Abstract The effective inhibition of MS corrosion in H2SO4 by CP and CP + KI was assessed by EIS. SM of MS was studied using SEM and AFM. The rise in Rct and decrease in Cdl, with higher C of CP only and CP + KI, confirmed MS CI. IE (%) increased with higher C of CP only and CP + KI (from 10-3 to 10-1 M). CP’s maximum IE (%) was 93.9%, at 10-1 M. CP + KI, due to I- ions synergistic effect, showed an IE (%) of about 98.8% at 10-1 M. CP only and CP + KI adsorption mechanism followed Langmuir’s isotherm. SM studies suggested that a barrier film of CP only and CP + KI, mitigated MS surface corrosion. CP + KI is an efficient inhibitor in H2SO4.

Solid state fermentation was carried out using various agro- industrial wastes with the best amylase producing strain isolated from soil. Different physicochemical conditions were varied for maximum enzyme production. The strain produced about 5400 units/g of amylase at 1:3 moisture content, 20% inoculum, after 72 h of incubation with Mustard Oil seed cake as the substrate. The optimum temperature and pH of the enzyme activity were found to be 50ºC and 6 respectively. The enzyme was found to be thermostable at 70ºC for about 2 h without any salt. It showed stability at pH range 5-7. The metal ions as Na+, Ca++, Mg++ and Co++ enhanced the enzyme activity.