PREPARATION AND CHARACTERIZATION OF POLYMER-BASED SPHERICAL ACTIVATED CARBONS

A series of spherical activated carbons(SACs)with different pore structures were prepared from chloromethylated polydivinylbenzene by ZnCl_2 activation.The effects of activation temperature and retention time on the yield and textural properties of the resulting SACs were studied.All the SACs are generated with high yield of above 65% and exhibit relatively high mesopore fraction(me%)of 35.7%-43.6% compared with conventional activated carbons.The sample zlc28 prepared at 800℃for 2 h has the largest BET surf...

Adsorption of urea,creatinine,and uric acid from three solution types using spherical activated carbon and its recyclability

In this paper,we propose that the urinary toxins from the wastewater be adsorbed on an adsorbent such as spherical activated carbon and the latter be regenerated by subjecting it to high temperatures to recycle activated carbon and also to recycle the water used in dialysis.We studied the adsorption of artificial waste dialysate,which is a mixed solution of urea,creatinine,and uric acid,and the separate solutions for each of these and found that their extents of adsorption onto the spherical activated carbon material were nearly identical.The amount of adsorption was approximately 1.4 mg·g^−1 for urea,18 mg·g^−1 for creatinine,and 20 mg·g^−1 for uric acid.The urea,creatinine,and uric acid adsorbed onto the spherical activated carbon decomposed on heat treatment at 500℃,and the adsorption capacity of the spherical activated carbon was regenerated.Our study successfully demonstrated that the spherical activated carbon can be recycled in the waste dialysate treatment process.

Melamine Modification of Spherical Activated Carbon and Its Effects on Acetylene Hydrochlorination

Commercial spherical activated carbon（SAC） was modified by impregnation to enhance the catalytic properties of SAC in acetylene hydrochlorination through melamine modification. Different modification conditions for SAC with nitrogen were compared by changing the SAC-Melamine ratios. The effect of carbonization temperature on the modification was also investigated. Surface chemistry and adsorption properties of the modified and unmodified SACs were studied by scanning electron microscope（SEM）, X-ray photoelectron spectroscopy（XPS）, elementary analysis, BET, and temperature-programmed desorption（TPD）. Moreover, the catalytic properties of SAC in acetylene hydrochlorination under differently modified conditions were also investigated. Elemental analysis showed that the nitrogen content of the modified SAC was greatly improved. XPS revealed that nitrogen mainly exists in Pyrrole nitrogen and Pyridine nitrogen. TPD showed that desorption of C2H2 was changed by modification. The conversion rate of acetylene was up to 70% under the following reaction conditions： temperature, 150 ℃; C2H2 hourly space velocity（GHSV）, 36 h-1; feed volume ratio V（HCl）/V（C2H2） = 1.15. The catalytic properties of SAC were improved significantly via melamine modification.

Development of covalent-organic frameworks derived hierarchical porous hollow carbon spheres based LiOH composites for thermochemical heat storage

Under the joint assistance of its excellent storage strength, accessible long storage lifespan, and high heat utilization efficiency, salt hydrate-based thermochemical heat storage(THS) materials give renewable energy an important outlet to alleviate the pressure of underutilization. Herein, an activated hollow spherical carbon(AHSC) with hierarchical porous architectures converted from covalent-organic frameworks(COFs) is constructed and utilized as the supporting matrix for Li OH.THS composite material for the first time. The obtained Li/AHSC_(3) composites have distinguished hydration performance while manifesting impressive storage ability up to 1916.4 k J kg^(-1)with low operating temperature stemming from the collective effect of the void spherical framework, multimodal porosity, and high surface area of AHSC3. And the Li/AHSC3-40 composite with evidently progressed thermal conductivity is capable of realizing 94.5% heat preservation after twenty-five adsorption-desorption cycles, exhibiting its eminent cyclability and great heat transfer performance. This study not only brings new hope for overcoming the underutilization of low-grade heat but also may enlighten new ideas for enriching the application scenarios of COFs-derived carbonaceous materials.