木质素基聚合物的制备及亚甲基蓝的吸附

以木质素磺酸钠为原料单体、环氧氯丙烷为交联剂,采用反相乳液聚合法制备了木质素磺酸钠交联聚合物(SLCP),并将其用于水中有机染料的吸附。表征结果显示:SLCP基本保留了木质素磺酸钠的骨架和官能团,具有良好的热稳定性。实验结果表明:SLCP对亚甲基蓝(MB)有较好的吸附选择性,在加入量为0.5 g/L时就有较高的吸附效率;在溶液p H2~6范围内吸附量随溶液p H增大而迅速提高,溶液p H6后吸附量趋于稳定;最佳吸附温度为35℃;在SLCP加入量0.5 g/L、溶液p H 6.5、吸附温度25℃、初始MB质量浓度100.5 mg/L的条件下,吸附150 min基本可达平衡,吸附平衡时的吸附量和MB去除率分别为191.2 mg/g和95.1%;SLCP对MB的吸附符合Langmuir等温吸附模型,吸附动力学符合Lagergren拟二级动力学方程。     

聚丙烯酰-6-氨基吡啶的制备及其对重金属离子的吸附

以2，6-二氨基吡啶为原料，合成了功能单体2-丙烯酰-6-氨基吡啶，并将其与乙二醇二甲基丙烯酸酯共聚合成了聚合物吸附剂聚丙烯酰-6-氨基吡啶。考察了聚合物吸附剂对重金属离子的吸附分离性能。实验结果表明：在混合液中Cu²⁺，Zn²⁺，Cd²⁺，Ni²⁺的初始质量浓度均为10 mg/L、聚合物吸附剂加入量为5 g/L、溶液pH=7、吸附时间为10 min的条件下，聚合物吸附剂对各离子的吸附率均大于90%；采用浓度为0.5 mol/L的HCl溶液对吸附后的聚合物吸附剂进行洗脱，4种重金属离子的洗脱率均可达97%以上；该吸附剂具有很好的稳定性，重复使用11次后其对4种重金属离子的饱和吸附量均未有明显的下降。     

丙烯酰胺接枝木薯淀粉的合成及橡胶废水的絮凝处理

以丙烯酰胺为单体,过硫酸铵为引发剂,十二烷基磺酸钠为乳化剂,采用乳液聚合法合成丙烯酰胺接枝木薯淀粉(接枝淀粉)。实验结果表明:当m(淀粉)∶m(单体)为1.0∶1.5、合成温度为60℃、引发剂加入量(质量分数)为2.4%时,单体转化率、接枝率和接枝效率分别为74.7%,69.8%,74.9%;当接枝淀粉的加入量为0.35g/L时,絮凝处理后橡胶废水的吸光度由0.164降为0.073,脱色率为55.5%。     

Cu^2＋改性活性炭的制备及其去除废水中CN^-的研究

以活性炭为载体负载溶液中的Cu^2＋，Cu^2＋改性活性炭对溶液中CN^-的去除效果较好。cu。’改性活性炭的最佳制备条件：活性炭加入量为1g，质量浓度为5∥L的CuSO。溶液加入量为50mL，溶液pH为4，负载时间为5．0h.在此最佳条件下活性炭的最大Cu^2＋负载量为25．90mg（以每克活性炭计）。Cu^2＋改性后活性炭的CN^-去除率明显提高，由22．10％提高至94．07％。Cu^2＋改性活性炭吸附CN^-的最佳实验条件：溶液pH为12～13，吸附时间为9h。Cu^2＋改性活性炭对CN^-的饱和吸附量为22mg／g。Mg^2＋，K^＋，Ca^2＋，Cl^-，SO4^2-，CO3^2-，AsO3^-对Cu^2＋改性活性炭的CN^-去除率基本没有影响。Cu^2＋改性活性炭的动态吸附实验表明，开始一段时间流出液中CN^-含量几乎为零，远低于国家排放标准（0．5mg／L）。     

污泥活性炭的制备及其对溶液中Cr6+的吸附

以城市污水厂剩余污泥为原料，采用ZnCl2作活化剂，热解制备污泥活性炭。实验结果表明，制备污泥活性炭的最佳条件热解温度为550℃，ZnCl2溶液浓度为3mol／L，ZnCl2溶液体积与污泥质量比（mL／g）为2．5：1，热解时间为25min。用所制备的污泥活性炭吸附溶液中的Cr6＋最佳吸附条件为：吸附时间90min，Cr6＋初始质量浓度50mg／L，污泥活性炭加入量0．2g，溶液pH2，在此条件下，Cr6＋去除率达99．9％。污泥活性炭对溶液中Cr6＋的吸附等温线属于I型，等温吸附方程可用Langmuir模型和Freundlich模型来拟合。     

聚丙烯酰-6-氨基吡啶的制备及其对重金属离子的吸附

以2,6-二氨基吡啶为原料,合成了功能单体2-丙烯酰-6-氨基吡啶,并将其与乙二醇二甲基丙烯酸酯共聚合成了聚合物吸附剂聚丙烯酰-6-氨基吡啶。考察了聚合物吸附剂对重金属离子的吸附分离性能。实验结果表明:在混合液中Cu2+,Zn2+,Cd2+,Ni2+的初始质量浓度均为10 mg/L、聚合物吸附剂加入量为5 g/L、溶液pH=7、吸附时间为10 min的条件下,聚合物吸附剂对各离子的吸附率均大于90%;采用浓度为0.5 mol/L的HCl溶液对吸附后的聚合物吸附剂进行洗脱,4种重金属离子的洗脱率均可达97%以上;该吸附剂具有很好的稳定性,重复使用11次后其对4种重金属离子的饱和吸附量均未有明显的下降。     

已二酸生产副产物——混合二元酸的综合利用

采用一水合硫酸氢钠作为催化剂，催化己二酸生产副产物——混合二元酸与甲醇反应合成混合二元酸二甲酯。优化工艺条件为：混合二元酸加入量0．1mol，无水甲醇加入量0．5mol，一水合硫酸氢钠加入量4．0g，环己烷加入量20mL，反应时间1．5h。合成混合二元酸二甲酯的酯化反应收率大于97％。经气相色谱检测，产物中酯的质量分数为98．91％。一水合硫酸氢钠可重复使用3次。     

混凝-催化氧化法预处理氨基C酸生产废水

采用混凝-催化氧化组合工艺预处理氨基C酸生产废水，考察了混凝剂加入量、废水pH、氧化剂加入量、反应时间和催化剂的重复使用次数等因素对废水处理效果的影响。混凝-催化氧化法预处理氨基C酸生产废水的最佳工艺条件为：质量分数为10％的FeSO4溶液作混凝剂，加入量为250InL／L；质量分数为1％的ClO2溶液作氧化剂，加入量为75mL／L；Ni／AC作催化剂，加入量为40g/L；废水pH为3．2；催化氧化反应时间为60min。在该条件下，废水的COD去除率可达78．4％，BOD，／COD由原来的0．076提高到0．292，可生化性得到明显改善。Ni／AC催化剂连续使用7次后仍保持稳定的催化活性。经济性初步分析表明，1t废水的处理成本约为16元。     

Cu2+-Mn2+-H2O2体系催化氧化降解罗丹明B

研究了Cu2＋-Mn2＋-H2O2体系催化氧化降解染料罗丹明B的效果。实验结果表明，Cu2＋-Mn2＋-H2O2体系的罗丹明B降解率比H2O2体系、Mn2＋-H2O2体系和Cu2＋-H2O2体系有显著提高，反应120rain后罗丹明B降解率接近100％。对于Cu2＋-Mn2＋-H2O2体系，最佳罗丹明B降解条件：溶液pH为5，反应温度为45℃，质量浓度为10mg／L的罗丹明B溶液体积100mL，浓度为0．01mol／L的硫酸铜溶液加入量5．0mL，浓度为0．01moVL的硫酸锰溶液加入量3．0mL，体积分数为30％的H2O2溶液加入量1．5mL。在此条件下罗丹明B降解的反应速率常数最大，为0．04228min-1，其拟合相关系数为0．99912。罗丹明B降解符合一级动力学模型。     

微波-改性活性炭-Fenton试剂氧化法降解水中2,4-二氯酚

以经Fe2（SO4）3溶液浸渍改性的活性炭作催化剂、Fenton试剂作氧化剂，采用微波-改性活性炭-Fenton试剂氧化法降解水中的2，4-二氯酚。考察了改性活性炭加入量、H2O2与Fe^2＋摩尔比、Fenton试剂加入量、微波功率和2，4-二氯酚溶液初始pH对2，4-二氯酚降解效果的影响。在改性活性炭加入量1．0g／L、n（H2O2）：n（Fe^2＋）=16．7（H2O2加入量6．0mmol／L、Fe^2＋加入量0．36mmol／L）、Fenton试剂加入量为6．36mmol／L、微波功率600W、微波辐射时间10min、2，4-二氯酚溶液初始pH为6．0的条件下，2，4-二氯酚降解率和TOC去除率分别可达98．7％和84．0％。     

Review of the kinetics of alkaline degradation of cellulose in view of its relevance for safety assessment of radioactive waste repositories

The degradation of cellulose (a substantial component of low- and intermediate-level radioactive waste) under alkaline conditions occurs via two main processes: a peeling-off reaction and a basecatalyzed cleavage of glycosidic bonds (hydrolysis). Both processes show pseudo-first-order kinetics. At ambient temperature, the peeling-off process is the dominant degradation mechanism, resulting in the formation of mainly isosaccharinic acid. The degradation depends strongly on the degree of polymerization (DP) and on the number of reducing end groups present in cellulose. Beyond pH 12.5, the OH^- concentration has only a minor effect on the degradation rate. It was estimated that under repository conditions (alkaline environment, pH 13.3-12.5) about 10% of the cellulosic materials (average DP = 1000-2000) will degrade in the first stage (up to 10⁵ years) by the peeling-off reaction and will cause an ingrowth of isosaccharinic acid in the interstitial cement pore water. In the second stage (10⁵-10⁶ years), alkaline hydrolysis will control the further degradation of the cellulose. The potential role of microorganisms in the degradation of cellulose under alkaline conditions could not be evaluated. Proper assessment of the effect of cellulose degradation on the mobilization of radionuclides basically requires knowing the concentration of isosaccharinic acid in the pore water. This concentration, however, depends on several factors such as the stability of ISA under alkaline conditions, sorption of ISA on cement, formation of sparingly soluble ISA-salts, etc. A discussion of all the relevant processes involved, however, is far beyond the scope of the presented overview.     

Study of Aging Characteristics of Ternary Blends of Polyethylenes—II

Six film samples of low-density polypropylene (LDPE)/linear LDPE (LLDPE)/high-density polypropylene (HDPE) with varying ratios of LDPE (20–45 ... wt%) and LLDPE (25–50 wt%) having a fixed amount of HDPE at 30 wt% were prepared by blown film extrusion technique. The samples were aged at four different temperatures, 55°, 70°, 85°, and 100°C, for four different time periods in the interval of between 150 hours and up to 600 hours. The change in the structure of various constituents and the formation of various oxygenated (peroxy and hydroperoxy) and unsaturated groups during thermo-oxidative degradation was discussed by infrared spectroscopy. The visiosity-average molecular weight was found to have decreased slowly in the initial aging hours and temperatures, whereas it decreased by 10% with its previous value tensile strength that is, 100°C when aged for 600 hours. The tensile strength of the sample first increased by 67% at 55°C and 89% at 70°C up to 450 hours, whereas the values increased by 52.5% at 85°C and 33.9% at 100°C when aged for 150 hours and then decreased. The percentage elongation at break increased by 2.7% at 55°C and 10.7% at 70°C for 150 and 300 hours of aging, respectively, whereas the percentage decreased when aged at 85°C and 100°C for up to 600 hours of aging. The values of gel content (percent) increased and initial degradation temperature decreased with aging time and temperature.     

Calculation of carbon balances for evaluation of the biodegradability of polymers

Establishing carbon balances has been proven to be an applicable and powerful tool in testing biodegradability of polymers. In controlled degradation tests at a 4-L scale with the model polymer poly(-hydroxybutyrate) (PHB), it was shown that the degree of degradation could not be determined with satisfactory accuracy from CO₂ release alone. Instead, the course of degradation was characterized by means of establishing carbon balances for the degradation of PHB withAcidovorax facilis and a mixed culture derived from compost. Different analytical methods for determining the different carbon fractions were adapted to the particular test conditions and compared. Quantitative determination of biomass and residual polymer were the main problems in establishing carbon balances. Amounts of biomass derived from protein measurements depend strongly on assumptions of the protein content of the biomass. Selective oxidation of biomass with hypochlorite was used as alternative, but here problems arose from insoluble metabolic products. Determination of soluble components with the method of chemical oxygen demand (COD) also includes empirical assumptions but seems acceptable if the dissolved carbon fraction is in the range of some 10% total carbon. Results confirm both analytical assays and theoretical approaches, in ending up at values very close to 100%, within an acceptable standard deviation range under test conditions comparable to standard test practice.Paper presented at the Bio/Environmentally Degradable Polymer Society—Third National Meeting, June 6–8, 1994, Boston, Massachusetts.     

Model of technological alternatives of production of sodium chromate (VI) with the use of chromic wastes

This article presents a mathematical model which describes the sodium chromate (VI) production process with the use of chromic waste as a substitution of natural raw materials. This model is a function of selected process parameters common for all of the examined alternatives and based on equations of material balance. Optimization of the elaborated technological alternatives of the production process with use of recycling of chromic waste has been evaluated by determining the extreme value of the quality indicator WJ. This indicator defines the quantity of waste created in the process. Optimization results enabled the selection of the optimal technological solution from all of the alternatives possible for use in industrial practice. Negative values of the indicator prove that there is the possibility of introducing to the process a larger quantity of waste than the one obtained in the process and transported to the storage heaps.     

化学品生物降解性的评价与预测

介绍了有机化学物质生物降解性的测定方法及其预测方法研究概况，并讨论了生物降解性评价的发展前景。     

Determination of the Burning Characteristics of a Slick of Oil on Water

The burning rate of a slick of oil on a water bed is characterized by three distinct processes, ignition, flame spread and burning rate. Although all three processes are important, ignition and burning rate are critical. The former, because it defines the potential to burn and the latter because of the inherent possibility of boilover. Burning rate is calculated by a simple expression derived from a one-dimensional heat conduction equation. Heat feedback from the flame to the surface is assumed to be a constant fraction of the total energy released by the combustion reaction. The constant fraction (χ) is named the burning efficiency and represents an important tool in assessing the potential of in situ burning as a counter-measure to an oil spill. By matching the characteristic thermal penetration length scale for the fuel/water system and an equivalent single layer system, a combined thermal diffusivity can be calculated and used to obtain an analytical solution for the burning rate. Theoretical expressions were correlated with crude oil and heating oil, for a number of pool diameters and initial fuel layer thickness. Experiments were also conducted with emulsified and weathered crude oil. The simple analytical expression describes well the effects of pool diameter and initial fuel layer thickness permitting a better observation of the effects of weathering, emulsification and net heat feedback to the fuel surface. Experiments showed that only a small fraction of the heat released by the flame is retained by the fuel layer and water bed (of the order of 1%). Ignition has been studied to provide a tool that will serve to assess a fuels ease to ignite under conditions that are representative of oil spills. Two different techniques are used, piloted ignition when the fuel is exposed to a radiant heat flux and flash point as measured by the ASTM D56 Tag Closed Cup Test. Two different crude oils were used for these experiments, ANS and Cook Inlet. Crude oils were tested in their natural state and at different levels of weathering, showing that piloted ignition and flash point are strong functions of weathering level.     

Mechanism of Microbial Degradation of Slow-Release Fertilizers

Methyleneureas are condensation products of urea and formaldehyde of different molecular mass and solubility; they are used in large amounts both as resins, binders, and insulating materials for industrial applications, as well as a slow-release nitrogen fertilizer for greens, lawns, or in bioremediation processes. In the present study, the microbial breakdown of these products was investigated. The nitrogen was released as ammonia and urea, and the formaldehyde released immediately oxidized via formiate to carbon dioxide. The enzymatic mechanism of metabolization of methyleneureas was studied in microorganisms isolated from soil, which were able to use these compounds as the sole source of nitrogen for growth. A strain of the Gram-negative bacterium Ralstonia paucula (formerly Alcaligenes sp. CDC group IVc-2) completely degraded methylenediurea and dimethylenetriurea to urea, ammonia, formaldehyde, and carbon dioxide. The enzyme initiating this degradation (methylenediurease) was purified and turned out to be different from the previously described enzyme from Ochrobactrum anthropi with regard to its regulation of expression and physicobiochemical properties. Fungal degradation of methyleneureas may occur via the formation of organic acids, thus leading to a nonenzymatic degradation of methyleneureas, which are unstable under acidic conditions.     

Effect of Degree of Substitution of Octenyl Succinate Starch on Enzymatic Degradation

Octenyl succinate starch of degree of substitution (ds) 0.03, 0.07, and 0.11 was synthesized in an aqueous medium. These compounds were then tested for the susceptibility to enzymatic degradation. The multiple-enzyme regime of -amylase, amyloglucosidase, and pullulanase was chosen for the evaluation. This combination of enzymes had been proven to degrade 99.5% of unmodified starch to glucose and hence was chosen for this study. It was found that even small amounts of subsituent caused a considerable decrease in the extent of degradation. The net extent of degradation decreased with increasing ds. Surprisingly, the amount of glucose from all three substituted substrates was quite similar, suggesting the effect small amounts of subtituent had on the enzymatic activity.     

Electron Microscope Observation of Biodegradation of Polymers

Biodegradable polymers generally decompose in the various media in our environments. These environments contain soils, seawater, and activated sludge. If biodegradable materials waste is discarded, they decompose in these media. The biodegradation process of biodegradable polymers was investigated by scanning electron microscopy. Polycaprolactone, polybutylene succinate, and P(3HB-co-3HV) were tested. The shapes of holes on the decomposing surfaces are different according to the biodegradation media. Semispherical holes are observed on the surfaces of polybutylene succinate films degraded in activated sludge and cracks are observed on the surfaces of polycaprolactone films degraded in soil.     

Structure-biodegradation relationships of polymeric materials. 1. Effect of degree of oxidation on biodegradability of carbohydrate polymers

The biodegradability of oxidized starch and inulin has been studied in relation to the degree of periodate oxidation to dialdehyde derivatives, by measuring oxygen consumption and mineralization to carbon dioxide. A higher degree of oxidation of dialdehyde starch and dialdchyde inulin results in a lower rate at which the polymers are biodegraded. It is demonstrated that the biodegradation rate of dialdehyde inulin derivatives decreases more than that of equivalent starch derivatives. The differences in biodegradation behavior between dialdehyde starch and dialdehyde inulin, resulting from comparable modifications, are discussed in terms of conformational structure.