Lyocell纤维的漂白工艺

建立了一种应用于Lyocell纤维的新型漂白工艺 分析了漂白液中的过氧化氢质量分数、漂白时间、pH值、漂白温度、稳定剂质量分数对Lyocell纤维的白度和干断裂强度的影响.在确定的漂白工艺四步骤中第一步为预漂白,加入了稳定剂DELINOL9258,增加了漂白效果.漂白步骤最佳优化条件是：过氧化氢质量分数0.8％,漂白时间50 min,漂白液pH值11,漂白温度80℃,稳定剂LAVATEX9188质量分数0.3％     

Lyocell纤维的漂白工艺

建立了一种应用于Lyocell纤维的新型漂白工艺。分析了漂白液中的过氧化氢质量分数、漂白时间、pH值、漂白温度、稳定剂质量分数对Lyocell纤维的白度和干断裂强度的影响。在确定的漂白工艺四步骤中第一步为预漂白，加入了稳定剂DELINOL 9258，增加了漂白效果。漂白步骤最佳优化条件是：过氧化氢质量分数0.8 %，漂白时间50 min，漂白液pH值11，漂白温度80 ℃，稳定剂LAVATEX 9188质量分数0.3 %。     

白杨木粉碱性过氧化氢漂白条件的优化

研究了碱性条件下过氧化氢对杨木木粉的漂白工艺,探讨漂白温度、漂白时间、H₂O₂用量、pH值及偏硅酸钠用量对白度的影响。结果表明,过氧化氢对杨木木粉漂白的最佳工艺条件为:H₂O₂用量为40%,Na₂SiO₃·9H₂O用量为8%,pH值为10~11,漂液温度在60~70℃,漂白时间40 min。该工艺对杨木粉进行漂白,最高白度可达到85%~90%(ISO),高于文献上报道的H₂O₂漂白白度。     

非硅过氧化氢稳定剂在桉木TMP浆漂白过程中的应用研究

以桉木热磨机械浆(TMP浆)为研究对象, 探讨了非硅过氧化氢漂白稳定剂G1、G56替代硅酸钠用于桉木TMP浆漂白的可行性, 并对漂白工艺条件进行了优化。结果表明:桉木TMP浆过氧化氢漂白采用稳定剂G1、G56替代硅酸钠是可行的。在浆浓(质量分数)20%、H₂O₂用量9.0%(以绝干浆质量计,下同)条件下优化的漂白工艺条件为:G1用量0.5%, G56用量0.5%, NaOH用量5.85%, 温度90 ℃和时间30 min。在此工艺条件下桉木TMP浆单段过氧化氢漂白后, 浆的白度达到77.47% (ISO), 比原浆白度高38.89个百分点, 比2%硅酸钠用量下漂后浆的白度高1.75个百分点, 与2%硅酸钠和2%DTPA同时用作稳定剂的白度(79.88%(ISO))相当。     

预处理和添加硅酸钠对草浆过氧化氢漂白的影响

对酸处理 /螯合处理过程中pH值变化以及硅酸钠的使用对麦草浆和蔗渣浆过氧化氢漂白的影响进行了研究。结果表明 ,在pH值为 3时螯合处理能够使各浆料获得最佳白度 ;硅酸钠可抑制过氧化氢漂白中纤维素的降解 ,提高纸浆粘度 ,并可使Si和Mg含量较低的蔗渣浆提高白度。     

废报纸脱墨浆两段漂白工艺研究

研究了废报纸脱墨浆过氧化氢―过氧化氢(PP)、过氧化氢―甲脒亚磺酸(PF)两段漂白工艺。结果表明,废报纸脱墨浆PP漂白中第二段过氧化氢漂白的适宜工艺条件为:浆浓20%,漂白时间2.5 h,温度60℃,乙二胺四乙酸(EDTA)用量0.2%,硫酸镁用量0.05%,硅酸钠用量0.5%,过氧化氢用量4%,氢氧化钠用量0.5%,漂后浆白度71.5%(ISO);PF漂白中第二段甲脒亚磺酸漂白的适宜工艺条件为:漂白温度60℃,漂白时间40 min,浆浓10%,甲脒亚磺酸(FAS)用量1.6%,NaOH用量0.8%,漂后浆白度68%(ISO)。     

利用二氧化硫脲还原-络合漂白花岗斑岩

以浮梁县鹅湖镇花岗斑岩为研究对象,二氧化硫脲为还原剂、EDTA为络合剂对花岗斑岩进行还原-络合漂白,系统研究了漂白工艺条件对漂白效果的影响。研究结果表明,络合-还原漂白法只能除去花岗斑岩的表面铁,使得其自然白度有一定的提升;最佳漂白工艺条件为：pH=10、温度70℃、EDTA用量7.5 wt%、二氧化硫脲用量2.5 wt%,反应时间20 min;在最佳工艺条件下,花岗斑岩的自然白度由原来的62.65%提升至72.19%,铁含量由1.66%降到1.29%,除铁率为22.29%。     

糠醛渣制备羧甲基纤维素的研究

以糠醛渣为原料,采用Milox法提取纤维素,经漂白处理后制备羧甲基纤维素(CMC),对纤维素提取工艺、漂白工艺及CMC的合成进行了初步研究。实验结果表明,纤维素提取工艺优化条件:甲酸80mL,过氧化氢14mL,反应时间2.5h—2.5h—2.5h,反应温度80℃—95℃—80℃;漂白工艺条件:可选择过氧化氢10mL,氢氧化钠质量浓度2.5g/L,反应温度45℃,反应时间60min。制得的CMC的取代度为0.901 2,黏度为45mPa·s。     

新型吸附材料制备及处理含DMAC废水试验研究*

合成了主要成分为粉煤灰和活性炭的新型吸附材料,并通过单因素试验考察了吸附材料处理含DMAC（N, N-二甲基乙酰胺）废水的效果。吸附材料最佳制备条件：粉煤灰与活性炭质量比为3∶1,硅酸钠加入量为25%（硅酸钠占粉煤灰、活性炭、硅酸钠总质量的质量分数）,煅烧温度为800 ℃。吸附材料处理含N, N-二甲基乙酰胺废水最佳条件：pH为3,吸附剂投加量为25 g/L,吸附时间为40 min,吸附温度为30 ℃,在此条件下CODCr去除率为75.92 %。     

全棉筒子纱氧漂工艺的生产实践

为提高漂白全棉筒子纱的白度、强力、毛效等指标,在生产中探讨了水质、过氧化氢用量、漂液pH值、氧漂温度、氧漂时间对筒子纱性能的影响,得出了全棉筒子纱的最佳氧漂工艺。其中27%双氧水浓度12～13 g/L,pH值10.5～11.5之间,氧漂温度与时间控制98±2℃,55分钟。在此工艺下,全棉筒子纱的白度、强力、毛效获得最佳协同效果,可满足客户要求。     

Effect of hydrogen peroxide bleaching onto sulfonated jute fiber

Bleaching of raw and sulfonated jute fiber with hydrogen peroxide were carried out in an aqueous medium. To obtain the optimum condition for bleaching, the effects of hydrogen peroxide concentration, temperature, time, pH, and fiber–liquor ration were studied. Bleaching affected the whiteness and tenacity, and the optimum whiteness index (76) and tenacity (13.7 g/tex) for the bleached sulfonated jute fiber were obtained with 2.1% hydrogen peroxide at pH 11, temperature 95°C, treatment time 110 min, and fiber–liquor ratio 1 : 7. The photo‐oxidative degradation of bleached sulfonated jute fiber was characterized by UV light exposure and compared with that of bleached raw jute fiber. It has been observed that the photo‐oxidative degradation as well as loss in tenacity and yellowness of the bleached sulfonated jute fiber was 63 and 40% lower than that of bleached raw jute fiber. Bleached sulfonated jute fiber had excellent impact on color fastness with reactive dyes. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 99: 3603–3607, 2006     

高收率高稳定性过碳酸钠的制备

以碳酸钠和双氧水为原料制备过碳酸钠。考察了反应温度、反应时间、原料配比、后处理工艺等因素对过碳酸钠产品收率和稳定性的影响。适宜工艺条件：反应温度为15 ℃、反应时间为30 min、复合稳定剂（聚丙烯酸钠-硅酸钠-硫酸镁）加入量为碳酸钠质量的1%、碳酸钠与双氧水物质的量比为1∶（1.5~1.6）。在此条件下,制得过碳酸钠产品活性氧含量较高。结晶后,利用双氧水溶液对晶粒进行洗涤,于50 ℃下干燥3 h,过碳酸钠产品收率可达到88%,活性氧质量分数可达到14.75%。过碳酸钠产品存储35 d后,活性氧质量分数仍可达到13.90%,稳定性较好。     

吐温80对麦草浆过氧化氢漂白的促进作用

研究了表面活性剂吐温80(Tween 80,聚氧乙烯山梨醇酐单油酸酯)在麦草浆过氧化氢漂白中的助漂作用。对OQP/T、OQPT和OQTP三种OQP与表面活性剂Tween 80配合漂白工艺的对比结果表明,OQP漂白后再采用表面活性剂Tween 80辅助漂白可获得较好的漂白效果。当表面活性剂用量为0.8%时,其漂白浆白度可达75.2%,黏度为794 mL/g,表明Tween 80有明显的辅助漂白作用。在此条件下,漂白浆的耐破强度、撕裂强度较对照OQP漂白浆有显著提高,而抗张强度基本不变,仅耐折强度有所下降。     

An evaluation of the effectiveness of applying a gelatin–copper complex in the low-temperature bleaching of cotton with hydrogen peroxide

A gelatin–copper complex was prepared and then added as catalyst to a hydrogen peroxide bleaching bath. Cotton fabric was bleached with the new system at low temperature (70 °C). The effects of the gelatin–copper complex on the whiteness, capillary effect, damage, and bleaching rate of the bleached fabric and on the decomposition ratio of hydrogen peroxide were evaluated. These effects were compared with the effectiveness of traditional high-temperature bleaching and low-temperature bleaching without the gelatin–copper complex. The results showed that the gelatin–copper complex enhances the bleaching effectiveness of hydrogen peroxide. The whiteness of cotton fabric bleached with the catalytic complex is comparable with the whiteness achieved with a conventional peroxide system. The catalytic bleaching technology not only realises low-temperature and low-alkali bleaching of cotton with hydrogen peroxide but also reduces fabric strength loss, which meets the requirements of industry for continued development of the wet processing of textiles.     

废纸脱墨浆H_2O_2漂白的影响因素

研究了脱墨浆过氧化氢漂白特性。研究结果表明 ,脱墨浆采用过氧化氢漂白时 ,过氧化氢的无效分解的程度大。脱墨浆采用过氧化氢漂白时 ,过氧化氢同氢氧化钠用量比为 1∶0 .6,漂白反应时间为 2h ,漂白反应温度为 70℃ ,浆浓为 1 0 %比较合适     

Improving the photostability of bleached silk without reducing its whiteness

Bleached silk is rapidly yellowed by exposure to the ultraviolet radiation present in sunlight. The conventional application of a water‐soluble hydroxyphenyl benzotriazole ultraviolet absorber (such as UVFast W) to bleached silk reduces its rate of photoyellowing but has a negative impact on the whiteness of the bleached silk, largely cancelling out the improvements in whiteness achieved during bleaching. Therefore, a series of bleaching processes and aftertreatments using UVFast W on silk were investigated, with the measurement of reflection spectrum, whiteness, yellowness, and strength before and after exposure to ultraviolet radiation. The results show that whiteness of silk treated by oxidation–reduction double bleaching can be increased, and the whiteness of double‐bleached silk with 4% UVFast W aftertreatment was even slightly higher than that of the hydrogen‐peroxide‐bleached silk. After ultraviolet irradiation, double‐bleached silk samples with 4% UVFast W treatment resulted in both the highest whiteness and optimum photostability by comparison with unbleached standard silk and hydrogen‐peroxide‐bleached silk samples with and without 4% UVFast W treatment, and its strength difference was superior to the samples, except for standard silk with 4% UVFast W treatment after exposure to UV radiation for 18 h.     

酸碱结合预处理对水稻秸秆纤维素乙醇转化率的影响

以水稻秸秆为原料．在常温常压条件下分别用乙酸、过氧化氢、乙酸-过氧化氢（PPA）、氢氧化钠-PAA进行预处理,然后加入纤维素酶和酵母进行异步发酵产乙醇。结果表明,酸碱结合（氢氧化钠～PPA）处理后的固体得率显著低于乙酸或过氧化氢的单独处理,固体得率和纤维素水解后产生的葡萄糖浓度呈负相关;氢氧化钠-PAA处理能有效去除水稻秸秆中的木质素．大幅提高纤维素水解率和乙醇转化率;用10％氢氧化钠-PAA室温浸泡处理水稻秸秆48h与用5％氢氧化钠-PAA90℃处理水稻秸秆1．5h具有同样的效果。