Adsorption of 2-mercaptobenzothiazole from aqueous solution by organo-bentonite

The adsorption behavior of 2-mercaptobenzothiazole onto organo-bentonite was investigated.Natural bentonite from Gaozhou in Guangdong Province,China was collected.Organo-bentonite was prepared by intercalation of cetyltrimethyl ammonium bromide into the natural bentonite.The physicochemical properties of the prepared organo-bentonite were characterized by X-ray diffraction,N2 adsorption-desorption isotherm and Fourier transform infrared spectroscopy.The results showed that montmorillonite is the main component of the natural bentonite.The basal spacing of the natural bentonite is 1.47 nm,which increased to 1.98 nm on intercalation with cetyltrimethyl ammonium bromide.Moreover,both the surface area and pore volume increased with intercalation.Clear CH2 stretching(3000-2800 cm-1) and scissoring(1480-1450 cm-1) modes of the intercalated surfactants were observed for organobentonite.Compared with the pseudo first-order kinetic model,the pseudo second-order kinetic model is more suitable to describe the adsorption kinetics of 2-mercaptobenzothiazole onto organo-bentonite.The adsorption capacity of 2-mercaptobenzothiazole onto organo-bentonite increased with increasing initial concentration of 2-mercaptobenzothiazole,but decreased with increasing adsorbent dosage.The adsorption isotherm of 2-mercaptobenzothiazole onto organo-bentonite fits well with the Langmuir model.The maximum adsorption capacity of organo-bentonite for 2-mercaptobenzothiazole was 33.61 mg/g,indicating that organo-bentonite is a promising adsorbent for 2-mercaptobenzothiazole.     

Critical velocity in phosphorus exchange processes across the sediment-water interface

Sediments are ultimate sinks of nutrients in lakes that record the pollution history evolutionary processes, and anthropogenic activities of a lake. However, sediments are considered as inner sources of environmental factor changes such as the variation in hydrodynamic conditions because of the nutrients they release. How does this process happen？ This study investigates a typical nutrient phosphorus （P） exchange among sediment, suspended particle matter （SPM）, and water. Compared with numerical and experimental studies, this study confirms that the critical velocity that occurs at a lower flow rate state exists in the range of 7 to 15 crn/sec. Critical velocity below the critical flow rate promotes the migration of particulate phosphorus （PP） to the SPM. On the other hand, critical velocity above the critical flow rate promotes the release of PP in water.     

餐饮废弃物的危害及环境管理对策

介绍了餐饮废弃物的特点,处理不当污染环境,探讨餐饮废弃物无害化处理方式,并提出了针对餐饮业废弃物的环境管理对策。     

国家相关政策法规对石化企业建设项目环保管理的影响分析

分析了近期国家陆续出台的各项政策对中国石化建设项目管理的影响,并提出了对策建议.     

保护层分析应用规则研究

为了确保保护层分析(LOPA)结果的客观性和可靠性,对LOPA的应用规则进行了探讨.按照LOPA应用的基本程序,对场景筛选、确定初始事件、独立保护层评估、场景频率计算、风险决策及后续跟踪等的相关规则进行了阐述.企业在应用LOPA时,应严格按照这些规则进行.     

环境保护规划评估考核技术方法与实践研究

环境保护规划评估与考核是及时掌握规划实施进展、督促各方实施规划以及保障规划顺利实施的重要手段和措施。在探讨总结国内外公共部门规划政策实施绩效评估与考核工作的进展与经验基础上,分析归纳规划实施绩效的一般评估与考核方法,并结合《国家环境保护“十一五”规划》中期评估与终期考核具体实践,对未来环境保护规划的评估与考核工作提出了4条建议：（1）进一步加强评估考核的体制建设;（2）提高定性评估技术水平;（3）研讨评估技术的实际应用;（4）工程设施领域的评估内容应从重建设转向重运营。     

排污权交易指标关联要素探讨

目前,排污权有偿使用和交易作为各地环保工作体制、机制创新的热点,是利用经济手段促进环境保护的有益尝试。本文从指标来源、指标使用期限、与污染减排的关系、技术支撑以及指标交易后续监管五个方面分析了排污权交易指标关联要素,得出交易指标与国家政策、污染减排以及环境监管密切相关的结论,从完善国家政策、强化与污染减排衔接和突出指标后续监管三个方面提出了相应的对策建议。     

北京转河河岸带生态修复对河流水质的影响

以北京转河为例,探讨一系列河岸带生态修复措施(尤其是河漫地和护岸的改造)对河流水质的影响.于2009年7～9月进行实地调查,沿河岸选取13个采样点,并定期采集水样,测定其中营养物质和溶解氧(DO)等的浓度.结果表明,转河氨氮(NH4+-N)、硝氮(NO3--N)、总磷(TP)和DO的浓度均有非常明显的季节变化.在居民用...     

多菌种混合发酵转化秸秆技术的研究及应用进展

农作物秸秆是农业生产的副产品,也是一项重要的生物资源。利用微生物的广泛适应性和多功能性来转化秸秆已日益受到国内外科学研究者重视,特别是多菌种混合发酵是将秸秆纤维素转化为蛋白质、乙醇、乙酸等最具发展前景的方法。文章通过混合菌降解秸秆纤维,转化利用秸秆制蛋白饲料、燃料酒精、农用沼气等方面,对混合菌发酵转化秸秆技术的研究进展进行阐述。混合菌发酵转化秸秆已成为农业综合开发领域的一个亮点,正在朝着多元化,深层次的方向发展。     

王坡井田煤层气井采出水处理方法研究

针对王坡井田煤层气井采出水中污染物含量低,仅CODcr超出国家一级排放标准(GB 8978-1996)的特点,采用活性炭吸附处理,然后通过絮凝沉降迅速回收采出水中悬浮活性炭。结果表明:活性炭投加量为3g/L、吸附时间为40 min,PAM投加量为2 mg/L,沉降时间为5 min,活性炭回收率为98.35%,处理后采出水CODcr为45.45 mg/L、SS为7 mg/L,达到国家一级排放标准(GB 8978-1996)。