Preparation And Performance Exploration Of New Composite Titanium-based Coagulant

Titanium-based coagulants have gradually become a new type of water treatment agent due to their excellent turbidity and decolorization performance and safety and non-toxicity.In this study,three kinds of new titanium-based composite coagulants(polymerized titanium aluminum chloride,polyferric chloride ferrotitanium and ferrotitanium-based dry gel)were prepared by combining different titanium tetrachloride coagulants by different methods.Coagulant),optimize its synthesis conditions,investigate its treatment effect on surface water,domestic sewage and industrial wastewater,and explore its coagulation mechanism.The study found:In this study,the Ti salt and A1 salt,Ti salt and Fe salt were compounded by pre-hydrolysis copolymerization in ice water bath,and the polymerization of titanium chloride aluminum inorganic composite coagulant(PTAC)and polymeric titanium iron nitride inorganic composite was successfully prepared.Coagulant(PTFC).The key synthetic parameters such as alkalinity(B value)and titanium-aluminum/iron molar ratio(Ti/Al,Ti/Fe)were optimized.Two kinds of new composite titanium-based mixtures were investigated by using titanium chloride(PTC)as a control.The coagulation effect of the coagulant on kaolin-HA simulated water sample,dispersed red 1 simulated water sample and bathing wastewater,and the effect of dosage and initial pH on coagulation effect was investigated.Compared with PTC,the composite coagulant PTAC and PTFC have a lower co-agulation effect,lower dosage,and can function in a wider pH range.At the same time,the titanium-based composite coagulant prepared by the pre-hydrolysis method of the ice water bath is also longer in storage time than the PTC,and the preparation cost is also lower.Titanium-iron-based dry gel composite coagulant(TXFC)was prepared by sol-gel method.By adding hydrolysis inhibitor,the hydrolysis process was inhibited while reducing the amount of titanium salt,and the coagulation of titanium-based coagulant was overcome.The effluent pH is too low,and the coagulant prepared by the method is in a solid form,which is convenient for transportation and storage.Compared with titanium-based dry gel coagulant(TXC),the composite coagulant TXFC can achieve better coagulation treatment effect on different water bodies and different water body pH ranges.Fourier transform infrared spectroscopy and scanning electron microscopy analys of three coagulants showed that PTAC and PTFC were mainly linked by hydroxyl groups,while TXFC was linked by organic groups such as double bonds in the enol isomer.All of the three coagulants exhibited M-OH groups that promote coagulation.