丝光沸石水蒸气/酸浸渍脱铝的多核固体核磁共振研究

采用 1 H,2 9Si,2 7Al魔角旋转固体核磁共振 ( MAS NMR)及 1 H-2 9Si交叉极化 ( CP)技术研究丝光沸石水蒸气 /酸浸渍脱铝过程中各种铝物质的结构与性质 .结果表明 ,丝光沸石上骨架铝原子在水分子作用下 ,生成非骨架四配位铝物质 [Al( OH) 3( H2 O) ],分别在 2 7Al谱 δ45和 1 H谱 δ3 .0处出现共振信号 ,这种铝物质不同于扭曲四配位铝 ,在高温下进一步水合生成 Al( OH) 3( H2 O) 2 和 Al( OH) 3( H2 O) 3,即非骨架五配位和六配位铝物质 .1 H-2 9Si CP和1 H谱证实 ,水蒸气脱铝使丝光沸石产生了大量的硅羟基和铝羟基 .

稀酸浸渍气爆预处理对纤维素乙醇同步糖化发酵的影响

纤维素乙醇预处理过程效率偏低是影响纤维素乙醇发展的一个重要因素。通过改进传统蒸汽爆破预处理方法,在蒸汽爆破前加入稀酸浸渍,有效地提高了后续同步糖化发酵的水平。采用硫酸浸渍气爆预处理后的草浆同步糖化发酵乙醇质量浓度达到27.5 g/L,达到葡萄糖乙醇理论产率的81%;采用乙酸浸渍气爆预处理后的草浆同步糖化发酵乙醇质量浓度达到25.5 g/L,达到葡萄糖乙醇理论产率的77%;相比传统气爆草浆用于同步糖化发酵,稀酸预处理能有效地减少抑制物的生成,提高后续直接利用草浆进行同步糖化发酵的水平,从而提高生产效率,降低生产成本,是可应用于工业化纤维素乙醇生产的重要方法。

用副产酸浸渍骨料的效果

目前国内合成盐酸的价格多在600元/吨。骨明胶生产厂家是用酸大户,每生产一吨骨明胶就需耗用9～10吨工业盐酸,每吨骨明胶的生产成本中盐酸就占了5000～6000元,盐酸费用占了明胶生产成本的1/3～1/4。为了降低成本,提高经济效益,采用氯乙酸生产中得到的副产酸浸渍骨料,可能是一条较可行的捷径。

改性分子筛催化和酸处理对玉米秸秆热解油组分的影响

为进一步提高生物油的品质,探究盐酸预处理及Mo改性HZSM-5催化剂对热解产物生物油组分分布的影响规律,以玉米秸秆为原料,采用等体积浸渍法制备Mo/HZSM-5催化剂,并用XRD、SEM、FTIR对催化剂进行表征分析,利用Py-GC/MS装置对热解生物油的组分进行分析。结果表明:酸洗和酸浸渍能有效减少生物油中酸类和酮类化合物的含量,生物油中糠醛的相对含量从3.21%分别提高到5.24%和4.46%,并促进生成了新物质D-阿洛糖相对含量分别为3.42%和3.33%。HZSM-5和Mo/HZSM-5的催化作用能显著降低生物油中乙酸的含量,与原生物油相比分别减少8.34%和7.34%,同时提高了糠醛和D-阿洛糖的相对含量。另外,在Mo/HZSM-5作用下产生新物质环己烷相对含量分别为1.14%、1.25%、1.35%,使苯、甲苯和二甲苯(BTX)的相对含量进一步提高。酸浸渍和Mo/HZSM-5的共同作用显著降低了生物油中醛类、酮类和酸类等含氧化合物含量,使芳烃类化合的相对含量达到最大值,有效改善了生物油的品质,为玉米秸秆的高质化利用提供了理论基础。

高温浸渍法PBI／H3PO4复合膜特性及电池性能研究

以国产3,3'-二氨基联苯胺和间苯二甲酸为单体,合成了具有良好溶解性的聚苯并咪唑(PBI)树脂。通过红外和核磁共振表征证实了聚苯并咪唑的结构。溶液浇铸法制备了PBI膜,并利用高温浸渍法制备了PBI/H3PO4复合膜,考察了浸渍温度对膜特性的影响。相对于室温浸泡,高温浸泡磷酸降低了复合膜的初始水含量,有利于提高膜中酸含量,从而提高电池性能。采用PBI作为粘结剂、聚偏氟乙烯(PVDF)作为憎水剂、Pt/C为催化剂制备了催化层,通过优化催化层中各组分配比制备了膜电极,并采用无增湿氢气和氧气对膜电极性能进行了测试,在表压0.2MPa、150℃的条件下,电池最大功率密度达到1.537W/cm2。

晶硅切割废砂浆回收中三级砂的组分分离研究

以晶硅切割废砂浆回收中三级砂为原料,采用化学方法对其组分分离,设计正交实验,研究了液固比、溶液浓度等工艺因素对分离效果的影响,采用XRD和SEM对相组成和微观形貌进行分析,结果表明:采用酸浸渍法除铁,对三级砂的结构和形貌无影响,当液固比为12∶1,盐酸浓度为1.0 mol/L,浸溶温度为50℃,浸溶时间为1 h时,除铁效果最佳。进一步采用碱液滴加法除硅,可以实现三级砂中Si和Si C的有效分离,当液固比为12∶1,氢氧化钠质量浓度为12%,反应温度为70℃时,除硅效果最佳。

Extraction of cerium(Ⅳ) using tributyl phosphate impregnated resin from nitric acid medium

Tributyl phosphate （TBP） solvent was used for impregnation into Amberlite XAD-16 nonionic polymeric resin beads using the wet method to prepare solvent impregnated resin （SIR）. Undiluted TBP in a ratio to the resin support （volume to mass） of 6.0 at room temperature （RT） in 24 h was impregnated the resin with a mass ratio of 1.944, while the prepared gross sample of SIR at the ratio of solvent to resin of 3.0 was impregnated with a mass ratio of 1.88. Cerium（Ⅳ） oxide concentrate, prepared from crude Egyptian monazite sand, containing 37% cerium, 1.6% thorium and about 40% the other trivalent rare earth oxides, was used to prepare cerium（Ⅳ） nitrate solution for extraction using the prepared SIR. The impregnated resin was satisfactory for Ce（Ⅳ） extraction from nitric acid medium at room temperature. Cerium loading capacity of the impregnated resin reached 95.6% of the calculated theoretical capacity （173 g/kg （Ce/SIR）） under the conditions of 51.57 g/L cerium and 2.48 g/L thorium, 5.0 mol/L free nitric acid, solution to resin ratio of 10.0 and contacting the phases for 5.0 min. The loading capacity reached 98.75% when cerium concentration was increased to 91.43 g/L under the same conditions.

Erosion characteristic of slope sandstone soaking in acid mine drainage

Acid mine drainage（AMD） is one of the main reasons of slope instability in chemical mines with high sulfide. The pH values of the solution inside the mining pit decrease with the increasing of distance from ore body and vary from 1.2 to 4.6, according to the results of the water environmental investigation and the composition test of the slope sandstone in Xinqiao Pyrite Mine. Comparative experiments between original sandstone and AMD eroded sandstone samples show that after AMD erosion the uniaxial compressive strength and elastic modulus decrease by 30%-50% and 25%-45%, respectively, the cohesion and internal friction angle decrease obviously, and the Poisson ratio fluctuates between 0.20-0.29. The greater joints development, the higher residual stress after peak value, and the longer time to damage. Besides above, the reaction mechanism analysis of AMD eroded sandstone shows that the fillings in joints and fissures of sandstone are frequently decomposed and polyreacted, resulting in changes of interior molecule structure and fi＇amework composition, and decreases of cohesion and angle of internal friction between rock structure interfaces.

Adsorption of 2-naphthalenesulfonic acid/sulfuric acid/sulfurous acid from aqueous solution by iron-impregnated weakly basic resin：Equilibrium and model

Commercial grade weakly basic resin D301 was impregnated with iron through a simple method using ferric chloride. Experiments for single, bisolute and trinary competitive adsorption were carried out to investigate the adsorption behavior of 2-naphthalenesulfonic acid(NSA), sulfuric acid and sulfurous acid from their solution at 298 K onto the novel hybrid iron impregnated D301(Fe-D301). Adsorption affinity of NSA on Fe-D301 was found to be much higher than that of sulfuric acid, while adsorption affinity of sulfuric acid was slightly higher than that of sulfurous acid. The data of single-solute adsorption were fitted to the Langmuir model and the Freundlich adsorption model. The non-ideal competitive adsorbed model coupled with the single-solute adsorption models were used to predict the bisolute and trinary-solute competitive adsorption equilibria. The NICM coupled with the Langmuir model yields the favorable representation of the bisolute and trinary-solute competitive adsorption behavior.

酸渍平菇工艺研究

研究了用冰乙酸和食盐的混合液作为汤汁的酸渍平菇生产工艺、产品检验等,筛选出了最佳生产工艺条件。可用于食用菌的加工生产,促进了食用菌深加工的多样化发展。

Humic-Like Substances from Different Compost Extracts Could Significantly Promote Cucumber Growth

The effects of direct extracts of compost (DEC), aerated fermentation extracts of compost (AFEC) and non-aerated fermentation extracts of compost (NAFEC) on cucumber growth and the action mechanisms were evaluated based on the structure and activity analysis of humic-like substances. AFEC increased cucumber growth most significantly, followed by DEC and NAFEC, which was insignificant compared to the control treatment. Humic-like substances from compost extracts played an important role in promoting cucumber growth. Application of humic-like substances stimulated auxin-like activity and increased chlorophyll content and nitrogen accumulation in plants. The positive auxin-like activity of humic-like substances could be attributed to the relative distribution of special carbon groups, such as those with a large amount of peptidic and carbohydratic groups or with a low content of phenolic groups. In conclusion, the best growth promotion by application of AFEC was mainly attributed to the humic-like substances in the AFEC.