Feasibility of honeycomb monolith supported sugar catalyst to produce biodiesel from palm fatty acid distillate (PFAD)

Carbon coated monolith was prepared by sucrose solution 65 wt.% via dip-coating method. Sulfonation of incomplete carbonized carbon coated monolith was carried out in order to synthesize solid acid catalyst. The textural structure characteristics of the solid acid catalyst demonstrated a low surface area and pore volume. Palm fatty acid distillate (PFAD), a by-product of palm oil refineries, was utilized as oil source in biodiesel production. The esterification reaction subjected to different reaction conditions was performed by using the sulfonated carbon coated monolith as heterogeneous catalyst. The sulfonation process had been performed by using vapour of concentrated H₂SO₄ that was much easier and efficient than liquid phase sulfonation. Total acidity value of carbon coated monolith was measured for unsulfonated sample (0.5 mmol/g) and sulfonated sample (4.2 mmol/g). The effect of methanol/oil ratio, catalyst amount and reaction time were examined. The maximum methyl ester content was 89% at the optimum condition, i.e. methanol/oil molar ratio (15:1), catalyst amount (2.5 wt.% with respect to PFAD), reaction time (240 min) and temperature 80 °C. The sugar catalyst supported on the honeycomb monolith showed comparable reactivity compared with the sugar catalyst powder. However, the catalyst reusability studies showed decrease in FFA% conversion from 95.3% to 68.8% after four cycles as well as the total acidity of catalyst dropped from the value 4.2 to 3.1 mmol/g during these cycles. This might be likely due to the leaching out of SO₃H group from the sulfonated carbon coated monolith surface. The leaching of active species reached a plateau state after fourth cycle.     

A Global Overview of Atmospheric Acid Deposition Fluxes

This paper presents a summary of globalacid deposition flux data taken from a globalassessment report on acid deposition prepared forUNEP/WMO (Whelpdale and Kaiser, 1996). There is a largevariation in the spacial coverage and reliability ofmonitoring around the world. Many more stationsmeasure wet deposition than collect appropriate datafor estimating dry deposition. The widespread regionswith highest precipitation concentrations anddeposition fluxes of sulphate and nitrate coincideclosely with the regions of highest density ofSO₂ and NO_x precursor emissions occurringprimarily in the mid-latitude, northern hemispherebelt where a large fraction of the worlds fossilfuels is consumed. Organic acids in precipitation makea minor contribution to acidity (<20%) inindustrial regions, but in the rest of the world theyare of same order, or even exceed, inorganic acids.Less is known about dry deposition, but it appears topredominate near strong emission sources with wetdeposition predominating farther downwind. The molarratio of the N/S contribution to acidic deposition isclose to 1.0 over large areas of Europe and NorthAmerica, but is highly variable elsewhere, beinghighest in equatorial regions due to biomass burningand lowest near smelters and other large sources of SO₂.     

Kinetics of photoelectrocatalytic degradation of humic acid using B_2O_3·TiO_2/Ti photoelectrode

IntroductionEightypercentoforganicsubstancesinthesourcewaterisfromcrudehumicacidthatisacrudeorganiccompoundcreatedbyrottinganddecomposinginnaturalcycle ,thehighercontentofhumicacidis ,theworsequalityofthewateris,notonlycanitcausechrominance,offensiveodor,…     

Preparation of rare-earth metal complex oxide catalysts for catalytic wet air oxidation

Catalytic wet air oxidation (CWAO) is one of the most promising technologies for pollution abatement. Developing catalysts with high activity and stability is crucial for the application of the CWAO process. The Mn/Ce complex oxide catalysts for CWAO of high concentration phenol-containing wastewater were prepared by coprecipitation. The catalyst preparation conditions were optimized by using an orthogonal layout method and single-factor experimental analysis. The Mn/Ce serial catalysts were characterized by Brunauer-Emmett-Teller (BET) analysis and the metal cation leaching was measured by inductively coupled plasma torch-atomic emission spectrometry (ICP-AES). The results show that the catalysts have high catalytic activities even at a low temperature (80°C) and low oxygen partial pressure (0.5 MPa) in a batch reactor. The metallic ion leaching is comparatively low (Mn<6.577 mg/L and Ce<0.6910 mg/L, respectively) in the CWAO process. The phenol, COD_Cr, and TOC removal efficiencies in the solution exceed 98.5% using the optimal catalyst (named CSP). The new catalyst would have a promising application in CWAO treatment of high concentration organic wastewater. Translated from Techniques and Equipment for Environmental Pollution Control, 2005, 6(2): 40–44 [译自: 环境污染治理技术与设备]     

石油亚砜萃取巯基醋酸的研究

对石油亚砜(PSO)萃取巯基醋酸的条件和影响进行了实验研究,确定了石油亚砜通过氢键和巯基醋酸形成的萃合物的组成.为从废水中回收巯基醋酸以及石油硫醚的综合利用提供了依据.     

H酸综合废水治理工艺试验研究及工程应用

针对H酸母液及T酸一次洗水高含盐量有机废水进行系统的实验研究，结果表明：废水经冷却、结晶、过滤后，用铁屑过滤，石灰乳、PAM处理．使废水COD去除率为50％，脱色率为7O％，BOD／CODcr提高到0．2以上，预期COD去除率达60％以上，BOD去除率达85％以上，NH3—N去除率达80％以上．     

A novel technology for quick acclimation of an anaerobic microbial consortia used for biodegrading teraphthalic acid (TA)

ＩｎｔｒｏｄｕｃｔｉｏｎＴｅｒａｐｈｔｈａｌｉｃａｃｉｄ (ＴＡ)ｉｓｏｎｅｏｆｔｈｅｐｅｔｒｏｃｈｅｍｉｃａｌｓｗｉｄｅｌｙｕｓｅｄｉｎｔｈｅｓｙｎｔｈｅｓｉｓｏｆｐｏｌｙｅｓｔｅｒｆｉｂｅｒ,ｖｉｄｅｏｆｉｌｍｓａｎｄｏｔｈｅｒａｐｐｌｉｃａｔｉｏｎｓ .Ｓｉｎｃｅｂｉｓ (2 ｅｔｈｙｌｈｅｘｙｌ)ｐｈｔｈａｌａｔｅ ,ｄｉｅｔｈｙｌｐｈｔｈａｌａｔｅａｎｄｄｉｍｅｔｈｙｌｐｈｔｈａｌａｔｅｈａｖｅｂｅｅｎｃｌａｓｓｉｆｉｅｄａｓｐｒｉｏｒｉｔｙｈａｚａｒｄｏｕｓｃｏｍｐｏｕｎｄｓｂｙＥＰＡｏｆｔｈｅ…     

UASB-BIOFOR滤池组合工艺处理柠檬酸废水的中试研究

采用UASB-BIOFOR滤池组合工艺处理柠檬酸废水,对其中的操作步骤及注意事项进行了详细介绍.实验结果表明,该组合工艺对柠檬酸废水处理效果良好,系统出水能够达到GB 8978-1996《污水综合排放标准》中的一级标准.     

从自燃煤矸石中提取聚合铝铁(PAFC)的试验研究

采用盐酸酸浸的方法从自燃煤矸石中提取聚合铝铁，对煤矸石的粉碎粒径、酸浸盐酸的浓度及用量、酸浸的温度等工艺条件进行了试验研究。结果表明，从100g自燃煤矸石中，可提取19．85g固体聚合铝铁，成品的Al2O3含量33％、Fe2O3含量16％、盐基度70％。     

Fulvic acid removal by nanoparticle TiO2 using a submerged membrane photocatalysis reactor

The degradation of fulvic acid（FA） by nanoparticle TiO2 in a submerged membrane photocatalysis（SMPC） reactor was studied. In this reactor, photocatalytic oxidation and membrane separation co-occured. The continuous air supplier provided O2 for the photocatalytical reaction and mixed the solution through an airflow controller. The particle TiO2 could automatically settle due to gravity without particle agglomeration so it could be easily separated by microfiltration（MF） membrane. It was efficient to maintain high flux of membranes. The effects of operational parameters on the photocatalytic oxidation rate of FA were investigated. Results indicated that photocatalyst at 0.5 g/L and airflow at 0.06 m^3/h were the optimum condition for the removal of fulvic acid, the removal efficiency was higher in acid media than that in alkaline media. The effects of different filtration duration on permeate flux rate of MF with P25 powder and with nanoparticle TiO2 were compared. Experimental results indicated that the permeate flux rate of MF was improved and the membrane fouling phenomenon was reduced with the addition of nanoparticle TiO2 catalyst compared with conventional P25 powder. Therefore, this submerged membrane photocatalysis reactor can faciliate potential application of photocatalytic oxidation process in drinking water treatment.