农作物秸秆炭制备速燃炭的研究

以农作物秸秆炭为主要原料制备速燃炭,研究了秸秆炭与引燃剂的比例及成型方式对速燃炭性能的影响,结果表明,农作物秸秆炭与引燃剂质量比为4:3,块状成型方式制备的速燃炭性能较好,其燃烧热为 21289.76 J/g,且 24 g 该速燃炭燃烧时火焰持续 13 min 55 s,火星持续 113 min,燃烧残渣 13.19%。并通过燃烧实验表明, 24 g 速燃炭能使 50 mL 蒸馏水持续沸腾 17 min,且水温在60~80℃ 之间保持 90 min 以上。     

Effective reduction of PAH contamination in smoke cured fish products using charcoal filters in a modified traditional kiln

Polycyclic aromatic hydrocarbons (PAHs) contaminations in Ghanaian smoke-cured fish are known to be in high levels. This may be linked to the recent upsurge of cancer cases among the population because PAHs are well-known carcinogens. A modified traditional kiln fitted with charcoal filters to remove PAHs by adsorption from the smoke before it contacted the fish being smoke-cured was designed. Smoke-curing was done for 4 h with three most used smoke wood types- in Ghana namely acacia, sugarcane bagasse and mangroves. The smoking was done with no charcoal filter and compared to smoking with two types of activated charcoals fitted to the designed traditionally modified kiln. PAHs in smoke-cured fish samples (n = 108) using the designed system were analysed using Varian GC/MS (3800-GC) system. The mean total PAHs levels in the experimental smoked fish samples analysed ranged from 212.56 to 472.98 μg/kg in samples smoke cured with – activated charcoal filters. The mean percent reductions (efficiency of Kiln) were 21–69%. The mean Benzo[a]pyrene levels in all fish cured using the modified traditional kiln with charcoal filters in place were below the Turkish Codex's maximum limit of 2.0 μg/kg. An ANOVA analysis conducted at 95% CL showed statistically significant differences (P < 0.05) in PAH levels between smoking with no charcoal filters and those with charcoal as filters. No statistical significant differences (P > 0.05) were obtained between the two smoking processes with charcoal filters. Fish obtained from the modified traditional kiln were of good organoleptic quality (moisture content < 65% as recommended) and the use of charcoal filters in fish smoking should be encouraged.     

竹炭制备与应用研究进展

竹炭因具有丰富的孔隙结构和巨大的比表面积,在水质净化、调湿抗菌、电磁屏蔽和电极材料等方面有着广泛应用.综述了竹炭的制备工艺、基本特性以及应用研究进展,重点介绍了竹炭在吸附、导电、辐射红外线和电磁屏蔽等方面应用的最新研究进展.     

Preparation,characterisation of bamboo charcoal particles and the effect of their application on thermo-physiological comfort properties of woven fabrics

Abstract

Bamboo charcoal particles were prepared at micro level and applied on three types of woven fabric, namely 100% cotton, 100% polyester and 65/35 p/c blend. The thermo-physiological comfort properties such as wetting, wicking, water vapour permeability, air permeability and thermal resistance of the control and treated fabrics were investigated to study the effect of bamboo charcoal particles application on these fabrics. The results reveal that the bamboo charcoal treated fabrics show a good improvement in wetting, wicking and water vapour permeability. The charcoal particle finished fabrics also showed a slight decrease in thermal resistance thereby contributing to a corresponding improvement in thermal conductivity with a reduction in air permeability when compared with the control fabrics. The bamboo charcoal treated fabrics showed a good fastness to washing thus exhibiting good durability on the fabrics selected for the study. Also, the charcoal treated fabrics revealed a higher wickability than the control fabrics even after 20 washes.     

Production of detoxified sorghum straw hydrolysates for fermentative purposes

Sorghum straw can be hydrolysed to obtain monosaccharide solutions, mainly containing xylose. The usual biotechnological application of xylose is its bioconversion to xylitol. The global process from straw to xylitol can give an added value to the sorghum straw. The process has the following sequential steps: reduction of size, acid hydrolysis, neutralization, detoxification, fermentation, recovery and purification. This work deals with the optimization of the detoxification process of sorghum straw hydrolysates with activated charcoal. The variables evaluated were pH (1–5), contact time (20–60 min) and activated charcoal charge (20–33 g kg^?1). Mathematical models were obtained through a factorial experimental design. The models suggest that optimal conditions for detoxification are pH 1, contact time of 29 min and a charcoal charge of 33 g kg^?1. These conditions allowed hydrolysates with 54.2 g xylose L^?1, 13.5 g glucose L^?1, 12 g arabinose L^?1, 0.2 g furfural L^?1 and 0.0 g acetic acid L^?1 to be obtained. The results suggest that performing the detoxification step before the neutralization step gave the best outcome. Fermentations by Candida parapsilosis NRRL Y‐2315 were performed and it was confirmed that the treated hydrolysate is suitable for xylitol production, yielding up to 17 g L^?1 of this polyol. Copyright © 2006 Society of Chemical Industry     

室内空气中甲醛污染控制研究

室内装饰材料及家具等释放的甲醛成为室内空气污染的特征污染物。通过对室内空气中甲醛的污染控制方法的研究发现,未装修居室空气中甲醛浓度与室外甲醛浓度无显著性差异;新装修和有新家具的居室室内空气中甲醛超标,而且污染程度与装修程度正相关,装修程度越高,污染越严重。活性碳对甲醛的平均吸附量为：5.83×10-3mg/m3.g。臭...     

中国竹炭产业研究新进展及发展建议

系统地总结了近年来我国竹炭的生产开发研究状况,综述了竹炭的应用领域,最后讨论了我国竹炭产业发展存在的问题,并提出建议.     

Detection of 5 CFU/g of Escherichia coli O157:H7 on lettuce using activated charcoal and real-time PCR without enrichment

A sample treatment method which separates Escherichia coli O157:H7 from lettuce and removes PCR inhibitors allowing 5 CFU/g of target cells to be detected using real-time PCR is described. Lettuce leaves inoculated with E. coli O157:H7 were rinsed with 0.025% sodium dodecyl sulfate (SDS). In this study, there were two major factors that strongly affected the recovery of E. coli O157:H7 during sample preparation, the amount of bentonite coated activated charcoal used to remove PCR inhibitors and the agitated contact time of the samples with the coated charcoal. When 3.0 g of activated carbon coated with bentonite were mixed with target cell suspensions (30 ml) derived from 50 g of lettuce, a high recovery of E. coli O157:H7 (93%) was obtained. Sample agitation with bentonite coated activated charcoal for 15 min resulted in 95% recovery of E. coli O157:H7. When a commercial DNA purification resin was used for detection of E. coli O157:H7 without the use of the bentonite treated charcoal, the real-time PCR (Rti-PCR) failed to detect 1 × 10² CFU/g. In contrast, with the use of use of bentonite coated activated charcoal and a commercial DNA purifying resin together, Rti-PCR was able to detect 5 CFU of E. coli O157:H7/g of lettuce which was equivalent to 2.8 CFU/Rti-PCR. Such a successful detection level was the result of the bentonite coated activated charcoal’s ability to absorb the PCR inhibitors released from seeded lettuce during detachment. A standard curve was generated by plotting the Ct values against the log of CFU of target bacterial cells. A linear range of DNA amplification was exhibited from 5.0 × 10⁰ to 1.0 × 10⁴ CFU/g by using Rti-PCR.     

回转冷却炉的设计

回转冷却炉用于冷却高温颗粒状的炭化料,冷却炉的设计结构能够使高温颗粒状炭化料在隔离空间内冷却,具体结构是把颗粒状物料和冷却介质通过换热管隔开,通过动静环密封使高温炭化料处于隔离空间内,使简体实现密闭状态下的旋转运动,高温炭化料住螺旋式前进的过程中被冷却到工艺要求的工况.     

Adsorption of bromo-phenol blue from an aqueous solution onto thermally modified granular charcoal

The adsorption phenomenon of bromo-phenol blue onto pristine and thermally evacuated granular charcoal (GC) was studied via a batch technique at 25 °C. The effect of evacuation temperature on the GC surface and pore structure (e.g. pore volume and diameter) was studied by Fourier transform infrared spectroscopy (FT-IR), point of zero charge (PZC), proximate analysis, Brunauer, Emmett and Teller (BET) method and field emission scanning electron microscopy (FE-SEM). The FT-IR spectra of the samples after evacuation showed considerable decrease in the acidic functional groups. PZC showed that the surface of the evacuated charcoal became basic as the evacuation temperature was increased from 300 to 800 °C. Volatile matter decreased while ash and fixed carbon contents increased during evacuation, which led to an increase in the micro-pore volume from 0.25 to 0.42 cm³ g⁻¹, meso-pore volume from 0.04 to 0.13 cm³ g⁻¹, pore diameter from 5.01 to 6.21 nm, and specific surface from 150.32 to 254.70 m² g⁻¹. Adsorption of the bromo-phenol blue onto charcoal, increased as the evacuation temperature was increased from 300 to 800 °C. The interaction of bromo-phenol blue with charcoal was proposed to have occurred via hydrogen bonding. The adsorption data fitted well with the Langmuir equation, which indicated that the monolayer adsorption has occurred at specific sites within the adsorbent.