紫胶全无氯漂白的漂前预处理工艺开发与优化  

Development and Optimization of Pretreatment Technique of Total Chlorine Free Bleaching of Shellac

作　　者：李坤[1,2,3] 郑华[1,2,3] 张雯雯[1,2] 张弘[1,2,3] 李凯[1,2] 徐涓[1,2] 

机构地区：[1]中国林业科学研究院资源昆虫研究所 [2]国家林业局特色森林资源工程技术研究中心 [3]国家林业局资源昆虫培育与利用重点实验室,云南昆明650224

出　　处：《环境科学与技术》2016年第7期127-134,共8页Environmental Science & Technology

基　　金：国家高技术研究发展计划("863"计划)项目(2014AA021801);中央级公益性科研院所基本科研业务专项(riricaf2014005M)

摘　　要：该研究旨在明确紫胶的漂前处理工艺尤其是盐析工艺对析出紫胶树脂钠盐得率和紫胶红色素去除效果的影响,进而为漂白效果的改善提供数据支撑。首先,通过单因素试验研究了盐析温度、盐析剂浓度、p H值、盐析时间对盐析效果的影响,再以响应曲面法对盐析工艺进行了优化,并在此基础上明确了最佳工艺条件下的洗涤级数及析出紫胶树脂钠盐的性质。结果表明:紫胶无氯漂白前处理的最佳工艺为,盐析温度10℃,盐析剂浓度0.250 1 g/m L,盐析时间4 h,p H值10.0,紫胶树脂钠盐的洗涤级数为4时最佳,蒽醌含量由原胶的1.445%降低至0.505%;FTIR、DSC数据表明:盐析工艺并未改变紫胶树脂的主体分子结构,但紫胶树脂钠盐的热性质较紫胶树脂有所提高,熔融峰值由66.1℃升高至76.5℃。可见,作为前处理的紫胶盐析工艺为降低紫胶树脂中蒽醌色素的含量,减少后续漂白剂的用量作用显著。The purpose of this study was to define the influence on the pretreatment process of shellac bleaching,especially precipitation process,to the yield of shellac sodium and removal rate of lac dye. Moreover,it could provide better data support to the bleaching technique. Firstly,the influence of single factors including concentration of sodium chloride,p H value,precipitation time and temperature,on precipitation effect was investigated by the single factor experiment. And then,response surface method was used to the optimization process. Washing series and properties of shellac sodium were obtained based on the optimal process. Results show that the optimal technique of shellac bleaching was precipitation temperature at10 ℃;concentration of sodium chloride 0.250 1 g/m L,precipitation time 4 h,p H value 10.0,the optimal washing series 4,and total anthraquinones content in the sticklac descend from 1.445% to 0.505%. FTIR and DSC characterization showed that the main structure of shellac resin was not changed in the precipitation process but the thermal properties of shellac sodium were better than shellac resin. For instance,melting peak point raised from 66.1 ℃ to 76.5 ℃. It followed that the impact was significant on the decrease of total anthraquinones content in the sticklac and dosage of bleaching agent through pretreatment technique.

关 键 词：紫胶 全无氯漂白 前处理 工艺优化 

分 类 号：X383[环境科学与工程—环境工程]