Abstract:
The thermodynamic studies relating to the activated complex for the heterogeneous dilute indigenous carbonate salt hydrolysis of two non-woody ligno-cellulosic plant residues has been determined. The study was carried out on three indigenous basic salts; pH, percent concentration of CO32-, and HCO3- and the degree of hydrolysis data are presented for three salt samples from Lake Magadi, Shores of Lake Victoria and the Hot Springs of the Kerio Valley Kenya. All treatments were done in triplicate in complete randomized block design. Fresh and dry weight were recorded at the end of the experiment and analyzed for anions; CO32-, and HCO3- and pH values determined. Trace, anions, pH and structure of three different indigenous basic salts commonly available in Kenya namely ‘Para’, “magadi’, and ‘Lebek’, salts were quantitatively and qualitatively analyzed using FTIR and the wet methods; Gravimetry and titrimetry. The pH values ranged from 9.98±0.01 to 11.26 ± 0.03 for magadi salt, 10.08 ± 0.03 to 10.88 ± 0.06 for Para salt and 10.09 ± 0.02 to 10.85 ± 0.06 for Lebek salt. Thus all the salts were alkaline. The bicarbonate concentration ranged from the highest of 25.3 ± 0.3% in magadi salt, to the lowest of 6.2 ± 0.1% in Lebek salt. Degree of hydrolysis for gallants soldier (GS) lignocellulosic sample ranged from the highest of 44.99 ± 0.03% with Magadi salt to the lowest of 29.98 ± 0.05% in Lebek salt. Hydrolysis with wheat straw (WS) lignocellulosic sample ranged from the highest of 30.75±0.05% with Magadi salt to the lowest of 20.94 ± 0.01% Lebek salt. All salts had higher bicarbonate percent concentration values higher than carbonate percent concentration values. This clearly showed the role of the bicarbonate group in lignocellulosic hydrolysis. Lower the pH values, the lower the bicarbonate and the higher the degree of hydrolysis. FTIR analysis showed presence of bicarbonate group in all the salts. Key words: Indigeneous salts; pH; Characterisation; Bi-carboate; carbonate; Hydrolysis
