EVALUATION OF PHYSICOCHEMICAL, POLYMERIC AND METAL CONTENTS OF SELECTED TROPICAL TIMBERS IN NIGERIA

SOURCE:

Faculty: Physical Sciences
Department: Pure And Industrial Chemistry

CONTRIBUTORS:

Ezigbo, V.E;
Eboatu, A.N;

ABSTRACT:

The qualitative and quantitative phytochemical analyses of 50 timbers of Nigeria were carried out. The physicchemical properties such as polymeric test, phytochemical test, solubility test, proximate analyses, saponification value, iodine value, acid value and peroxide value and elemental analyses of the wood species were determined. Results showed that the range of experimental values of the chemicals as well as other physical parameters were: moisture content (9.2 – 34.4 %), ash content (0.5 – 34.0 %), specific gravity (0.012 – 0.39), thermal conductivity (182.00 – 105665.00 µohm), charring temperature (60 – 94oC), porosity (0.06 – 0.068), crude fibre (33.78 – 40.74 %), fibre length (1.54 – 1.98 mm), cellulose (0.53 – 93.3 %), hemicelluloses (20.0 – 37.0 %), lignin (5.6 – 79.4 %), saponins (0.25 – 2.40 mg/100g), alkaloids (0.008 – 0.72 %), tannins (100 – 999 mg/g), carbohydrate (0.91 – 1.67 mg/g), acid value (8.40 – 15.60 g/1000cm3, protein (7.30 – 12.10), resins (0.57 – 2.9), and pH (4.10 – 6.72), solubility in cold water at 20oC (0.80 – 10.60 mg/g), solubility in hot water at 100oC (1.99 – 14.25 mg/g), solubility in ether (0.12 – 2.25 mg/g), solubility in 1 % NaOH (10.03 – 38.12 mg/g), Iodine value 16.89mg/g. 22.95 mg/g) saponification values (101.95 mg/g – 197.25 mg/g) flavonoid (0.24 % - 0.96 %), oil content (0.29 % - 1.82 %), cardiac glycoside (0.37 mg/100g – 0.97 mg/100g, fibre saturation point (FSP) (21.0 – 28.50 fatty acid (3.07 – 7.13 %), peroxide value (7.34 mg/g – 10.10 mg/g), calcium (5.594 ppm – 109 ppm), copper (0.004 ppm – 1.075 ppm), potassium (3.577 ppm – 257.296 ppm) cobalt (0.006 ppm – 0.788 ppm), sodium (4798 ppm – 96.366 ppm), magnesium (5.266 ppm – 72.482 ppm), cadmium (0.001 ppm - 0.329 ppm), lead (0.55 ppm – 3.037 ppm), manganese (0.145 ppm – 8.215 ppm), Iron (0.358 ppm – 35.700 ppm). The ANOVA results showed that the concentration of the phytochemical analyses, proximate analyses, polymeric analysis and elemental analysis were significant. The summary of the multiple comparisons showed that protein is most significant among the phytochemical, crude fibre is the most significant among the proximate analysis, lignin is the most significant among the polymeric contents and potassium the most significant among the elemental contents. These results indicated that the fifty tropical wood/timbers had chemical constituents which might be useful to pharmaceutical industries and other industries. From the results obtained, baseline of physicochemicals and heavy metals in tropical timbers have been estimated.