Stody On Solid-phase Decomposition Of Ammonium Chloride

In recent years,the output of ammonium chloride in China has been continuously increasing.Ammonium chloride is mainly used in agriculture,however,ammonium chloride used as a chemical fertilizer will influence the soil and crops to a certain extent.This results in a large excess of ammonium chloride.There are some disadvantages in the above-mentioned ammonium chloride conversion technology,which have not been applied to industrial production.Therefore,it is of great practical significance to study the conversion technology of ammonium chloride.The subject has the advantages of simple process,low cost,and no pollution to the environment by using a cheap and easily available calcium carbonate reaction with ammonium chloridein solid phase,and meets the requirements of the development of green chemistry.In this paper,through the laboratory research,the feasibility of the process in different experimental devices was investigated and the following conclusions were obtained:With the muffle furnace as experimental device,the molar ratio of the raw materials was investigated through a single-factor experiment under the reaction time of 2 h.The reaction temperature was used to thermally decompose ammonium chloride to produce ammonia by high-temperature solid-phase decomposition of calcium carbonate.Through experiments,the optimum technological conditions were as follows:When the reaction material ratio was n?Ca CO₃?:n?NH₄Cl?=2.8 and the reaction temperature was 340°C,the ammonium chloride decomposition rate reached 96.1%,and the resulting solid phase product was calcium chloride.When the experimental device is a self-made rotary drum solid-phase reactor,the molar ratio of raw materials,reaction temperature,and reaction time were investigated through single-factor experiments.Through the experiment,the best process conditions were obtained as follows:reaction material ratio is n?Ca CO₃?:n?NH₄Cl?=2.6,reaction time is 1h,reaction temperature is 335°C,ammonium chloride decomposition rate reaches 93%.The solid phase product was calcium chloride.The composition of decomposition products under different conditions was characterized by XRD,SEM and the rmogravimetric analysis.