Study On Adsorption Properties Of Blueberry Pomace

In this paper,blueberry pomace is used as raw material,and the extraction and preparation process of dietary fiber is studied,and the extraction parameters of soluble dietary fiber（SDF）are optimized by response surface methodology.Rapid pyrolysis method was used to prepare biochar（IDFB）,and the microstructure and surface functional groups of dietary fiber and IDFB were studied by scanning electron microscope and Fourier transform infrared spectrometer,and thenthe physico Chemical properties of SDF and its effect on Cu2+and ions in simulated gastrointestinal environment were studied.The adsorption effect of Cd²⁺,and the adsorption effect of IDFB on P⁵⁺、Cu²⁺and Cd²⁺in wastewater were detected,hoping to provide reference for the comprehensive utilization of blueberry pomace.The specific research results are as follows:（1）The factors affecting the yield of blueberry pomace（Y）were microwave time（X₂）>enzymolysis time（X₄）>enzymolysis temperature（X₃）>enzyme addition（X₁）.The response surface equation between SDF yield and each factor is Y=11.86-0.025X₁+0.18X₂-0.033X₃-0.16X₄+0.075X₁X₂+0.17X₁X₃+0.27X₁X₄-0.20X₂X₃+0.17X₂X₄+0.22X₃X₄-0.76X₁²-0.74X₂²-0.84X₃²-0.55X₄².The optimal extraction process parameters of SDF were 4%enzyme addition,20s microwave time,55℃enzymolysis temperature and 70min enzymolysis time.（2）The water holding capacity of blueberry pomace SDF is 30.46g/g,the swelling degree is 40.67m L/g,and the oil holding capacity is 5.43g/g;The preparation rate of IDFB was 61.17%;compared with the surface structure of IDF,the cavities formed by SDF and IDFB were denser,the surface area was larger,and the pores were deeper,and the surface of blueberry pomace SDF,IDF and IDFB contained hydroxyl and carboxyl groups,and no new covalent bonds were formed.（3）Under the simulated gastric environment in vitro,the adsorption of SDF on Cu²⁺and Cd²⁺reached a dynamic equilibrium at 70 min.When the amount of SDF added was 0.1 g/100m L,the adsorption amounts were 36.5413 mg/g and 25.1625mg/g,respectively.When the initial concentration was 50 mg/L,the adsorption rates were 92.98%and 84.17%,respectively.Under the simulated intestinal environment in vitro,the adsorption of Cu²⁺and Cd²⁺ by SDF reached a dynamic equilibrium at 70 min.When the SDF addition amount was 0.1 g/L At 100 m L,the adsorption amounts were 29.1675 mg/g and 38.1864 mg/g,respectively.When the initial concentration was 50 mg/L,the adsorption rates were 93.58%and 95.66%,respectively.（4）The adsorption of IDFB to P⁵⁺reached a dynamic equilibrium at 100 min.When the addition amount was 0.05 g/50 m L,the adsorption amount reached 4.6535mg/g.When the initial concentration was 2 mg/L,the adsorption rate was 97.36%;The adsorption of Cd²⁺reached a dynamic equilibrium at 70 min.When the addition amount was 0.1 g/100 m L,the adsorption amounts were 21.6675 mg/g and 19.9845mg/g,respectively.When the initial concentration was 50 mg/L,the adsorption rates were 80.93%.and 84.17%.（5）Under the simulated gastrointestinal environment in vitro,the adsorption of SDF to Cu²⁺and Cd²⁺conformed to the pseudo-second-order kinetic model,and there was an intra-particle diffusion process.The adsorption mechanism of Cd²⁺is similar,which also conforms to the pseudo-second-order kinetic model and the existence of intraparticle diffusion process.