Furfural Extracted from Hickory Hull Optimized by Response Surface Methodology and Its Inhibition Performance

Furfural was extracted from hickory hull in modified sulfuric acid solution and optimized by response surface methodology. The effects of reaction temperature, reaction time and sulfuric mass fraction on the furfural yield and the optimum conditions were evaluated by Box-Behnken central composite experimental design and response surface methodology analysis. The inhibition performance and mechanism of furfural for cold rolled steel in HCl solutions were studied by weight-loss method. Adsorption heat and apparent activation energy were calculated from Van′t Hoff and Arrhenius equations, the mechanism of corrosion inhibition is discussed in detail according to the parameters. The optimum extraction conditions were the reaction temperature of 152 ℃, the reaction time of 2.9 h and the sulfuric mass fraction is 6.9%. Under the optimized conditions, the experimental value of furfural extraction yield was 5.770 6 mg·g-1. The corrosion efficiency of furfural was over 90% in 0.4-2.0 mol·L-1 hydrochloric acid for 0-12 hours at 30-50 ℃, with furfural mass concentration greater than 2 g·L-1. The adsorption of the effective corrosion inhibitor of furfural on cold rolled steel surface was spontaneous and follows the Langmuir adsorption isotherm equation.