Effect of 2-butenal manufacture wastewater to methanogenic activity and microbial community

The synthesis of 2-butenal,which is a vital raw material for the production of sorbic acid as a food preservative,generates some toxic by-products,so it is urgent to seek better detoxification strategies for the treatment of 2-butenal manufacture wastewater.In this study,batch experiments were carried out to investigate the inhibition effect of wastewater on the methanogenic activity.To understand the wastewater toxicity to anaerobic granular sludge,variations of the specific methanogenic activity(SMA)and extracellular polymeric substance(EPS)constituents at various wastewater CODs were investigated.Ultraviolet-visible(UV-vis)spectra and Fourier transform infrared(FT-IR)spectra were employed to analyze the structure of the EPS.The results showed that the inhibitory ratio of 2-butenal manufacture wastewater was less than 8.4%on the anaerobic granular sludge when the CODs were less than 959 mg/L.However,the inhibitory ratio increased from 36.4%to 93.6% when CODs increased from 2396 mg/L to 9585 mg/L,with the SMA decreasing from 39.1 mL CH4/(gVSS·d)to 3.2 mL CH4/(gVSS·d).The diversity of the microbial community under various CODs was researched by Illumina 16S rRNA Miseq sequencing and the results demonstrated that Proteiniphilum、Petrimonas and Syntrophobacter were the dominant bacteria genera in all sample.Regarding archaea,Methanobacterium was the most dominated archaea genera,followed by the Methanosaeta group in all samples.Moreover,the bacterial communities had changed obviously with increasing CODs,which indicated high CODs played a negative impact on the richness and diversity of bacterial community in the sludge samples.

Effect of Reaction Temperature and Pressure on the Metathesis Reaction between Ethene and 2-Butene to Propene on the WO_3/Al_2O_3-HY Catalyst

Effect of reaction temperature and pressure on the metathesis reaction between ethene and 2-butene to propene was studied on the WO3/γ-Al2O3-HY catalyst. The activity is found to increase with elevated temperature and reaches a plateau at 150-240 ℃. After that, the activity undergoes a remarkable decrement at too high temperature. The effect of temperature is elucidated by the oxidation state of tungsten species. The evaluation results also indicate that the stability is dependent on this reaction parameter. Medium pressure （0.5-0.8 MPa） is favorable for stability, while atmospheric pressure or too high pressure （〉1.0 MPa） deteriorates the stability. For explanation, UV Vis, FT-IR, O2-TPO, and TG techniques are used to characterize the spent catalysts.

A mild,efficient and selective iodination of aromatic compounds using iodine and 1,4-bis(triphenylphosphonium)-2-butene peroxodisulfate

A simple and efficient method for the iodination of aromatic compounds has been achieved in the presence of iodine and 1,4- bis（triphenylphosphonium）-2-butene peroxodisulfate.

Synthesis of Some Novel 2,3-diaryl-Butadiene Analogues

In present paper, the 2,3-diaryl-butadiene analogues were synthesized as anti-cancer agents. The structures were confirmed by (HNMR)-H-1 and elemental analysis.

Dehydrogenation of n-Butane to Butenes and 1,3-Butadiene over PtAg/Al₂O₃Catalysts in the Presence of H₂

The Al2O3-supported PtAg catalysts were prepared and evaluated for the dehydrogenation of n-butane at 550°C in the presence of H2. The PtAg/Al2O3 catalyst prepared by an impregnation method using the Cl- removing Pt/Al2O3 and AgNO3 showed a higher activity and selectivity to butenes and 1,3-butadiene compared to the Pt/Al2O3 catalyst, but a large amount of coke (about 30 wt% versus the catalyst weight) was formed during the dehydrogenation. The free Ag metal on the prepared catalyst dramatically promoted the coke formation, because the dehydrogenation of 1-butene over the Ag/Al2O3 catalyst produced a large amount of coke. The Cl- addition to the Cl- free Pt/Al2O3 catalyst decreased the coke formation by the reaction of the free Ag particles and Cl to form AgCl which was inactive for the coke formation. The highest initial conversion (50.3%) was obtained with the selectivity to butenes and 1,3-butadiene (butenes = 80.2% and 1,3-butadiene = 5.9%) when the PtAg/Al2O3 catalyst modified with Cl- was used.

Improvement of Isomerization Process of Crude Isoamylene with Tertiary-amyl-alcohol Addition

The present work contributed to a new developed production method for enhancing the quality of isoamylene （IA） by adding a small amount of tertiary amyl alcohol （TAA） to the catalyst of strong acid cation exchange resin. TAA improved the selectivity of 2-methyl-2-butene （2M2B） at a high conversion level for the isomerization of IA. Compared with the other results from the current IA units, the conversion of 2-methyl- 1-butene （2M1B）, the mass ratio of 2M2B to 2M1B and the selectivity of 2M2B were increased from 0.5474, 7.32 and 0.6864 to 0.72, 12 and 0.95, respectively, while the dimers content in the products decreased from 4.38% to below 1.0%. Optimized conditions for IA isomerization consisted of temperature between 28 and 33℃ and system pressure of 0.5 MPa, weight hourly space velocity of 8.0 h-1 with TAA mass fraction of 0.7%-0.9% in raw material. The results in lab supported bases for the developed process in industrial application which was later proved to be successful. In addition, a possible mechanism of the isomerization process was speculated to propose a key step of water formation in the TAA-added isomerization process and a verified experiment was conducted to support this speculation.

A novel and efficient synthesis of alkyl thiocyanates from alkyl halides in water using phase transfer catalysts

1,4-Bis（triphenylphosphonium）-2-butene dichloride（BTPBDC） and 1,4-bis（triphenyl phosphonium）-2-butene dithiocyanate （BTPBDT） were prepared and used as phase-transfer catalysts.Alkyl halides were converted efficiently to the corresponding alkyl thiocyanates under mild reaction conditions in water.No evidence for the formation of isothiocyanates as by-product of the reaction was observed.