Study On Extraction Process Of Chlorophyll Form Silkworm Excerment By Ultrasonic-assisted Mixed Solvent Method And Residua

Planting mulberries and raising silkworm, which can produce millions of silkworm excrement, has a long history in china, and silkworm excrement is the co-product of sericulture occupation. But nowdays, most of the silkworm excrement is optionally discarded, and it brings a huge pressure to the environment. So it has important realistic and social meaning in this article about studying on development and utilization of silkworm excrement.The ultrasonic-assisted method of chlorophyll has been investigated with silkworm excrement as raw material and petroleum ether-acetone as extraction solvent. By Orthogonal design L25(56), with the extraction rate of chlorophyll as the target, extraction time, extraction temperature, ultrasonic power, material-solvent volume ratio, acetone content and extraction times have been optimized. The optimized ultrasonic-assisted extraction conditions are as follows:four times for extraction,20%for content of acetone,1:4(g:mL)for ratio of material to liquid(petroleum ether:acetone),50min for extraction time,90W for ultrasonic power and50℃for extraction temperature. Under those conditions, the ratio of extraction is reached90.6%. This technology reduces the extraction solvent volatile and extraction temperature, improving the extraction efficiency.Using the residual which has been extracted chlorophyll from silkworm excrement as raw material, it has been studied the preparation of biological adsorption and the application as adsorbing material of dye wastewater.Through orthogonal test, sodium hydroxide as activator, with the adsorption rate of methylthionine chloride as the target, activation temperature, activation time, activator concentration, solid-liquid ratio and soaking time have been optimized in order to get the best conditions about preparation of silkworm excrement biological adsorption. The results show that:the activation temperature600℃, activation time120min, activator concentration30%, solid-liquid ratio1:3, soaking time4h, the orders of the influencing factors of the adsorption rate of methylthionine chloride from silkworm excrement are as follows:activation temperature> activation time> activator concentration> solid-liquid ratio> soaking time.Through the simulation of dyes effluent-acid dyes methyl orange wastewater and alkaline dye crystal violet wastewater, it has been studied its adsorption effect and its adsorption isotherm date. The results show that: adsorption time60min, methyl orange initial concentration20mg·L-1, pH6, silkworm excrement biological adsorbent0.2g, adsorption temperature303K, the removal ratio of methyl orange is85%; adsorption time80min, crystal violet initial concentration100mg·L-1, silkworm excrement biological adsorbent0.2g, adsorption temperature313K, the adsorption quantity of crystal violet is47mg·g-1, and the adsorption isotherm of the two dye wastewater is fitted to the Langmuir equation.Meanwhile, using the residual which has been extracted chlorophyll from silkworm excrement as raw material, it has been studied change of the nutrients in order to achieve the purpose of utilization.