凹凸棒石土的性状及应用

凹凸棒石土的性状及应用王克孟，陈国英，马玉军，姜少军，姚可贵（江苏省淮阴市土肥站）凹凸棒石土是指含有凹凸棒石（Ａｔｔａｐｕｌｇｉｔｅ）矿物的土壤。在江苏省，它零星分布于丘陵岗地上，以淮阴市分布面积较大。近年来，我们对凹凸棒石土某些性状及应用进行了研究...

Application of Modified Attapulgite Clay as the Adsorbent in Gasoline Desulfurization

Attapulgite clay is a kind of special silicate mineral with high adsorption capacity thanks to its loose structure and porous surface. In this paper, the attapulgite clay was treated effectively with acid under microwave thermal activation and ultrasonic vibration, respectively, and characterized by XRD, N2 adsorption, FT-IR and SEM. The desulfurization performance of the modified attapulgite clay was then evaluated by using simulated gasoline as the feed. The test results showed that the thiophene removal rate increased with an increasing dosage of hydrochloric acid during microwave modification of attapulgite clay. When the concentration of hydrochloric acid reached 15%, the increase of desulfurization rate became slower, and the desulfurization rate was about 69%.

Dynamic Adsorption of Microwave Modified Attapulgite on Micro-polluted Phenol Wastewater

[Objective] The paper was to study the dynamic adsorption of microwave modified attapulgite on micro-polluted phenol wastewater. [Method] Cetyl trimethyl ammonium bromide （CATB） modified attapulgite was used to modify attapulgite, and conducted dynamic test on micro-polluted phenol wastewater. The dynamic charac- teristics of phenol removal were also studied. [Result] Attapulgite modified by CATB has strong adsorption ability on phenol in micro-polluted water, the phenol removal rate increased with the decrease of flow rate of wastewater. When pH value was 6- 8, phenol concentration in wastewater was 17.74 mg/L, flow rate was 2 m/s and ad- sorption time was 25 rain, the removal rate reached 93.07%. The modified atta- pulgite could be regenerated with alkali, and its adsorption ability after regeneration had no obvious decline. The dynamic adsorption process of phenol accorded with the first-order kinetic equation. [Conclusion] The study provided basis for further study on ＂organic matter removal in wastewater.

高粘度凝胶制胶工艺技术的研究

高粘度凝胶,融有高粘度粘结剂与A凝胶两者特性的新型产品。本项目着重研究了以凹凸棒石粘土制备的高粘度A凝胶及其制胶新工艺,粘度值≥6 500mPa.s、触变性≥110%时,锂化、纳化、助效技术,以及干燥效应、胶粉湿度、粒度和介质酸碱度等因素对产品的技术作用。透过互动技术因素的作用关系,为高粘度凝胶提出新工艺技术路线。

Copper-modified palygorskite is effective in preventing and treating diarrhea caused by Salmonella typhimurium

The aim of this research was to develop effective alternative therapies to reduce antibiotic use in animal agriculture. In this study, the efficacy of copper-modified palygorskite（CM-Pal） in preventing diarrhea caused by Salmonella was specifically examined both in vitro and in vivo. The CM-Pal was prepared with palygorskite（Pal） and copper nitrate. The antibacterial activity of the CM-Pal was detected by comparing the differences in cell numbers on plate count agar before and after adding the CM-Pal to Salmonella typhimurium cultures. Seventy ICR mice were then allocated into seven groups. Five groups（the treatment groups） were infected with S. typhimurium by intraperitoneal（i.p.） injection and were given Pal, CM-Pal, montmorillonite powder, gentamicin, and physiological saline, respectively. One group（the prevention group） was given CM-Pal before infection with S. typhimurium. Another group（the uninfected group） was not infected with S. typhimurium. The effects of Pal, CM-Pal, montmorillonite powder, and gentamicin on the treatment or prevention of diarrhea in the mice were examined by stool studies, fecal scoring, and assessment of growth performance and villus height. The CM-Pal had satisfactory anti-bacterial properties in vitro： the antibacterial rate was 100% after 2 h incubation with S. typhimurium NJS1 cultures（1×10-6 colony-forming units（CFU）/ml）. In the in vivo experiment, the CM-Pal exerted superior effects in the treatment and prevention of diarrhea in mice compared with Pal, montmorillonite powder, and gentamicin. In the CM-Pal group, no mice showed signs of diarrhea at 24 h post infection（p.i.）, and all mice fully recovered from infection. However, the Pal group, montmorillonite group, and gentamicin group only recovered after 48, 48, and 96 h, respectively. The villus height level in the CM-Pal treatment group recovered at 3 d p.i. However, the recovery time of the other groups was longer（at least 5 d）. The CM-Pal prevention group had a better effect on weight gain than the other groups. This study suggested that CM-Pal may be an effective alternative to conventional antibiotics for the treatment and prevention of animal diarrhea caused by Salmonella.

The sorption mechanisms of Th(Ⅳ) on attapulgite

The surface properties of intrinsic and activated attapulgite were studied using potentiometric titration. The sorption mechanisms of Th（IV） on intrinsic and activated attapulgite were investigated by employing surface complexation model and FITEQL 3.2 code. The results indicated that the sorption sites of intrinsic attapulgite involved in the sorption process were main ion exchange site （ ≡ XNa/K）, strong site （≡ SsOH） and weak site （ ≡ SwOH）, while only strong site （ ≡SSOH） and weak site （≡SwOH） were predominant for activated attapulgite. At pH 〈 2.5, the species of Th（IV） was main Th4＋ in aqueous solution; then the hydrolysis species of Th（IV） （i.e., Th（OH）22＋, Th（OH）3＋ and Yh（OH）40） gradually formed as pH increasing. For the sorption of Th（IV） on intrinsic attapulgite, both ion exchange species （ ≡ X2Th） and inner-sphere surface complexes （ ≡ SsOTh） were dominant, while only inner-sphere surface complexes （i.e., ≡SSOThOH and ≡ SWOTh） were observed for Th（IV） sorption to activated attapulgite. In the presence of humic acid （HA）, the sorption of Th（IV） on activated attapulgite was obviously enhanced; and both ≡ SsOH-HA-Th and≡ SSOTh were the predominant speciation. It was also interesting to find that the addition of HA obviously provoked the desorption behavior of Th（IV）.