Study on Adsorption Removal of Polycyclic Aromatic Hydrocarbons by Modified Mussel Shells

Polycyclic aromatic hydrocarbons(PAHs)are typical persistent organic pollutants(POPs)that are commonly found in the environment.They are carcinogenic,teratogenic,mutagenic and biodegradable obviously.In this paper,the modified mussel shells were used to adsorb and remove anthracene.The results show that the adsorption removal rate of the mussel shells was higher after calcination at 600℃.5%H_(3)PO_(4) solution was more suitable for shell treatment than 3 mol/L ZnCl_(2) solution.As the dosage of the modified shells was 0.5 g/L,the adsorption reached a stable state,and the removal rate of PAHs was about 69.44%;the adsorption efficiency rose with the increase of time.It can be seen that as a new and cheap biological adsorbent,the modified shells can be used to remove PAHs from wastewater.

Effects of Phosphorus Concentration on the Treatment of Domestic Wastewater by a Combination of Hydrolytic Acidification and Biological Aerated Filter Filled with Mussel Shells

The combination of hydrolytic acidification and biological aerated filter （BAF） filled with mussel shells was used to treat domestic wastewater, and the removal rates of chemical oxygen demand （COD）, ammonia nitrogen （NH3-N） and total phosphorus （TP） by the system were analyzed under different TP concentrations. When TP concentration ranged from 12.39 to 14.69 mg/L, the removal rate of COD was the best, over 90.92% ; as TP concentration varied from 2.26 to 2.61 mg/L, the removal rates of NH3-N and TP were the best, up to 100.00% and 76.38% respectively. The results show that it is feasible to use mussel shells as the media of BAF, and TP concentration has certain influence on the performance of the system dealing with domestic wastewater.

Preparation of Porous Materials Derived from Waste Mussel Shell with High Removal Performance for Tableware Oil

In this work,carbonized mussel shell powder(CMSP)was modified by alkyl polyglucosides(APG)and rhamnolipid(RL)to render porous biomass a lipophilic surface,which was innovatively utilized as an environmentally friendly tableware cleaning material.The modified method was two-step hydrotherm-assisted synthesis.A contact angle meter was used to determine the surface hydrophobic property of modified samples(MTAR).The pore and the surface structure of CMSP and MTAR were characterized by BET,SEM,XRD,FTIR and XPS.The effect of removing oil was tested by gravimetric method.The results showed that the surface of MTAR was more porous and fluffier than CMSP,and the specific surface area is increased by 16.76 times.The results showed that when calcining CMSP at 1000℃,the oil removal rate of the synthesized MTAR is the best,and the decontamination rate can reach 87.05%.This research aims to develop a green and environmentally-friendly tableware cleaning material,solve environmental problems,and make full use of waste,which is very conducive to environmental protection.

Beneficial use of mussel shell as a bioadditive for TPU green composites by the valorization of an aqueous waste

Scientific studies have focused on environmentally friendly solutions as effective as the reuse of crop products owing to plastic-waste problems in recent years.This issue is the main driving force for upcoming academic research attempts in waste valorization-related studies.Herein,we integrated an aqua-waste,mussel shell(MS),as a bioadditive form into green thermoplastic polyurethane(TPU)green composites.Tuning of the MS surface was performed to achieve strong adhesion between composite phases.The surface functionalities of MS powders were evaluated via infrared spectroscopy and scanning electron microscopy(SEM)images.Composite samples were prepared by melt-compounding followed by injection molding techniques.It was confirmed by morphological analysis that relatively better adhesion between the phases was achieved for composites involving surface-modified MS compared to unmodified MS.Tensile strength and Young’s modulus of surface-modified MS-filled composites were found to be higher than those of unmodified MS,whereas the elongation at break shifted to lower values with MS inclusions.The shore hardness of TPU was remarkably improved after being incorporated with silane-treated MS(AS-MS).Stearic acid-treated MS(ST-MS)additions resulted in an enhancement in the thermal stability of the composites.Thermo-mechanical analysis showed that the storage moduli of composites were higher than those of unfilled TPU.ST-MS additions led to an increase in the characteristic glass transition temperature of TPU.Melt flow index(MFI)of neat TPU was highly improved after MS loading regardless of modification type.According to the wear test,surface modification of MS displayed a positive effect on the wear resistance of TPU.As the water absorption data of the composites were evaluated,the TPU/AS-MS composite yielded the lowest water absorption.The silane layer on MS inclusion promoted water repellency of composites due to the hydrophobicity of silane.The results of the biodegradation investigation demonstrated that adding unmodified and/or modified MS to the TPU matrix increased the biodegradation rate.The test results at the end of a 7-week period of biodegradation with a soft-rot fungus implied that the composite materials were more biodegradable than pure TPU.Silane modification of MS exhibited better performance in terms of the characterized properties of TPU-based composites.