共查询到19条相似文献,搜索用时 125 毫秒
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化学镀镍废水处理研究 总被引:5,自引:0,他引:5
1.前言自五十年代以来,化学镀镍作为一种新型表面处理工艺出现,其应用范围不断扩大,已深入到化学工业、汽车工业、电子工业等各个部门。化学镀镍废水中含有大量的镍离子、次亚磷酸根离子、亚磷酸根离子及多种有机物,若废液处理不当必将造成严重的污染。国外有关人员曾专门研究了化学镀镍废液对鱼类的危害,见[3]、[4]、[5]。对于化学镀镍废液处理的研究是近二十年才开始的。目前各国提出的处理方法主要有化学沉淀法、电解镍回收离子交换法、旋转电极法、电渗析法及反渗透法等。各种处理方法用于不同场合,且各有利弊,化学沉淀法是一种… 相似文献
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针对化学镀镍废液中存在大量可再生利用的金属镍资源,采用正交实验法和TEM,XRD,XRF等分析手段,系统研究了化学镀镍废液中镍离子硼氢化钠催化还原回收工艺。实验结果表明:回收工艺中各因素对产量影响的显著性顺序为硼氢化钠的体积浓度、反应温度、pH值、KH570的质量浓度;不同分散剂对回收产物产量和粒度影响不同,其中,使用KH570得到的回收产物的产量最大,粒度分布也较集中。推荐化学镀镍废液较优回收工艺为:硼氢化钠140mL/L,KH5703g/L,温度40℃,pH值5。按该工艺所回收的产物平均粒径为70nm,含有镍、硼和磷等元素,并且由镍-硼和镍-磷非晶态合金组成,处理后废液中镍离子的质量浓度低于1mg/L,其回收率接近100%。 相似文献
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采用电渗析法研究了化学镀镍废液的再生工艺,研究分析了离子交换膜的选择方法,以及电流密度和处理时间对镀液中不同离子去除(损失)率的影响。结果表明,以日本的CMS离子交换膜和上海的异相阴离子交换膜组成的膜对作为离子交换膜,在65mA/cm2下对化学镀镍废液处理48h时的再生效果较好,23HPO的去除率达60.86%,22HPO和Ni2+的损失率分别为63.13%和1.20%。经本法处理并补加有效成分22HPO之后,可从再生化学镀镍液中制得性能良好的镍镀层,即化学镀镍废液得到回用。 相似文献
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离子交换法再生脱硫胺液 总被引:1,自引:0,他引:1
炼厂脱硫装置的贫液中的热稳态盐不断累积,其中累积速度最快的是焦化装置和催化装置。阴离子交换树脂可以再生脱磺胺液,除去胺液中的热稳态盐阴离子,考察了多种阴离子交换树脂的使用寿命。实验结果表明,ZX3#树脂好于进口树脂,可以长期再生含热稳态盐高的胺液(HSS〉3%),经过重复吸附脱附(〉4000次)交换容量仍然保持在新鲜树脂的50%以上。离子交换树脂应用于胺液再生,容易失效的主要原因是有机物污染和破碎,可以采用5%~20%的氯化钠溶液进行复苏,延长树脂的使用寿命。用离子色谱法可以分析胺液中热稳态盐的离子组成。 相似文献
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分别采用有机溶剂萃取法、超滤法、大孔树脂吸附法、离子交换法分离提取亚硫酸氢镁预处理麦秆废液中的木质素磺酸盐和低聚木糖。研究结果表明超滤法不能达到分离目的,有机溶剂沉淀和大孔树脂吸附可实现木质素磺酸镁的纯化,采用D380离子交换树脂进行离子交换层析可将废液中低聚木糖和木质素磺酸镁完全分离,回收所得低聚木糖和木质素磺酸盐纯度分别可达63.95%和91.28%。因此,D380树脂固定床离子交换法是一种简单有效的提取废液中高附加值产品的方法,可实现亚硫酸氢镁预处理麦秆废液的高值化利用,具有强劲的市场应用潜力。 相似文献
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采用201′7树脂对拜耳法生产Al2O3流程中种分母液沉钒后再浸出,对制得的Na2VO4溶液进行了静态吸附动力学研究,分析了吸附机理. 采用批式离子交换法,考察了树脂粒径、温度、搅拌速率、溶液浓度对离子交换过程的影响,并用动边界模型对树脂吸附钒的离子交换过程进行了描述. 结果表明,离子交换过程由颗粒内扩散控制,搅拌速率和反应温度对交换速率影响较小,吸附速率随Na2VO4溶液中钒初始浓度的增加而升高;交换过程的反应速率常数为10.052 cm4/(mol×s),反应级数n为0.5507,表观活化能为39.67 kJ/mol. 吸附机理分析结果表明,在动力学实验过程中201′7树脂主要吸附的钒阴离子为V10O286-. 相似文献
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Gel permeation chromatography of spent liquors from oxygen bleaching showed that cleavage of covalent linkages in the fiber was a prerequisite for the dissolution of the lignin. The reactions continued in the liquor phase. The cleavage was related to the oxidation of the lignin. With pulps pretreated with nitrogen dioxide an appreciable number of lignin linkages were cleaved also by the direct influence of the hydroxide ions on the nitrated lignin. In the alkaline medium the acidic sites in the fiber and in dissolved lignin fragments are ionized. Donnan-exclusion and an increased fiber swelling promote the transfer of the fragments into the liquor. Hydrophilic groups introduced into the lignin during oxygen bleaching promote the delignification. 相似文献
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Spent reactive dyebaths were decolorised by treatment with ozone and reused in the bleaching, whitening and dyeing of two textile substrates. The study shows that the reuse of a spent dyebath is possible with little modification to the standard processes for dyeing cotton with reactive dyes, provided that the pH of the treated dyebath is adjusted. Moreover, the cycle of decolorisation and reuse was successfully repeated. Renovated reactive dyebaths were also reused for bleaching cotton fabric with hydrogen peroxide, whitening with optical brightener and dyeing polyester fabric with disperse dyes. The whiteness index of bleached and whitened cotton was comparable to that of the same fabric given a control treatment with fresh baths. Likewise, there was a negligible colour difference between polyester dyed using liquor from a spent reactive dyebath and the same fabric dyed in a new bath. 相似文献
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Chlorinated organic matter is formed during chlorine bleaching of carbohydrate. After chlorine bleaching of various cellulosic materials, organochlorine is found in the cellulose substrate (e.g., about 490 μg Cl/g substrate for cotton cellulose) as well as in the spent bleaching liquor. Some organochlorine is mineralized by alkali treatment of the cellulose and some is dissolved. Some organochlorine is not removed by exhaustive extraction with organic solvents, i.e., is inextractable. The carbohydrate-originated organochlorine accounts for part of the inextractable organochlorine in fully-bleached chemical pulp (previously ascribed entirely to a lignin origin). Chlorination of unmodified simple sugars results in some organochlorine (17 to 83 μg Cl/g sugar), while chlorination of “kraft-cooked” glucose precipitate results in 6150 μg organochlorine as Cl/g substrate. Household hypochlorite bleaching of cotton fabric also results in formation of inextractable organochlorine. 相似文献