壳聚糖/Ni-TiO2复合絮凝剂对印染废水的处理研究

利用溶胶-凝胶法制备壳聚糖/Ni-TiO2复合絮凝剂,去处理模拟印染废水。用可见分光光度测定法对甲基橙的含量进行了测定,考察了壳聚糖/Ni-TiO2复合絮凝剂投加量、反应时间、反应温度、pH值对废水处理效果的影响。结果表明:在超声波频率为50kHz时,甲基橙溶液初始浓度为25mg/L,溶液pH=6,壳聚糖/Ni-TiO2复合絮凝剂的加入量为0.1g,时间60min,温度为40℃,甲基橙溶液脱色率到达到95.0%以上。同时,壳聚糖/Ni-TiO2复合絮凝剂处理甲基橙溶液时,不仅有吸附作用的存在,同时还有光催化降解的作用。     

新型絮凝剂PSAM-CTS处理松花江水的研究

制备了一种新型聚硅酸铝镁-壳聚糖(PSAM-CTS)复合絮凝剂,并将其用于处理松花江江水。考察了投加量、水样pH值、水温等因素的影响。结果表明:当投加量为1mL,待处理水样为500mL时,PSAM-CTS絮凝剂呈现很好的絮凝脱色效果,适用于处理低温(0~5℃)、偏碱性(pH=7~9)的松花江水。用扫描电镜观察PSAM-CTS絮凝剂的微观形貌,X-射线衍射分析了聚硅酸、壳聚糖、金属离子水解产物三者之间的作用情况。     

氢氧化镁/壳聚糖复合絮凝剂处理模拟印染废水的研究

采用氢氧化镁/壳聚糖复合絮凝剂处理模拟印染废水,考察pH值、复合絮凝剂投加量、质量配比(m壳聚糖∶m镁盐)等条件对模拟印染废水吸附效果的影响,并通过正交试验确定最佳吸附条件及主要影响因素。结果表明:最佳吸附条件为模拟印染废水pH值11.0,复合絮凝剂投加量0.06g,m壳聚糖∶m镁盐=1∶1,搅拌15min,静置15min,离心20min,脱色率可达到94.56%;模拟印染废水的pH值是吸附过程中的主要影响因素。     

羧甲基壳聚糖降尘剂的制备及性能研究

以氯乙酸改性壳聚糖制备羧甲基壳聚糖(CMCS)降尘剂的最佳反应条件为m(壳聚糖)/m(NaOH)=1.0,m(氯乙酸)/m(壳聚糖)=1.25,50℃下反应7h;用IR、XRD表征了CMCS;CMCS投加量0.8g/L,在pH值为3.5、温度21℃时,对于煤尘的去除率高达95.3%,且具有低残留、易降解、无污染等独特优点,在降尘领域中有着良好的应用前景。     

PNIPAAm/CMC半互穿网络水凝胶的合成及性质

以N-马来酰化壳聚糖为交联剂,N-异丙基丙烯酰胺(NIPAAm)为单体,羧甲基纤维素钠(CMC)为半互穿材料,在水溶液中通过自由基聚合制备了PNIPAAm/CMC半互穿网络水凝胶.所合成的水凝胶的低临界溶解温度(LCST)在33℃左右,CMC的加入对水凝胶的LCST无显著影响,但随着CMC用量的增加,水凝胶的温度敏感性...     

复合絮凝剂PAC-CTS处理废水中的Cr(Ⅵ)

采用自制的复合絮凝剂聚合氯化铝-壳聚糖(PAC-CTS),在不同实验条件(Cr6+初始浓度及药剂投入量、T、t)下,以PAC-CTS(B=2.0,C=1/10,η=800mpa.s)对Cr6+拟废水做去除试验。最后得出处理含Cr6+六价铬废水的最佳条件:复合絮凝剂PAC-CTS在pH=8,初始Cr6+浓度50mg/L,投入量为120mg/L,室温反应90min的条件下,其Cr6+去除率可达到95%以上。     

壳聚糖复合树脂对铜的吸附研究

本文以壳聚糖为原料,交联海藻酸钠,制得壳聚糖复合树脂,研究其对Cu~(2+)的吸附性能。结果表明,Cu~(2+)初始浓度为200mg/L,投加量为0.05g,吸附平衡时间为3.0h,pH为5.0,吸附效率可达100.6mg/g。壳聚糖复合树脂可用于水体中Cu~(2+)的富集和分离。     

壳聚糖插层高岭土吸附处理电镀废水中的重金属离子

利用壳聚糖插层天然高岭土制备复合吸附剂去除电镀废水中重金属离子的相关研究不多。将天然高岭土活化处理后置于经乙酸溶解的壳聚糖溶胶中,制得壳聚糖插层高岭土复合吸附剂;优化了复合吸附剂的制备条件,考察了pH值、吸附时间以及复合吸附剂的投加量对电镀废水中Cr~(6+)、Ni~(2+)、Cd~(2+)、Pb~(2+)4种重金属离子吸附效果的影响;确定了复合吸附剂的最优制备条件:高岭土预处理温度为700℃,壳聚糖与高岭土的质量比为1∶5。电镀废水中重金属离子最佳脱除条件:pH值为5.0~6.0,吸附时间为60min,投加量为6.0g/L。常温下Cr、Ni、Cd、Pb4种重金属的去除率分别为94.76%、98.58%、92.47%、99.30%。连续5次吸附-解吸循环结果表明,插层复合吸附剂的去除率均大于90%,适用于去除电镀废水中的重金属离子。     

Cu/MgAlO活化过硫酸氢盐降解橙黄Ⅱ

采用浸渍-煅烧法制备Cu/MgAlO,利用扫描电镜、傅里叶红外光谱仪、比表面积测定仪、X射线衍射仪对其进行表征,并用Cu/MgAlO催化过硫酸氢盐(PMS)对橙黄Ⅱ进行催化降解,探索橙黄Ⅱ浓度、Cu/MgAlO投加量、PMS投加量、溶液初始pH、温度、常见离子和水质条件的影响.结果 表明:当溶液初始pH为7,温度为25...     

污泥基生物炭负载纳米零价铁去除Cr(Ⅵ)的性能与机制

针对电镀、冶金、印染等行业产生的含铬废水所导致的环境污染难题,以城市污泥热解获得的污泥基生物炭(SB)为载体,制备了污泥基生物炭负载纳米零价铁(nZVI-SB)材料用于去除水中的Cr(Ⅵ),探究了铁炭质量比、初始pH值、投加量、温度等因素对去除Cr(Ⅵ)的影响。通过SEM-EDS、XRD和XPS等手段对n ZVI-SB去除Cr(Ⅵ)的机制进行分析。结果表明：n ZVI-SB对Cr(Ⅵ)废水具有较好的去除能力。在投加量0.5 g/L、初始pH=2、温度40℃条件下,Fe与SB质量比为1∶1的nZVI-SB(1∶1)对Cr(Ⅵ)吸附量最大为150.60 mg/g。Cr(Ⅵ)去除过程可通过Langmuir吸附等温式与准二级动力学方程进行拟合。nZVI-SB对Cr(Ⅵ)去除机制主要包括吸附、还原和共沉淀。本文表明污泥基生物炭与纳米零价铁可以协同发挥除Cr(Ⅵ)作用。     

微波法制备羧甲基壳聚糖及其在水处理中的应用

采用微波辐射技术、多次醚化工艺改性壳聚糖,合成了水溶性良好的羧甲基壳聚糖。讨论了原水pH值、产品用量对其絮凝性能及产品用量对其脱色性能的影响。结果表明,微波法合成羧甲基壳聚糖工艺简单,大大缩短了反应时间,产物具有良好的絮凝和脱色效果。     

Improvement of dewatering capacity of a petrochemical sludge

Oily sludge produced from a petrochemical industry was used to investigate the improvement of its dewatering properties. The oil content (OC) and the dry solid content (DS) of the raw sludge were respectively, 15% and 3.6% by weight. The capillary suction time (CST) and the specific resistance to filtration (SRF) of the raw petrochemical industrial sludge were found to be 2000s and approximately 5.5x10(16)m/kg, respectively. Conventional chemical conditioners such as alum, lime, and polyelectrolyte, and less conventional ones like fly ash, gypsum, and bentonite were used in the sludge conditioning studies. Conventional chemical conditioners gave better results for the enhancement of the dewatering capacity of the sludge. The best result was obtained by using 0.9% cationic polyelectrolyte by weight, and a decrease of 99%-95% were achieved for CST and SRF, respectively, when this dosage of cationic polyelectrolyte was used.     

Al(Ⅲ)改性胶原蛋白絮凝材料的结构表征及对废弃钻井液絮凝的研究

利用鞣制化学中铝鞣机理,将Al(Ⅲ)络合在明胶水解得到的胶原蛋白分子上,制备Al(Ⅲ)改性胶原蛋白絮凝材料,利用XRD、荧光光谱和XPS对产物结构及作用机理进行表征与分析。将所制备的絮凝剂用于油田废弃钻井液的絮凝,以其CODCr去除率和悬浮物含量为指标,考察了絮凝条件对废弃钻井液处理效果的影响。结果表明胶原蛋白分子与Al(Ⅲ)间发生了配位反应,制备出了Al(Ⅲ)改性胶原蛋白絮凝剂。其用于废弃钻井液絮凝时,用量为20.7g/L,pH值为6～9,温度为20～40℃。絮凝后,废弃钻井液CODCr去除率达80.1%,悬浮物含量从初始的2115mg/L降至190mg/L,絮凝效果明显。     

Alkaline thermal sludge hydrolysis

The waste activated sludge (WAS) treatment of wastewater produces excess sludge which needs further treatment prior to disposal or incineration. A reduction in the amount of excess sludge produced, and the increased dewaterability of the sludge are, therefore, subject of renewed attention and research. A lot of research covers the nature of the sludge solids and associated water. An improved dewaterability requires the disruption of the sludge cell structure. Previous investigations are reviewed in the paper. Thermal hydrolysis is recognized as having the best potential to meet the objectives and acid thermal hydrolysis is most frequently used, despite its serious drawbacks (corrosion, required post-neutralization, solubilization of heavy metals and phosphates, etc.). Alkaline thermal hydrolysis has been studied to a lesser extent, and is the subject of the detailed laboratory-scale research reported in this paper. After assessing the effect of monovalent/divalent cations (respectively, K(+)/Na(+) and Ca(2+)/Mg(2+)) on the sludge dewaterability, only the use of Ca(2+) appears to offer the best solution. The lesser effects of K(+), Na(+) and Mg(2+) confirm previous experimental findings.As a result of the experimental investigations, it can be concluded that alkaline thermal hydrolysis using Ca(OH)(2) is efficient in reducing the residual sludge amounts and in improving the dewaterability. The objectives are fully met at a temperature of 100 degrees C; at a pH approximately 10 and for a 60-min reaction time, where all pathogens are moreover killed. Under these optimum conditions, the rate of mechanical dewatering increases (the capillary suction time (CST) value is decreased from approximately 34s for the initial untreated sample to approximately 22s for the hydrolyzed sludge sample) and the amount of DS to be dewatered is reduced to approximately 60% of the initial untreated amount. The DS-content of the dewatered cake will be increased from 28 (untreated) to 46%.Finally, the mass and energy balances of a wastewater treatment plant with/without advanced sludge treatment (AST) are compared. The data clearly illustrate the benefits of using an alkaline AST-step in the system.     

Preparation of H-oleoyl-carboxymethyl-chitosan and the function as a coagulation agent for residual oil in aqueous system

In this study, H-form oleoyl-carboxymethyl-chitosan (H-O-CMCS) was prepared as a coagulation agent to clean up the residual oil from the waste-water of oil extraction (WWOE). The Fourier transform infrared (FTIR) spectra confirmed the formation of an amide linkage between amino groups of carboxymethyl chitosan (CMCS) and carboxyl groups of oleic acid. The adsorption capacities of four absorbents (H-O-CMCS, chitosan, activated carbon and polyaluminium chloride (PAC)) for the residual oil were investigated. Compared with chitosan, activated carbon and PAC, H-O-CMCS was more effective in removing the residual oil from WWOE, which could successfully wash up almost 99% of residual oil from WWOE at the dosage of 0.2 g/L, the mixing time of 3 min, 500 rpm, and a broader range of pH (the system temperature ≤45°C). In similar conditions, comparatively, chitosan, activated carbon and PAC could wash 90%, 82% and 92% of residual oil from WWOE, respectively.     

Preparation of H-oleoyl-carboxymethyl-chitosan and the function as a coagulation agent for residual oil in aqueous system

In this study, H-form oleoyl-carboxymethyl-chitosan (H-O-CMCS) was prepared as a coagulation agent to clean up the residual oil from the waste-water of oil extraction (WWOE). The Fourier transform infrared (FTIR) spectra confirmed the formation of an amide linkage between amino groups of carboxymethyl chitosan (CMCS) and carboxyl groups of oleic acid. The adsorption capacities of four absorbents (H-O-CMCS, chitosan, activated carbon and polyaluminium chloride (PAC)) for the residual oil were investigated. Compared with chitosan, activated carbon and PAC, H-O-CMCS was more effective in removing the residual oil from WWOE, which could successfully wash up almost 99% of residual oil from WWOE at the dosage of 0.2 g/L, the mixing time of 3 min, 500 rpm, and a broader range of pH (the system temperature ⩽ 45°C). In similar conditions, comparatively, chitosan, activated carbon and PAC could wash 90%, 82% and 92% of residual oil from WWOE, respectively.     

肉桂精油微囊化及其在果蔬保鲜中的应用

目的以壳聚糖、海藻酸钠为壁材,以肉桂精油为芯材,采用复凝聚法制备壳聚糖微胶囊,并将其应用于水果保鲜中。方法通过光学显微镜、扫描电子显微镜、傅里叶转化红外光谱等,确定微胶囊的最佳工艺参数、芯壁比及添加质量分数,并以芒果为实验对象,研究添加不同微胶囊质量分数的壳聚糖溶液对芒果保鲜效果的影响。结果当壳聚糖/海藻酸钠质量比为1∶2,氯化钙质量分数为1%,p H值为5,戊二醛质量分数为60%,交联时间为60 min,芯壁比为4∶1时,制备形成的壳聚糖微胶囊成球效果较好;微胶囊在壳聚糖溶液中的添加质量分数为4%时,以其涂膜的芒果保鲜效果最佳。结论肉桂精油经囊化后有效减少了气味、延缓了挥发,在果蔬保鲜中有较重要的现实研究意义。     

Preparation and flocculation properties of cationic starch/chitosan crosslinking-copolymer

A novel flocculant (CATCS) based on corn starch and chitosan was prepared and its flocculation behaviors were studied. The synthesis conditions of CATCS were discussed and the production obtained was characterized using Fourier infrared spectra and scanning electron microscopy. Flocculation properties of the products were evaluated in terms of transmittance, removal of organic contaminant and solid suspending substances. Influences of temperature, pH and flocculant dosage on flocculation efficiency of CATCS were examined. CATCS had better flocculation performance at lower temperature for the wastewater investigated. CATCS showed better flocculation performance than cationic starch and chitosan in 5 g/L kaolin suspension trended to performance well in acidic and alkaline solution. The comparison of the flocculation performance between CATCS, Fe₂ (SO₄)₃ and polyacrylamide showed CATCS had much efficient flocculation performance. In addition, cationic starch was prepared from corn starch using microwave-assisted method.     

The resistance characteristic of the polymer carbon microcoil composite with temperature change

ABSTRACT

Novel polymer carbon microcoil (CMC) composite has been fabricated by the intercalation of polymer material into free volume contained in CMC sheets grown by chemical vapour deposition process. Then the resistance of composite was measured in two-probe method. It was observed that the resistances of the composite have good reversibility as the temperature cyclic changing near the room temperature; in addition, the intercalation of the organic polymers such as polyvinyl alcohol can improve the resistance sensitivity. We propose that the resistance change is dominantly determined by the contact junctions of CMCs in the composite, which gives a reasonable explanation to the reversibility. The study will be used for sensor research.     

聚乳酸/壳聚糖复合材料的制备及性能研究

目的 以聚乳酸 （PLA） 为基材,与壳聚糖 （CTS） 相结合制备抗菌复合材料。方法 通过熔融挤出复合工艺制备全生物降解抗菌复合材料, 考察壳聚糖对复合材料力学性能和抗菌性能的影响。结果 复合材料的拉伸强度和弯曲强度随着壳聚糖质量分数的增加而略有降低的趋势, 其缺口抗冲击强度基本不受壳聚糖的影响, 断裂伸长率则呈现先上升后减小的趋势。当壳聚糖质量分数为4%时, 复合材料具有较佳的综合力学性能。当壳聚糖的质量分数为8%时, 复合材料具有较明显的抗菌能力。结论 全生物降解聚乳酸壳聚糖复合材料具有广阔的应用前景, 尚需要继续深入探讨两者之间的关系,以制备性能更加优良的全生物降解型材料。