高性能煤基活性炭的制备与性能评价

针对煤基活性炭性能不佳的问题,以太西煤(TX)和灵武煤(LW)为原料,通过对配煤、炭化、活化等工艺的优化,从而制备一种高性能活性炭,并对制备的活性炭进行孔结构表征和柴油吸附脱硫性能评价。结果表明,该活性炭制备的优化工艺条件为:配煤质量比为89%TX+11%LW、活化剂(KOH)质量分数0.8%、炭化温度600℃、升温速率为10℃/min;活化温度850℃。改进工艺后煤基活性炭的比表面积和微孔面积与椰壳活性炭相近,分别为984.94 m^2/g和713.30 m^2/g;其吸附脱硫性能达到或超过了椰壳活性炭的性能。

Controllable preparation of ZnO porous flower through a membrane dispersion reactor and their photocatalytic properties

Three dimensional (3D) flower-like basic zinc carbonate constructed by multilayered nanoplates were rapidly prepared at room temperature through the direct precipitation method coupled with membrane dispersion technology, and porous ZnO with similar structures could be obtained after calcining the precursor. The structural properties of the products before and after the calcining process were characterized by SEM, TEM and XRD.The supersaturation of the reaction system due to the membrane dispersion played an important role in the formation of uniform Zn_5(CO_3)_2(OH)_6 precursors. A plausible mechanism was proposed for the formation of the flower-like ZnO assembled by nanoplates composed of nanoparticles. The obtained ZnO microspheres showed excellent photocatalytic properties, which could be attributed to the open structure and remarkable amount of porous nanoplates.

Field investigation into directional hydraulic fracturing for hard roof in Tashan Coal Mine

t Research and development of safe and effective control technology of hard roof is an inevitable trend at present. Directional hydraulic fracturing technology is expected to become a safe and effective way to control and manage hard roof. In order to make hard roof fracture in a directional way, a hydraulic fracture field test has been conducted in the third panel district of Tashan Coal Mine in Datong. First, two hydraulic fracturing drilling holes and four observing drilling holes were arranged in the roof, followed by a wedge-shaped ring slot in each hydraulic fracturing drilling hole. The hydraulic fracturing holes were then sealed and, hydraulic fracturing was conducted. The results show that the hard roof is fractured directionally by the hydraulic fracturing function of the two fracturing drilling holes; the sudden drop, or the overall downward trend of hydraulic pressure from hydraulic monitoring is the proof that the rock in the hard roof has been fractured. The required hydraulic pressure to fracture the hard roof in Tashan coal mine, consisting of carboniferous sandstone layer, is 50.09 MPa, and the fracturing radius of a single drilling hole is not less than 10.5 m. The wedge-shaped ring slot made in the bottom of the hydraulic fracturing drilling hole plays a guiding role for crack propagation. After the hydraulic fracturing drill hole is cracked, the propagation of the resulting hydraulic crack, affected mainly by the regional stress field, will turn to other directions.

Research on the control technology of medium-length hole blasting fragmentation in underground mine

The scalloped medium-length hole blasting mining method used in Dahongshan Copper Mine accounted for more than 61%of the total amount of mining,but the large boulder yield restricted the intensity of ore supply for mines,and the average boulder yield was as high as 22.7%.In order to develop the mine production efficiency,the circular medium-length hole blasting technology was proposed and field tests were carried out.The test results showed that circular medium-length hole blasting mining can reduce the average boulder yield to 10.3%.Compared with the traditional scalloped medium-length hole blasting mining,the average boulder yield was decreased by 12.4%.The daily yield of ore for the panel on duty was increased by 152.29 t,and the growth rate was 51.1%.The new technology can reduce the time for the handling of boulder and the consumption of explosives and detonators for recrushing,and increase the efficiency of mining while reduce the mining cost,which has received good blasting effects.

Band Gap Control for （Fe, Ti）-Containing Mesoporous Silica Nanoparticles Using the Photo-Assisted Deposition Technique

It is a great advantage to design advanced materials with outstanding porosity and controllable band gab. In this study, （Fe, Ti）-containing mesoporous silica （x Fe/Ti-HMS） nanoparticles were prepared by a photo-assisted deposition PAD technique, where x is a nominal composition ofFe （l to 4 wt%））. The prepared samples were characterized by DR-UV, XRD, and TEM techniques. The results showed the insertion of Fe into intra-framework of Ti-HMS resulted in a gradual narrowing of the band gap of Ti-HMS samples with increment of Fe wt%. TEM observations reveal that Fe nanoparticles are evenly distributed within Ti-HSM matrix at different Fe wt%. Such results indicate the possibility to control the band gap of a single-site photocatalyst （Ti-HMS） by coupling it with the conventional nano-sized Fe catalysts.