铬鞣剂再生循环利用研究

Study on Recycling of Chrome Tanning Agent

利用改性Pd/AC催化剂对铬鞣污泥中的胶原蛋白等有机物进行催化分解,释放出铬鞣污泥中的铬并配制成铬鞣剂加以循环利用.其最佳的实验条件为:温度450℃,Pd/AC催化剂加入量1.5%(以污泥干料质量计),加热时间3h。铬渣浸于p H值=2.0的稀H2SO4溶液2h,减压抽滤后得到纯化铬液,铬回收率超过98%,有机物成分低于0.2%。纯化铬液配制成质量分数为3.5%(以Cr2O3计)的再生铬鞣剂鞣制皮革,牛皮蓝湿革收缩温度大于98℃,手感柔软、丰满,质地均匀。

On the modified Pd / AC catalyst,collagen and other organic matters was decomposed and chromium was released from the chrome tanning sludge. And made into chrome tanning agent to recycle it. The optimum conditions of experiment as follows：Catalytic temperature was 450℃,catalyst addition was 1. 5%（ measured by sludge powder）,time was 3h for the chemical decomposition. Chrome slag was immersed in the solution of H2SO4（ p H = 2. 0） 2h. We obtained the purified chrome liquid after vacuum filtering. The recovery rate of chromium was higher than 98% and the percent of organic matters were less than 0. 2%.We prepared the 3. 5%（ measured by Cr2O3） regeneration chrome tanning agent using recovery chromium liquid. After tanned by the agent,the blue wet cowhide ＇s shrinkage temperature was greater than 98℃ and it became soft,fullness and uniformity in texture.