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汪学军 《环境污染治理技术与设备》2003,4(1):19-21
在反相微乳液体系(十六烷基三甲基溴化铵\正丁醇\异辛烷\水)中,用辣根过氧化物酶催化合成木质素—对甲酚共聚物,证实了反应的可行性。红外光谱的结果表明,木质素与对甲酚发生了聚合反应,差示扫描量热分析的结果也表明,引入对甲酚改善了木质素的热性能,合成的共聚物最高分子量可达189万。 相似文献
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对含有低浓度重金属离子的电镀废水进行处理研究,采用木质素磺酸盐与丙烯酰胺接枝共聚合成了一种木质素接枝共聚物,应用正交实验确定最佳操作条件,并通过红外光谱对其结构进行了表征.用这种改性木质素磺酸盐处理电镀废水,当其用量为90 mg/L,pH值控制在4~7,絮凝时间为2 h,在室温的条件下,可使电镀废水中的Cu2 、Zn2 、Pb2 和Ni2 去除率分别达到93%、90%、96%和90%以上. 相似文献
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《环境工程学报》2018,(11)
利用热重-傅里叶变换红外分析仪(TG-FTIR)和管式炉装置等技术,对木质素与豆粉和尼龙共热解及燃烧过程中有机氮释放规律进行了研究,分析了各温度下的协同效应。结果表明,热解工况下,豆粉和尼龙材料热解主要生成NH_3。当豆粉与木质素质量比达到1:1时,NH_3增加15.6%,但HCN降低了73.1%;对尼龙,加入同样比例的木质素可有效降低18.5%的NH_3。燃烧工况下,当豆粉与木质素质量比为3:1时,NO_x排放量仅为计算值的28.1%;木质素也使尼龙减排36.6%的NH_3。木质素对2种材料的作用机理不同,但都能有效降低热转化过程中含氮气体的排放。 相似文献
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造纸黑液木质素利用研究进展 总被引:29,自引:0,他引:29
本文对造纸黑液木质素利用研究现状进行了综述,内容包括木质素在肥料,混凝土减水剂,燃煤,水处理,石油开采,木材胶粘剂,橡胶补强剂和香兰素合成等方面的应用概况,这些技术成果是木质素工业化利用的重要基础,木质素来源丰富,具有优良的理化特性和广阔的应用前景,加强研究与应用开发对促进资源充分利用,环境保护制造纸协调持续发展意义重大. 相似文献
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综述了白腐真菌在不同反应器中合成木质素降解酶系能力的研究进展,包括培养方式与条件、不同反应器的特点及应用、木质素降解酶系的应用及前景. 相似文献
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分析了低DO下,乙酸钠、丙酸钠或葡萄糖作碳源,不同氧化还原电位(ORP)对活性污泥合成聚3-羟基丁酸-co-3-羟基戊酸酯(PHBV)的组分和产量的影响.结果显示,ORP从-30mV(厌氧)增加到 100mV(好氧),PHBV共聚物的产量增加,PHBV共聚物中3-羟基戊酸(HV)单体的摩尔分数降低,细胞生长量和碳源利用量增加;乙酸钠作单一碳源,ORP为-30mV时,PHBV共聚物中HV摩尔分数达到21.0%,ORP为 30mV时,PHBV共聚物在细胞内的质量分数达到35.0%.因此,DO是影响活性污泥合成PHBV共聚物的产量以及PHBV共聚物中HV摩尔分数的重要影响因素. 相似文献
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综述了白腐真菌在不同反应器中合成木质素降解酶系能力的研究进展,包括培养方式与条件、不同反应器的特点及应用、木质素降解酶系的应用及前景。 相似文献
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白腐菌降解木素酶系及其作用机理 总被引:1,自引:0,他引:1
制浆行业目标是脱除木质素,留下纤维素.白腐菌对木素的选择降解性能是造纸工业兴起研究领域如生物制浆,生物漂白及污染处理的理论基础.本文对有关白腐菌降解木素的酶系及作用机制作了概述,目的在于绘出一幅整体的木素降解酶系相互依存的图景,以便人们扩大视野,全面深入研究木素降解过程. 相似文献
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Borhan MS Capareda S Mukhtar S Faulkner WB McGee R Parnell CB 《Journal of the Air & Waste Management Association (1995)》2012,62(4):381-392
Although there are more than 200 odor-causing volatile organic compounds (VOCs), phenol and p-cresol are two prominent odor-causing VOCs found downwind from concentrated animal feeding operations (CAFOs). The VOC emissions from cattle and dairy production are difficult to quantify accurately because of their low concentrations, spatial variability, and limitations of available instruments. To quantify VOCs, a protocol following US. Environmental Protection Agency (EPA) Method TO-14A has been established based on the isolation flux chamber method and a portable gas chromatograph (GC) coupled with a purge-and-trap system. The general objective of this research was to quantify phenol and p-cresol emission rates (ERs) from different ground-level area sources (GLASs) in a free-stall dairy during summer and winter seasons using this protocol. Two-week-long sampling campaigns were conducted in a dairy operation in central Texas. Twenty-nine air samples were collected during winter and 37 samples were collected during summer from six specifically delineated GLASs (barn, loafing pen, lagoon, settling basin, silage pile, and walkway) at the free-stall dairy. Thirteen VOCs were identified during the sampling period and the GC was calibrated for phenol and p-cresol, the primary odorous VOCs identified. The overall calculated ERs for phenol and p-cresol were 2656 +/- 728 and 763 +/- 212 mg hd(-1) day(-1), respectively, during winter. Overall phenol and p-cresol ERs were calculated to be 1183 +/- 361 and 551 +/- 214 mg hd(-1) day(-1), respectively, during summer. In general, overall phenol and p-cresol ERs during winter were about 2.3 and 1.4 times, respectively, higher than those during summer. 相似文献
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Understanding foliar uptake processes for organic air pollutants is critical to predicting the fate of these compounds, including their entry into the food chain and their susceptibility to plant-, microbe-, and light-mediated degradation. We characterized the uptake kinetics for gaseous phenol and p-cresol into the leaves of maize seedlings in a closed system over periods up to 23h. When leaves were exposed to mixtures of phenol and p-cresol (3-50microg l(-1) each), the air concentrations of the compounds rapidly decreased, showing residence times of 4-6h. The stomata of the leaves were mostly or completely closed, suggesting that uptake was primarily through the cuticle. The involvement of a cuticular uptake pathway was confirmed based on increased uptake into two cuticular mutants of maize. Models of the uptake data suggested that, at the concentrations used, phenol and p-cresol were taken up in a biphasic manner, consistent with previous two-compartment models for foliar uptake of lipophilic compounds via a cuticular pathway. These models also indicated that phenol was taken up at a slightly faster rate than p-cresol. To begin to understand the fate of these compounds, we examined the location of (14)C in leaves exposed to (14)C-phenol. Significantly more (14)C accumulated in the terminal centimeter than in the central and basal regions of the leaves on both a mass and area basis. This is the first demonstration that a gaseous organic compound, or its breakdown products, accumulates in a spatially non-uniform manner in leaves following foliar uptake. These findings support a role for plants as natural, or deliberate, attenuators of airborne pollutants, and suggest potential availability of these compounds to the leaf surface microflora. 相似文献
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合成了一种用来吸附和去除水溶液中酚类化合物的 2 羧基苯甲酰基修饰的超高交联吸附树脂 (ZH 0 1) ,并从动力学和吸附容量角度比较了XAD 4、AM 1和ZH 0 1分别吸附浓度为 80 0mg/L苯酚的情况。实验结果表明 ,ZH 0 1吸附剂有利于吸附苯酚、对甲苯酚和对硝基苯酚之类的酚类化合物。动力学和热力学研究都得到了相同的结果 :ZH 0 1对苯酚和对甲苯酚吸附是化学吸附的过渡状态 ,而对对硝基苯酚的吸附是一种物理吸附过程 ,并且显示了ZH 0 1表面均孔特性。苯酚在ZH 0 1上的小柱吸附研究表明了吸附穿透容量和总吸附量分别为 2 .38mmol/g和 3.0 5mmol/g ,溶剂甲醇对吸附在ZH 0 1上苯酚的脱附效果较好。 相似文献
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Akio Yasuhara 《Chemosphere》1980,9(9):587-592
Odor similarity of the synthetically prepared solutions and the extract from solid swine manure showed that the main components for odor of solid swine manure are carboxylic acids and sulfides and that p-cresol increases the malodor and skatole modifies the nature of the malodor. 相似文献
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Bulliner EA Koziel JA Cai L Wright D 《Journal of the Air & Waste Management Association (1995)》2006,56(10):1391-1403
Livestock operations are associated with emissions of odor, gases, and particulate matter (PM). Livestock odor characterization is one of the most challenging analytical tasks. This is because odor-causing gases are often present at very low concentrations in a complex matrix of less important or irrelevant gases. The objective of this project was to develop a set of characteristic reference odors from a swine barn in Iowa and, in the process, identify compounds causing characteristic swine odor. Odor samples were collected using a novel sampling methodology consisting of clean steel plates exposed inside and around the swine barn for < or =1 week. Steel plates were then transported to the laboratory and stored in clean jars. Headspace solid-phase microextraction was used to extract characteristic odorants collected on the plates. All of the analyses were conducted on a gas chromatography-mass spectrometry-olfactometry system where the human nose is used as a detector simultaneously with chemical analysis via mass spectrometry. Multidimensional chromatography was used to isolate and identify chemicals with high-characteristic swine odor. The effects of sampling time, distance from a source, and the presence of PM on the abundance of specific gases, odor intensity, and odor character were tested. Steel plates were effectively able to collect key volatile compounds and odorants. The abundance of specific gases and odor was amplified when plates collected PM. The results of this research indicate that PM is major carrier of odor and several key swine odorants. Three odor panelists were consistent in identifying p-cresol as closely resembling characteristic swine odor, as well as attributing to p-cresol the largest odor response out of the samples. Further research is warranted to determine how the control of PM emissions from swine housing could affect odor emissions. 相似文献
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Relatively high concentrations of phenol, p-cresol, phenylacetic acid and other aromatic compounds were found in agricultural and communal sewage deposits. These toxic aromatic compounds are products of the bacterial degradation of aromatic amino acids under anaerobic conditions. In laboratory experiments at 26 degrees C and under N2-atmosphere, the same aromatics were formed from the amino acid tyrosine and from gelatine in assays inoculated with sewage sludge. After exhaustion of tyrosine and gelatine, respectively, concentrations of the accumulated phenol and other aromatics remained stable for months, i.e., phenol, p-cresol, phenylacetic acid etc. are dead-end products of the bacterial metabolism under these conditions. After addition of sodium nitrate the aromatic compounds are metabolically decomposed by denitrification within weeks. 相似文献