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《化学研究与应用》2016,(10)
以十六醇、环氧氯丙烷、二甲胺和氯乙酸钠等为原料,通过三步反应合成N-(3-十六烷氧基-2-羟基丙基)-N,N-二甲基甜菜碱(HHDB),并探索了反应温度、投料比、反应时间和催化剂等因素对产物产率的影响,确定了最佳反应条件。中间体3-十六烷氧基-2-羟基-1-氯丙烷(HHCP)合成的最佳工艺条件:催化剂苄基三乙基氯化铵,体系p H为9.0,n(C_(16)H_(33)OH)∶n(C_3H_5OCl)=1∶1.1,滴加环氧氯丙烷温度65℃,滴加时间1.5h,反应温度95℃,反应时间5 h;中间体N-(3-十六烷氧基-2-羟基丙基)-N,N-二甲基叔胺(HHDT)合成的最佳工艺条件:n(C_(19)H_(39)OCl)∶n(C_2H_7N)=1∶1.2,反应温度85℃,反应时间20 h;产物HHDB制备的最佳工艺条件:n(C_(21)H_(45)ON)∶n(C_3H_4O_2ClNa)=1∶1.1,反应温度80℃,反应时间4 h。在上述工艺条件下,HHDB产率达到95.2%,对产物HHDB及中间体进行红外光谱与核磁氢谱表征,测定其临界胶束浓度为9.8 mmol·L-1,水溶液表面张力为18.8 m N·m-1,发泡力为1.15,产物具有较好的表面活性。 相似文献
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采用沉淀-浸渍法制备了不同金属配比的S2O82-/TiO2-Al2O3固体超强酸催化剂,并研究了其在催化水解花生壳制备乙酰丙酸反应中的作用。实验发现n(Al)∶n(Ti)=1∶2时催化效果最佳,并进一步考察了其水解温度,水解时间,固体酸用量和液固比对乙酰丙酸得率的影响。采用响应面法对水解工艺进行了优化,并建立二次回归模型。结果表明,当水解温度为235℃、水解时间为30min、固体酸用量为4.6%和液固比18∶1(mL/g)时为较优的制备工艺,在该工艺条件下,乙酰丙酸得率为26.43%。 相似文献
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先以BaCO3和Bi2O3为原料由传统的固相反应制备纯BaBiO3,然后在低温下将用KOH-KF熔盐处理这样的拓扑反应合成了Ba1-xKxBiO3超导体.所有样品均进行了粉末X射线衍射(XRD)和磁性表征.XRD结果表明,所得Ba1-xKxBiO3样品均为纯相,且均可用赝立方晶胞指标化.磁性测量表明所有样品具有超导电性,最高超导转变温度(Tc)为30.6 K.讨论了反应时间、前驱体与熔盐质量比对超导转变温度的影响.最佳的反应条件为:反应温度450℃,反应时间4h,BaBiO3∶KOH∶KF质量比1∶5∶2.5. 相似文献
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利用液固相水热反应方法, 以硅溶胶为硅源, 在三价铁辅助下与乙二胺的水溶液在180 ℃反应4 d后生成具有P21212空间群结构的单晶氧化硅纳米线. 用扫描电子显微镜、透射电子显微镜和多晶X射线衍射对制备的样品进行了表征, 系统研究了有机胺、金属盐、反应时间及反应温度等条件对氧化硅纳米线生长的影响. 结果表明, 随着有机胺碳链的增长, 产物形貌逐渐由纳米线转变为纳米片; 金属阳离子的存在对纳米线形貌有较大的影响, 而阴离子的存在并不影响纳米线的生成; 过低的铁含量导致反应进行不完全, 而过多的铁盐加入则会导致反应中剩余铁氧化物吸附到氧化硅纳米线表面, 进而影响到产物纯度; 反应时间延长及反应温度的提高都有利于氧化硅纳米线的生长. 最佳反应条件为: 有机胺为乙二胺, 硝酸铁为铁源, 硅溶胶为硅源, 硅/铁摩尔比为1∶0.4, 乙二胺与水的体积比为8∶5, 温度为180 ℃. 相似文献
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UF-两段厌氧处理茶多酚废水的研究 总被引:1,自引:0,他引:1
采用前置超滤膜(UF)的两相厌氧工艺对原水COD为18362.6mg/L,荼多酚为3608.3mg/L、色度为2624.2倍的茶多酚生产废水进行为期90d的实验研究.结果表明,当实验压力为0.2Mpa时,膜组件对COD去除率为63.4%,茶多酚去除率为95.1%,色度去除率为93.4%.然后,对两相厌氧工艺的投配率、P含量和酸化段水力停留时间(HRT1)对废水COD、色度与茶多酚去除率和产气率的影响进行了研究.当投配率为15.0%、P含量为38.1mg/L、HRT1=24h,该工艺达到最佳处理效果,出水COD为1288.1mg/L,COD去除率为80.8%,色度为95.6倍,色度去除率为44.6%,残余茶多酚为119.8mg/L,茶多酚去除率为32.3%,产气率为0.85m3/kg COD,与未采用UF预处理的两相厌氧水解工艺相比,COD、色度和荼多酚去除率分别提高23.40%,10.2%和1613%,产气率增加0.15m3/kg COD. 相似文献
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聚合氯化铁的制备及其絮凝效果 总被引:1,自引:0,他引:1
以赤铁矿和工业盐酸为原料,采用盐酸酸浸和加碱聚合等方法制取聚合氯化铁絮凝剂(PFC),将其用来处理造纸废水,并与市售聚合氯化铁和碱式氯化铝絮凝剂进行比较.结果表明,在碱化度为2∶1、聚合温度为40℃、陈化时间为24h时,自制聚合氯化铁絮凝剂对造纸废水具有较好的处理效果;投加量为1.4mL/L时,造纸废水的浊度降低了99%,化学需氧量(COD)降低了69.55%,优于市售絮凝剂对造纸废水的处理效果;且三种絮凝剂用量相同时,自制的聚合氯化铁絮凝剂形成絮体的速率和沉降速率都较快. 相似文献
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镀铜铁屑-H_2O_2催化氧化降解含酚废水 总被引:2,自引:0,他引:2
采用镀铜铁屑代替传统Fenton体系中的FeSO4作为催化剂,通过改变H2O2与镀铜铁屑的投加量、溶液的pH值、反应温度、反应时间等条件,研究了该体系对处理苯酚废水的影响。结果表明,常温下处理实际含酚印染废水,在pH值为4~6,30%H2O2 12mL/L,镀铜铁屑5g/L,反应时间为45min时,COD去除率可达96%,其CODCr从5827mg/L降至419mg/L,色度从2000降至30,符合国家三级排放标准。 相似文献
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A study using coagulation-flocculation and ultrafiltration (UF)methods for pulp and paper mills’ wastewater (WW)was carried
out. The reduction efficiencies of turbidity and chemical oxygen demand (COD), the removal efficiency of total suspended solids
(TSS) and absorbance at 254 nm were the main evaluating parameters. Using coagulation-flocculation, the efficiencies of alum
and polyaluminum chloride (PACl)were studied, when used alone and when coupled with flocculant aids. During the coagulation-flocculation
process, use of a single coagulant, the coagulant dosage, and the pH, play an important role in determining the coagulation
efficiency. At the optimum PACl dosage of 840 mg L−1 and optimum pH of 9.0, turbidity reduction was found to be 94.5%. A combination of inorganic coagulant and flocculant, or
polymer was applied, in which PACl was used coupled with the polyelectrolytes Organopol WPB20 and WPB40. PACl coupled with
Organopol WPB20 by optimal pH 9 gave a 98.3% reduction of turbidity, 91.9% removal of TSS, and a 60.2% reduction in COD. Ultrafiltration
trials were carried out on a pilot scale. A tubular module was used with ceramic membrane. This membrane is a multi-channel
membrane with an active surface layer made of Al2O3 and ZrO2. Within the acidic range, the turbidity and TSS were removed at above 99%. 相似文献
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以酶解木质素、甲醛、二甲胺及阳离子化试剂为原料,制备了木质素基阳离子絮凝剂.改变阳离子化试剂的用量、缩合反应的温度和时间等因素,制备不同阳离子度的木质素阳离子絮凝剂;通过其对酸性黑10B的脱色效果研究,确定了最优的制备方案.利用最优条件制备的木质素阳离子絮凝剂对三种不同种类阴离子染料废水进行了絮凝脱色处理.结果表明,原... 相似文献
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Study of flocculation with PONILIT GT-2 anionic polyelectrolyte applied into a chemical wastewater treatment 总被引:1,自引:0,他引:1
Carmen Zaharia Rodica Diaconescu Mioara Surpăţeanu 《Central European Journal of Chemistry》2007,5(1):239-256
This paper discusses the applications of synthetic PONILIT GT-2 anionic polyelectrolyte in conjuction with ferric sulfate
in a chemical wastewater treatment viz. wastewater from ceramics manufacturing. Synthetic wastewaters with different colloid
concentrations were prepared and the coagulation-flocculation process followed by sedimentation and/or filtration was studied.
Variables associated with the chemical wastewater composition, mixing time, and the coagulant and flocculant dose are considered
in order to appreciate the process efficiency in terms of turbidity, chemical oxygen demand (COD), and color removal. The
degrees are higher for turbidity and color (> 80 %) removal respectively, and, satisfactory for COD (< 50 %). An empirical
model was elaborated by a third order rotatable design 23 type, considering ferric sulfate dose, polyelectrolyte dose, and mixing time as independent variables, while the turbidity
and color removal efficiencies were chosen as optimization criteria. The empirical model was found adequate for the chemical
wastewater treatment. Also, an analysis of the model was performed to find the optimal operating conditions, in order to apply
this process for an efficient chemical wastewater treatment using ferric sulfate as coagulation agent and PONILIT GT-2 anionic
polyelectrolyte as flocculation agent. The optimal values correspond to a ferric ions concentration of 6.093 mg/L, a polyelectrolyte
dose of 0.651 mg/L, and a mixing time of 24.024 minutes for turbidity removal (95.869 %), respectively, and, to a ferric ions
concentration of 6.01 mg/L, a polyelectrolyte dose of 0.69 mg/L, and a mixing time of 26 minutes for color removal (98.741
%).
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