (NaOH) for the treatment of baobab pod fiber as reinforcement in low density polyethylene is sparsely reported. Therefore, this study, investigated the effect of 2 wt%, 4 wt% 6 wt%, 8 wt% and 10 wt%  concentration of NaOH on baobab pod fibers as reinforcement for low density polyethylene (LDPE). Two roll mill machine and hydraulic press at a pressure of 10 kN and temperature of 120oC aided the production of the composite. FT-IR was used to analyze the functional groups of the treated and un-treated fibers. The result showed the disappearance of the peak 1550 cm-1 corresponding to lignin after modification. Further, the composites were characterized for the following tensile strength (TS), modulus of elasticity (MOE), elongation at break, impact strength and water absorption. Preliminary studies on the effect of loading of the unmodified baobab fiber in the LDPE matrix showed desirable properties at 10 wt%, where fiber content was in the range of 5 wt% to 30 wt% at interval of 5 wt%. The composite produced from the 8 wt% NaOH modified fiber had the highest tensile strength, MOE, elongation at break. At this modification level, the tensile strength, MOE and elongation at break were about 75.48%, 92.18% and 28% respectively higher than the composite produced from unmodified fiber. Composite produced with 10 wt% NaOH modified fiber exhibited least water absorption of 1.80%, which was 50% lower than unmodified. These showed that the modification of the fiber improved the composite properties. These properties compared favorably with some reported properties for natural fiber reinforced polymer composites. http://dx.doi.org/10.4314/njt.v36i1.12

Chemical and physical comparative effect of wet and dry beneficiation processes for p Chemical and physical comparative effect of wet and dry beneficiation processes for p Chemical and physical comparative effect of wet and dry beneficiation processes for p Chemical and physical comparative effect of wet and dry beneficiation processes for purification of kaolin was urification of kaolin was urification of kaolin was urification of kaolin was studied. studied. studied. studied. X X X X-ray flourescence ray flourescence ray flourescence ray flourescence XRF and particle size analysis of kaolin clay before and after beneficiation were carried XRF and particle size analysis of kaolin clay before and after beneficiation were carried XRF and particle size analysis of kaolin clay before and after beneficiation were carried XRF and particle size analysis of kaolin clay before and after beneficiation were carried out. The Si/Al ratio of the raw kaolin out. The Si/Al ratio of the raw kaolin out. The Si/Al ratio of the raw kaolin out. The Si/Al ratio of the raw kaolin which was 1.90 decreased by 1.6 and 17.9% after the wet and dry which was 1.90 decreased by 1.6 and 17.9% after the wet and dry which was 1.90 decreased by 1.6 and 17.9% after the wet and dry which was 1.90 decreased by 1.6 and 17.9% after the wet and dry beneficiation processes respectively. beneficiation processes respectively. beneficiation processes respectively. beneficiation processes respectively. The clay content of the raw clay which was 48 wt% was improved to 73 wt% The clay content of the raw clay which was 48 wt% was improved to 73 wt% The clay content of the raw clay which was 48 wt% was improved to 73 wt% The clay content of the raw clay which was 48 wt% was improved to 73 wt% after the dry beneficiation while the impurity content was reduced from 52 to 27wt%. after the dry beneficiation while the impurity content was reduced from 52 to 27wt%. after the dry beneficiation while the impurity content was reduced from 52 to 27wt%. after the dry beneficiation while the impurity content was reduced from 52 to 27wt%.

Heavy metals discharge associated with industrial activities constitute serious environmental problems, most especially water pollution. Many materials have been identified for the adsorption of these heavy metals and chitosan, a derivative of natural polymer chitin, has been identified as one of such materials. This study was carried out to investigate the removal of chromium (VI) from chromate solution using chitosan from mussel shell, obtained from Gubi dam in Bauchi Nigeria. Chemical method was used to extract the chitosan from the chitin. The chitosan had degree of deacetylation (DDA) of 60.69% and 60.66% as calculated from elemental analysis and FTIR spectra of chitosan respectively and surface area of 2.77m 2 /g. The chitosan was used for removal of Cr 6+ from dichromate-deionised water solution with initial Cr 6+ concentration of 0.62 mg of Cr 6+ per litre of water and the adsorption isotherm established. Optimum chitosan dosage was found to be 2.5 g at 28 o C with a Cr 6+ removal of 82.3%. The time required for equilibrium to be attained was 80 minutes for batch adsorption study. The Langmuir isotherm was the best fitted isotherm with an R 2 -value of 0.983.