共查询到19条相似文献,搜索用时 250 毫秒
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钼酸铵改性膨润土的制备及其对碱性蓝染料的吸附 总被引:1,自引:0,他引:1
针对印染行业废水的污染现状,以钙基膨润土为原料,钼酸铵作为改性剂,制得一种新型水处理剂钼酸铵改性土,对碱性蓝染料印染废水进行处理。经过试验研究,确定了制备的最佳条件:膨润土悬浊液配比为1∶15、钼酸铵溶液质量分数为0.2%、浸泡时间为5min、加热时间为10min。由于钼酸铵聚合体的引入改变了膨润土在水中的分散状态,增强了其对污染物的吸附和离子交换能力。处理后印染废水的脱色率可达96.53%。在此基础上通过建立等温吸附曲线,确定改性膨润土等温吸附线为典型的L-型,属于表面配位吸附。 相似文献
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改性壳聚糖的制备及其对印染废水的脱色处理研究 总被引:1,自引:0,他引:1
研究了改性壳聚糖絮凝剂的微波辐射制备工艺,并将其用于印染废水的脱色处理.通过正交实验,探讨了各种因素对改性的影响,确定了最佳反应条件.结果表明:阳离子醚化剂与壳聚糖量比值1 100、氢氧化钠与阳离子醚化剂量比值为1.2、微波功率360 W、辐射时间4 min时,所得产物的絮凝性能最好.其对印染废水絮凝实验的最佳絮凝条件:改性壳聚糖用量为2 g/L、pH值为6、振荡速度为200 r/min、反应时间为45 min.在此条件下,脱色率达98%以上. 相似文献
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针对膨润土和阳离子淀粉单独用于处理印染废水时存在脱色率低和固液难分离的问题,采用一步法将阳离子淀粉和膨润土同时投入到活性红X-3B的染色废水中,使阳离子淀粉与膨润土相互吸附,形成结构疏松、比表面积较大的阳离子淀粉-膨润土复合絮凝剂,同时吸附废水中的染料,对其进行脱色。以阳离子淀粉-膨润土复合絮凝剂对活性红X-3B染料废水的脱色率为考核指标,经过实验研究,确定了最佳的应用工艺:阳离子淀粉与膨润土在染料废水中的投加量总量为1.25 g/L,阳离子淀粉与膨润土的质量配比为1:1,印染废水的pH 值为7,不添加氯化钠,处理后印染废水的脱色率可达90%以上。在此基础上通过建立等温吸附曲线,确定了阳离子淀粉-膨润土复合絮凝剂的等温吸附线为典型的L-型,属于表面配位吸附。 相似文献
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乙酸均相体系中脉冲电场对壳聚糖降解的影响 总被引:1,自引:0,他引:1
以脉冲电场为处理手段,研究电场强度、处理时间、壳聚糖质量浓度和电导率等因素对壳聚糖大分子降解的影响。结果表明:壳聚糖降解产物的相对分子质量随着电场强度的增大而降低,且在高场强下降解显著,电场强度为33.3kV/cm时,降解率达54.2%;降解速率随处理时间的延长逐渐变缓,前20min和后70min的降解率分别为18.5%和8.5%;而壳聚糖质量浓度和电导率的升高则不利于壳聚糖的降解。傅里叶变换红外光谱分析(FT-IR)分析表明,降解前后壳聚糖的侧链结构未发生改变;原料及经相同方法处理过的降解产物在2θ为10.4°和20.2°处均存在X射线衍射峰,表明产物的晶体结构没有发生明显变化。 相似文献
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通过考察4种澄清剂(壳聚糖、明胶、蛋清、PVPP)及3种助滤剂(水不溶玉米面、硅藻土、皂土)对黍米黄酒的除浊效果和助滤效果,选择了壳聚糖为澄清剂,水不溶玉米面为助滤剂。在此基础上,考察了二者的用量、静置时间等条件对除浊效果的影响,建立了黍米黄酒除浊方法,其壳聚糖用量为0.005 g/L,水不溶玉米面用量为20 g/L,静置时间为1 h,常温条件下过滤。试验结果表明,处理后的黍米黄酒经冷热交替强化试验或放置1年其透光率均>99%,同时其总糖、非糖固形物、总酸、氨基酸态氮含量及感官指标均符合GB/T 13662-2008规定。 相似文献
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味精污水中含有较高的氨氮离子,序列式生物膜反应器(SBBR)能够有效实现味精污水的同步硝化与反硝化反应,减少设备占有面积和节约处理时间。经过实验得出,当溶氧(DO)为3~4mg/L能够有效地满足生物膜中好氧菌的生长需要,又不会破坏生物膜内的厌氧环境,当pH值为8.0时,温度为30℃时,对味精生产中产生的污水的化学需氧量(COD)去除率高达95.34%,氨氮的去除率达到95.78%,生物需氧量(BOD5)去除率94.1%。 相似文献
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改性壳聚糖脱除马氏珠母贝糖胺聚糖中镉的初步研究 总被引:1,自引:0,他引:1
采用L-半胱氨酸改性壳聚糖对马氏珠母贝糖胺聚糖中的重金属镉离子进行脱除研究,通过单因素实验和正交实验探讨了pH、反应时间和改性壳聚糖的添加量对糖胺聚糖中镉离子的脱除率和糖胺聚糖(GAG)含量的影响,并且利用SPSS对正交实验的数据进行处理分析,结果表明:在马氏珠母贝酶解液中添加L-半胱氨酸改性壳聚糖吸附镉离子的最佳pH为6.0,时间为5h,添加量为0.6g/50mL,然后将酶解液经离心、醇沉得到的糖胺聚糖中镉离子的脱除率达到56.7%,GAG含量为42.8%。 相似文献
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为了降低制糖过程中蔗汁中酚类化合物的含量,本研究以壳聚糖和沸石为原料,通过共沉淀法制备壳聚糖改性沸石,研究改性前后沸石表面结构和基团的变化,考察时间、p H及酚酸初始浓度等因素对改性沸石吸附蔗糖溶液中酚酸吸附效果的影响,并对吸附动力学模型和吸附等温模型进行初步探讨。扫描电镜结果显示壳聚糖改性后沸石表面更加粗糙,红外光谱显示改性后复合材料基团发生了改变,壳聚糖成功地负载到了沸石上。吸附试验结果表明壳聚糖改性可以提高沸石对酚酸的吸附能力,改性沸石对酚酸吸附的最佳p H值为8.0,吸附时间为600 min,此时酚酸吸附量达到了33.41 mg/g;酚酸初始浓度的提高有利于提高吸附效果;吸附过程符合准二级吸附动力学模型和Langmuir等温吸附模型。壳聚糖改性沸石对蔗糖溶液中酚酸吸附效果良好,是一种有前景的糖用澄清剂。 相似文献
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目的:研究磁性壳聚糖改性高岭土对模拟蔗汁中咖啡酸的吸附特性。方法:通过共沉淀法将壳聚糖、纳米四氧化三铁与高岭土结合制备成磁性壳聚糖改性高岭土,通过FT-IR、VSM和SEM表征高岭土改性前后表面结构和基团变化,采用吸附试验研究磁性壳聚糖改性高岭土对咖啡酸的吸附特性。结果:改性后壳聚糖和纳米Fe3O4成功地负载到了高岭土上并提升了其对咖啡酸的吸附性能,磁性壳聚糖改性高岭土的等电点为4.54,酸性条件有利于咖啡酸的去除,并在240 min时达到吸附平衡。磁性壳聚糖改性高岭土对咖啡酸的吸附过程更符合准二级动力学和Langmuir等温线吸附模型,其吸附过程主要为化学吸附和单分子层吸附,热力学研究表明吸附过程为自发吸热过程。结论:磁性壳聚糖改性高岭土对蔗汁中咖啡酸具有较强吸附性能,可作为糖用澄清剂用于蔗汁中咖啡酸的吸附处理。 相似文献
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《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2013,30(7):1168-1174
The ability of several oenological fining agents to remove ochratoxin A (OTA) from red wine was studied. The adsorbents tested were activated sodium bentonite, egg albumin, allergen-free adsorbents (complex PVPP, plant protein and amorphous silica (complex) and high molecular weight gelatine), and the non-toxic biodegradable polymers (chitin and chitosan). Several dosages within the oenological use range were tested and the wine pH, colour parameters and polyphenol concentration impact associated with each fining agent were studied. Generally, OTA removal achieved in all treatments was higher when the adsorbent dosage increased, but the impact on wine quality also was higher. Chitin at 50?g?hl?1 removed 18% the OTA without affecting significantly the wine-quality parameters. At the highest dosage tested the gelatine and complex treatments achieved greater OTA removal (up to 39–40%) compared with bentonite, egg albumin and chitin. Moreover, the gelatine and the complex had a lower impact on colour parameters and polyphenol concentration compared with chitosan, whilst OTA was reduced to around 40%. Chitosan achieved the greatest OTA removal (67%), but it strongly affected the wine-quality parameters. Otherwise, bentonite showed a relative efficiency to remove OTA, but the CI value decreased considerably. The egg albumin treatment only removed OTA up to 16% and moreover affected strongly the CI value and CIELab parameters. The results of this survey showed that the non-toxic chitin adsorbent and the allergen-free adsorbents tested could be considered as alternative fining agents to reduce OTA in red wine. 相似文献
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Quintela S Villarán MC López De Armentia I Elejalde E 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2012,29(7):1168-1174
The ability of several oenological fining agents to remove ochratoxin A (OTA) from red wine was studied. The adsorbents tested were activated sodium bentonite, egg albumin, allergen-free adsorbents (complex PVPP, plant protein and amorphous silica (complex) and high molecular weight gelatine), and the non-toxic biodegradable polymers (chitin and chitosan). Several dosages within the oenological use range were tested and the wine pH, colour parameters and polyphenol concentration impact associated with each fining agent were studied. Generally, OTA removal achieved in all treatments was higher when the adsorbent dosage increased, but the impact on wine quality also was higher. Chitin at 50 g hl(-1) removed 18% the OTA without affecting significantly the wine-quality parameters. At the highest dosage tested the gelatine and complex treatments achieved greater OTA removal (up to 39-40%) compared with bentonite, egg albumin and chitin. Moreover, the gelatine and the complex had a lower impact on colour parameters and polyphenol concentration compared with chitosan, whilst OTA was reduced to around 40%. Chitosan achieved the greatest OTA removal (67%), but it strongly affected the wine-quality parameters. Otherwise, bentonite showed a relative efficiency to remove OTA, but the CI value decreased considerably. The egg albumin treatment only removed OTA up to 16% and moreover affected strongly the CI value and CIELab parameters. The results of this survey showed that the non-toxic chitin adsorbent and the allergen-free adsorbents tested could be considered as alternative fining agents to reduce OTA in red wine. 相似文献