含铜废催化剂中铜的回收

采用热解—氨浸工艺处理含铜废催化剂（w（Cu）为23.6%）,优化了工艺条件,并通过蒸氨还原法制备出Cu₂O产品。实验结果表明：热解工段中,控制管式热解炉的空气流量为3.0 m³/min,在升温速率20 ℃/min、热解终温600 ℃、终温保持时间90 min的优化条件下,含铜废催化剂中的有机物热解完全;氨浸工段中,以NH₄Cl-NH₃-H₂O溶液为氨浸液,控制氨浸温度为40 ℃,在烧成料研磨时间90 min（粒径29.43 μm）、氨浸液总氨浓度4 mol/L、氨浸时间80 min的优化条件下,铜浸出率达到98%;经蒸氨还原法制得的Cu₂O产品的质量符合HG/T 2961—2010《工业氧化亚铜》中的一等品标准,产率为24%。     

改性活性炭对石煤提钒废水中低浓度NH3-N和V等的吸附

为研究石煤提钒离交尾水的深度处理技术,利用质量分数为1%、5%和10%的过氧化氢溶液对ZWY15型活性炭进行改性,得到3种改性活性炭即1%AC、5%AC和10%AC;探讨其对该废水中低浓度的NH3-N、V等的吸附效果。实验结果表明:AC或改性AC的加入可使废水的碱度升高,随着吸附时间及吸附剂投加量的增加,升高幅度增大,且不同改性AC对废水碱度提高的幅度不同;相较于未改性活性炭,过氧化氢改性活性炭对V的吸附效果明显提高,去除率最大可提高30%,对NH3-N的去除率提升约11%;当投加量为60 g/L时,10%AC可使废水中V的浓度降低至1.88 mg/L,此时废水中Cr、Cd和Zn的浓度分别降低至0.006、0.010和0.036 mg/L,均低于《钒工业污染物排放标准》(GB26452-2011)所规定的排放限值。     

煤矸石制备Sialon材料影响因素研究

煤矸石还原氮化法制备Sialon材料的影响因素很多,主要有原料组成、反应温度和保温时间、添加剂的种类和用量、N2的流量和压强以及原料的粒度等.结合实验研究,分析了部分因素对制备Sialon材料的影响.     

碳纳米管电极原位产生过氧化氢及其对亚甲基蓝脱色效果

将碳纳米管固定化制成多孔疏水性导电薄膜构建电化学阴极还原体系,实现过氧化氢在阴极的原位产生。电极特性研究表明,电极在较宽的电压范围内均具有较好的活性。考察了阴极电位、电极成分、氧气流量和电解质浓度对过氧化氢原位产生的影响,在优化条件下经过120min后过氧化氢达到66．17mg／L,并探讨过氧化氢原位产生的机理。在此基础上考察原位过氧化氢氧化工艺下对亚甲基蓝的脱色效果,并分析其脱色机理。     

Increasing tree cover while losing diverse natural forests in tropical Hainan,China

To protect biodiversity and improve environmental conditions, China has invested billions of dollars in reforestation and payments for ecosystem service programs. Here, we examine the Sloping Land Conversion Program, the largest such program in the world and found that after 13 years of implementation at our study site, it has had negative impacts on natural tropical forests. GIS and remote sensing techniques revealed that both natural forests and natural shrub and grasslands were replaced by non-native monocultural plantations on Hainan Island, China, a key tropical biodiversity hotspot. Under current Chinese policy, these plantations are classified simply as “forests”, with the assumption that they are equivalent to natural forests. This lack of a distinction in forest quality has led to substantial deforestation and plantation expansion, including encroachment into protected areas on Hainan. Additional social and economic drivers of these changes were identified by examining the participants in this program and their actions. Without a new ecologically based definition of forests and new goals for reforestation, such programs designed to improve ecosystem services, and forest quality may actually threaten remaining natural forests and other vegetation types in Hainan and in other areas of mainland China.     

A novel pretreatment approach for fast determination of organochlorine pesticides in biotic samples

Recent studies have focused on enantiomeric behaviors of chiral organochlorine pesticides (OCPs) in biotic matrix because they provide insights into the biotransformation processes of chiral OCPs. In the present paper, a double in-line column chromatographic method was developed to effectively remove the lipid impurity in different biotic samples for clean-up of OCPs. After an initial Soxhlet extraction of OCPs from the biotic samples by a mixture of acetone and dichloromethane (DCM), dimethyl sulfoxide (DMSO) was directly added to the extract, and low boiling point solvents (acetone and DCM) were then evaporated. OCPs remained in DMSO were eluted via column 1 filled with silicon gel, and subsequently passed through column 2 packed with 15% deactivated florisil. This novel method was characterized by significant time and solvent savings. The recovery rates of α -HCH (hexachlorocyclohexane), β -HCH, γ -HCH and δ -HCH were 78.5 ± 3.1%, 72.4 ± 7.7%, 72 ± 4.0% and 70.0 ± 8.7%, respectively, and 92.5 ± 3.8%, 79.7 ± 6.7% and 83.4 ± 6.5% for 1,1-dichloro-2-(2-chlorophenyl)-2-(4- chlorophenyl) ethylene (o,p′-DDE), 1,1-dichloro-2-(2-chlorophenyl)-2-(4-chloro phenyl)ethane (o,p′-DDD) and 1,1,1-trichloro-2-(2-chlorophenyl)-2-(4-chlorophenyl) ethane (o,p′-DDT), separately. In addition, the separation efficiencies of the target compounds by both achiral and chiral gas chromatographic columns were satisfactory using the established method. Therefore, the double in-line column chromatography was a useful alternative method for pretreatment of OCPs in different biotic samples.     

Using variances in hydrocarbon concentration and carbon stable isotope to determine the important influence of irrigated water on petroleum accumulation in surface soil

Hunpu is a wastewater-irrigated area southwest of Shenyang. To evaluate petroleum contamination and identify its sources at the area, the aliphatic hydrocarbons and compound-specific carbon stable isotopes of n-alkanes in the soil, irrigation water, and atmospheric deposition were analyzed. The analyses of hydrocarbon concentrations and geochemical characteristics reveal that the water is moderately contaminated by degraded heavy oil. According to the isotope analysis, inputs of modern C3 plants and degraded petroleum are present in the water, air, and soil. The similarities and dissimilarities among the water, air, and soil samples were determined by concentration, isotope, and multivariate statistical analyses. Hydrocarbons from various sources, as well as the water/atmospheric deposition samples, are more effectively differentiated through principal component analysis of carbon stable isotope ratios (δ¹³C) relative to hydrocarbon concentrations. Redundancy analysis indicates that 57.1 % of the variance in the δ¹³C of the soil can be explained by the δ¹³C of both the water and air, and 35.5 % of the variance in the hydrocarbon concentrations of the soil can be explained by hydrocarbon concentrations of both the water and the air. The δ¹³C in the atmospheric deposition accounts for 28.2 % of the δ¹³C variance in the soil, which is considerably higher than the variance in hydrocarbon concentrations of the soil explained by hydrocarbon concentrations of the atmospheric deposition (7.7 %). In contrast to δ¹³C analysis, the analysis of hydrocarbon concentrations underestimates the effect of petroleum contamination in the irrigated water and air on the surface soil. Overall, the irrigated water exerts a larger effect on the surface soil than does the atmospheric deposition.     

“混凝气浮-膜生物反应器”处理林化废水工程运行调试研究

本文中根据林化废水特征确定使用"混凝气浮-膜生物反应处理器"的工艺进行处理。工程中硫酸铝的投加量为40mg/L,PAM的投加量为3mg/L,在废水pH值为7～8时进水COD、SS、OIL为279mg/L、20mg/L、26mg/L,进行混凝气浮后,出水的COD、SS、OIL浓度依次为135mg/L、9.6mg/L、9.5mg/L,去除率分别达到了52%、50%、64%。膜生物反应系统的调试,以污泥接种的方式进行污泥培养驯化。初期以面粉作为营养源清水培养污泥,按照7天左右的周期按每次30m3/d的污水进水量逐渐增加污水的比例,直到完全进水,调试驯化期污泥浓度控制在2500～3000mg/L。正常运转中污泥浓度可达到5000mg/L左右,出水水质COD、SS、OIL浓度分别达到30mg/L、6mg/L、3mg/L,符合处理目标要求。     

载Ni-Cu-K活性炭催化氧化法处理染料废水活性红X-3B

以载Ni活性炭为催化剂 ,用空气氧化模拟染料废水活性红X 3B。实验结果表明 ,负载在活性炭上的金属离子起到催化氧化的作用。活性炭对活性红X 3B的COD和色度的去除率能达到 98 74 %以上 ,较不加金属的活性炭去除率提高 30 % ,用活性炭处理浓度为 0 4g/L的模拟废水活性红X 3B ,投加量为 5g/L时 ,催化氧化效果最明显 ,催化氧化作用对色度的去除率达 2 5 33%。     

Co-pyrolysis of sewage sludge and biomass for stabilizing heavy metals and reducing biochar toxicity: A review

The huge amounts of sewage sludge produced by municipal wastewater treatment plants induce major environmental and economical issues, calling for advanced disposal methods. Traditional methods for sewage sludge disposal increase greenhouse gas emissions and pollution. Moreover, biochar created from sewage sludge often cannot be used directly in soil applications due to elevated levels of heavy metals and other toxic compounds, which alter soil biota and earthworms. This has limited the application of sewage sludge-derived biochar as a fertilizer. Here, we review biomass and sewage sludge co-pyrolysis with a focus on the stabilization of heavy metals and toxicity reduction of the sludge-derived biochar. We observed that co-pyrolyzing sewage sludge with biomass materials reduced heavy metal concentrations and decreased the environmental risk of sludge-derived biochar by up to 93%. Biochar produced from sewage sludge and biomass co-pyrolysis could enhance the reproduction stimulation of soil biota by 20‒98%. Heavy metals immobilization and transformation are controlled by the co-feed material mixing ratio, pyrolysis temperature, and pyrolysis atmosphere.