Sodium sulfide

About: Sodium sulfide is a research topic. Over the lifetime, 2851 publications have been published within this topic receiving 27733 citations. The topic is also known as: disodium sulfide.

Process method for synthesizing 1, 2-benzisothiazdin-3-ketone

Abstract: The invention relates to a process method for synthesizing 1, 2-benzisothiazdin-3-ketone, which includes the steps: 1 enabling 2-chlorobenzonitrile and anhydrous sodium sulfide to react, and then performing acidification to obtain o-mercaptobenzonitrile; and 2 enabling the o-mercaptobenzonitrile to react with chlorine and water, cooling, crystallizing and obtaining target products. The process method adopts a 1, 2-benzisothiazdin-3-ketone synthesis method which is completely different from a traditional way, thereby greatly simplifying synthesis steps, lowering cost and reducing environment pollution simultaneously.

A preparing method of a battery having cobalt-nickel sulfide positive and negative electrodes, and applications of the battery in alkaline recyclable batteries

Abstract: A preparing method of a battery having cobalt-nickel sulfide positive and negative electrodes, and applications of the battery in alkaline recyclable batteries are disclosed. Firstly, a cobalt-nickel precursor is prepared through a hydrothermal process by adopting nickel foam as a substrate, adopting nickel chloride and cobalt chloride as a nickel source and a cobalt source and by adopting urea as a precipitant; then the cobalt-nickel precursor is sulfurized through a hydrothermal process by adopting sodium sulfide as a sulfurizing agent to obtain a cobalt-nickel sulfide/nickel foam positive electrode; and the obtained material is a nanotube array uniformly grew on the nickel foam substrate. A cobalt-nickel sulfide/electrically conductive carbon cloth negative electrode is prepared by the abovementioned steps except that the substrate is changed into an electrically conductive carbon cloth, and the cobalt-nickel sulfide negative electrode is a nanorod array uniformly grew on the electrically conductive carbon cloth. The positive electrode, the negative electrode and a KOH electrolyte having a concentration of 1 M can form an alkaline recyclable battery, the potential window of the alkaline recyclable battery is 1.6 V, and the maximum energy density and power density during constant-current charging and discharging in the potential window can be 27.2 Wh/kg and 1200 W/kg respectively.

Neutral Protease Assisted Low-sulfide Hair-save Unhairing Based on pH-sensitivity of Enzyme

Abstract: The mass transfer of protease in hide during enzymaticunhairing was first investigated by fluorescent tracer technique.It was found that the penetration rate of protease in hide wasquite slow, and protease remained on the grain/papillary layereven after removal of hair, which is the main reason whyenzymatic unhairing may cause grain damage or loose grain.But protease could effectively remove epidermis in a short time.From these phenomena, we developed an enzyme assisted lowsulfidehair-save unhairing (EALS unhairing) based onpH-sensitivity of neutral protease activity. To avoid risk of hidedamage, soaked cattle hide (pH 8) was first treated with neutralprotease (20 units/g hide) for 40 min at 22oC to cleave epidermisbut not to unhair, and then 1% lime was immediately added bothfor inactivation of the neutral protease (pH>12) and for hairimmunization. Finally, the hide was completely unhaired byusing 0.8% sodium sulfide with intact hair shaft. The smartlycontrolled action of protease, as well as the synergistic effect ofprotease, lime and sulfide, ensured the complete removal of hairand epidermis with reduced offer of chemicals, and preventedpelts from defects. The crust leather processed by using EALSunhairing had a cleaner grain surface compared with that usingconventional sulfide-lime unhairing. Additionally, the physicalproperties of the leather processed with EALS unhairing werecomparable to those of conventional leather. Sulfide, total solids,suspended solids and chemical oxygen demand in the EALSunhairing effluent were markedly reduced due to a dramaticdecrease in the input of sodium sulfide and lime as well as therecovery of hair.