CN1260002C - Process for preparing porous clay isomeric material - Google Patents

Process for preparing porous clay isomeric material Download PDF

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CN1260002C
CN1260002C CN 200310122775 CN200310122775A CN1260002C CN 1260002 C CN1260002 C CN 1260002C CN 200310122775 CN200310122775 CN 200310122775 CN 200310122775 A CN200310122775 A CN 200310122775A CN 1260002 C CN1260002 C CN 1260002C
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organobentonite
surfactant
organic
bentonite
solid
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CN1554475A (en
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朱利中
田森林
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Zhejiang University ZJU
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Zhejiang University ZJU
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Abstract

The present invention discloses a method for preparing a porous clay material, which has the process that firstly, organic bentonite which is dehydrated and discarded is mixed and reacts with a co-surfactant; a neutrality inorganic precursor is added in for stirring reaction, and then solid and liquid are separated; a solid part is roasted so that a surfactant and an adsorbed organic dyed substance are removed, and then a required porous clay isomerization material can be obtained. A cationic surfactant in a normal compound method and a clay reaction step are unnecessary, and the additional cationic surfactant is unnecessary; the porous clay isomerization material prepared by the method conforms to the characteristics of the same type material prepared by a conventional method. Thereby, the present invention has the advantages of large specific surface area, uniform pore distribution and high gap ordered degree; the hole diameter is between a micro pore and a mesopore; because the material adopts wastes with low cost as raw materials, and the cationic surfactant is unnecessary, the compounded cost can be greatly reduced and the preparation step is simplified.

Description

A kind of adobe isomery preparation methods
Technical field
The invention belongs to the inorganic porous material technical field, be specifically related to a kind of adobe isomery preparation methods, particularly with the organobentonite after the treatment of Organic Wastewater as main body clay raw material and provide cationic surfactant to prepare the method for adobe material.
Background technology
MCM-41, MCM48, FSM-16 and HMS etc. are one of research focuses in multidisciplinary fields such as chemistry, physics, material and environmental protection in the world in recent years for the mesoporous material of representative; (Nature such as nineteen ninety-five Galameau; 1995; 374 (6): 529~531) reported first one class have (mesoporous material in 1.4~2.2nm) apertures, i.e. the adobe isomery material (PCHs) of having of good thermal stability from the super large micropore to the mesopore scope.This type of material is the same with other mesopore material, has that large aperture and aperture homogeneous can be regulated, an advantage such as space degree of order height, specific area are big, but also has better mechanical stability, hydrothermal stability.Adobe material synthetic adopted that to be different from conventional mesoporous material be template with the supramolecular structure that surfactant forms, utilize the sol-gel chemical process, route of synthesis by the interface directional guide effect assembling between organic matter-inorganic matter, in the interlayer duct of 2: 1 type layered clay minerals, carry out interlayer hydrolysis and condensation polymerization and be based on the organic cation and the neutral amine that enter the interlayer duct as the neutral inorganic precursor of cosurfactant template-directed, remove surfactant through roasting then, obtain the adobe material at last.Main preparation process is:
1) reaction of cationic surfactant and layered clay mineral generates organoclay composites;
2) organoclay composites and cosurfactant reaction;
3) with neutral inorganic precursor reaction;
4) surfactant is removed in roasting.
Research to this material at present mainly concentrates on aspects such as synthesis condition (material rate, surfactant and cosurfactant kind and ratio, reaction condition, sintering temperature etc.), structural characterization, absorption property, catalytic performance.But problems such as the more massive optimization of synthesizing and using also necessary solution synthetic technological condition, raw material source and cost.If can main body clay raw material and surfactant will promote the practical application of adobe isomery material well as raw material more widely with more cheap, source.
Bentonite is to be 2: 1 type layered clay minerals of typical case that essential mineral is formed with the montmorillonite, the organobentonite that forms after surfactant carries out organic modification improves tens to hundred times to organic adsorption efficiency than original soil, organobentonite since its to the excellent absorption property of organic matter, waste water (particularly organic wastewater) handle and the contaminated environment reparation in application become the focus of Environmental Science and Engineering area research.But lack cost-effective regeneration and method of disposal and remain one of subject matter of restriction organobentonite practical application in wastewater treatment.The organobentonite that has adsorbed organic pollution if can fully utilize, and not only reduces cost for wastewater treatment, and the secondary pollution that can avoid discarded adsorbent to bring.
Summary of the invention
The purpose of this invention is to provide a kind of adobe isomery material synthesis method.
With the organobentonite behind the adsorption treatment organic wastewater as synthetic main body clay raw material, add cosurfactant as the template direction agent, instruct neutral inorganic precursor between bentonite bed, to carry out interlayer hydrolysis and condensation polymerization in the duct, form inorganic-organic compound intermediate; The compound intermediate of organic and inorganic obtains adobe isomery material after surfactant is removed in roasting.
The concrete preparation process of adobe isomery material is as follows:
1) with the organobentonite behind the adsorption treatment organic wastewater through Separation of Solid and Liquid, in air, dry, 50~100 ℃ of drying 12~24h are to remove ADSORPTION STATE moisture then;
2) with dried organobentonite and cosurfactant by organobentonite: cosurfactant=1: 0.5~mass ratio mixed in 1: 2, in 20~80 ℃ of stirring reaction 15~60min;
3) at room temperature, by organobentonite: neutral inorganic precursor (mass ratio)=1: 100~1: 200 slowly splashes into neutral inorganic precursor, stirring reaction 2~8h;
4) Separation of Solid and Liquid need not washing, and solid portion dries under the room temperature in air, obtains inorganic-organic compound intermediate;
5) under air atmosphere, be warming up to 500~750 ℃ with 2~5 ℃/min speed, roasting 5~10h is to remove the organic pollution of surfactant and absorption.
Cosurfactant can be from chemical formula in the said method CNH N-1NH 2A kind of in the neutral amine of (n is a carbon number, and the n scope is 6~18), neutral inorganic precursor is a kind of in methyl silicate, ethyl orthosilicate, positive silicic acid propyl ester, the butyl silicate.Organobentonite is that a kind of and bentonite of quaternary or alkyl pyridine type cationic surfactant reacts the organic clay that obtains.
The adobe isomery material specific area of the present invention's preparation is 400~900m 2/ g, pore volume are 0.1~0.5cm 3/ g, average pore size 13~30nm, at least 750 ℃ of thermal stable temperatures, the benzene saturated adsorption capacity is (25 ℃ of 0.2~0.7g/g, benzene relative pressure 0.5 during adsorption equilibrium), carbon tetrachloride saturated adsorption capacity 0.3~0.8g/g (25 ℃, carbon tetrachloride relative pressure 0.5 during adsorption equilibrium).The adobe isomery material of the present invention's preparation is particularly suitable for the adsorbing separation of volatile organic matter (VOCs).
Advantage of the present invention is:
1) adopts wide material sources, extremely cheap discarded organobentonite as raw material, and need not additionally to add cationic surfactant, reduced the preparation cost of material;
2) preparation process is simplified, and has saved the organoclay composites synthesis technique;
3) wastewater treatment bentonite comprehensive utilization can make full use of bentonite resource, reduces cost for wastewater treatment, avoids secondary pollution, thereby promotes the application of organobentonite in wastewater treatment.
The specific embodiment
The invention will be further elaborated below by embodiment:
Embodiment 1, organobentonite (being called for short the CTMAB bentonite) in the bentonitic ratio preparation of 0.1mol softex kw/100g at first is used for the waste water that adsorption treatment contains 1000mg/L p-nitrophenol (PNP), the bentonitic saturated adsorption capacity of CTMAB is 96mgPNP/g, Separation of Solid and Liquid, the CTMAB bentonite (PNP-CTMAB bentonite) of absorption behind the p-nitrophenol dries in air, then under air atmosphere in 80 ℃ of dry 24h.Get the 14gDNP-CTMAB bentonite and mix with the 13g lauryl amine, 50 ℃ of stirring reaction 30min slowly drip the 120ml ethyl orthosilicate, dropwise back stirring at room reaction 4h.Separation of Solid and Liquid, solid portion dries, and under air atmosphere, is warming up to 560 ℃ with 3 ℃/min speed at last, and roasting 6h can obtain adobe isomery material with the organic pollution of removing surfactant and absorption.
The main character index of sample: specific area is 660m 2/ g, pore volume are 0.25cm 3/ g, average pore size 24nm, at least 750 ℃ of thermal stable temperatures, benzene saturated adsorption capacity are 0.35g/g (25 ℃, benzene relative pressure 0.5 during adsorption equilibrium), carbon tetrachloride saturated adsorption capacity 0.50g/g (25 ℃, carbon tetrachloride relative pressure 0.5 during adsorption equilibrium).
Embodiment 2, organobentonite (being called for short the CPC bentonite) in the bentonitic ratio preparation of 0.1mol chloro-hexadecane yl pyridines/100g at first is used for the waste water that adsorption treatment contains 1000mg/L p-nitrophenol (PNP), the bentonitic saturated adsorption capacity of CPC is 94mgPNP/g, Separation of Solid and Liquid, the CPC bentonite (PNP-CPC bentonite) of absorption behind the p-nitrophenol dries in air, then under air atmosphere in 80 ℃ of dry 24h.Get the 14gDNP-CPC bentonite and mix with the 13g lauryl amine, 50 ℃ of stirring reaction 30min slowly drip the 120ml ethyl orthosilicate, dropwise back stirring at room reaction 4h.Separation of Solid and Liquid, solid portion dries, and under air atmosphere, is warming up to 560 ℃ with 3 ℃/min speed at last, and roasting 6h can obtain adobe isomery material with the organic pollution of removing surfactant and absorption.
The main character index of sample: specific area is 550m 2/ g, pore volume are 0.23cm 3/ g, average pore size 22nm, at least 750 ℃ of thermal stable temperatures, benzene saturated adsorption capacity are 0.25g/g (25 ℃, benzene relative pressure 0.5 during adsorption equilibrium), carbon tetrachloride saturated adsorption capacity 0.45g/g (25 ℃, carbon tetrachloride relative pressure 0.5 during adsorption equilibrium).
Embodiment 3, organobentonite (being called for short the CTMAB bentonite) in the bentonitic ratio preparation of 0.1mol softex kw/100g at first is used for the waste water that adsorption treatment contains 1000mg/L p-nitrophenol (PNP), the bentonitic saturated adsorption capacity of CTMAB is 96mgPNP/g, Separation of Solid and Liquid, the CTMAB bentonite (PNP-CTMAB bentonite) of absorption behind the p-nitrophenol dries in air, then under air atmosphere in 80 ℃ of dry 24h.Get the 14gDNP-CTMAB bentonite and mix with the 28g lauryl amine, 50 ℃ of stirring reaction 30min slowly drip the 120ml ethyl orthosilicate, dropwise back stirring at room reaction 4h.Separation of Solid and Liquid, solid portion dries, and under air atmosphere, is warming up to 560 ℃ with 3 ℃/min speed at last, and roasting 6h can obtain adobe isomery material with the organic pollution of removing surfactant and absorption.
The main character index of sample: specific area is 680m 2/ g, pore volume are 0.26cm 3/ g, average pore size 24nm, at least 750 ℃ of thermal stable temperatures, benzene saturated adsorption capacity are 0.42g/g (25 ℃, benzene relative pressure 0.5 during adsorption equilibrium), carbon tetrachloride saturated adsorption capacity 0.55g/g (25 ℃, carbon tetrachloride relative pressure 0.5 during adsorption equilibrium).
Embodiment 4, organobentonite (being called for short the CTMAB bentonite) in the bentonitic ratio preparation of 0.1mol softex kw/100g at first is used for the waste water that adsorption treatment contains 1000mg/L p-nitrophenol (PNP), the bentonitic saturated adsorption capacity of CTMAB is 96mgPNP/g, Separation of Solid and Liquid, the CTMAB bentonite (PNP-CTMAB bentonite) of absorption behind the p-nitrophenol dries in air, then under air atmosphere in 80 ℃ of dry 24h.Get the 14gDNP-CTMAB bentonite and mix with the 13g lauryl amine, 50 ℃ of stirring reaction 30min slowly drip the 200ml ethyl orthosilicate, dropwise back stirring at room reaction 4h.Separation of Solid and Liquid, solid portion dries, and under air atmosphere, is warming up to 560 ℃ with 3 ℃/min speed at last, and roasting 6h can obtain adobe isomery material with the organic pollution of removing surfactant and absorption.
The main character index of sample: specific area is 680m 2/ g, pore volume are 0.28cm 3/ g, average pore size 24nm, at least 750 ℃ of thermal stable temperatures, benzene saturated adsorption capacity are 0.46g/g (25 ℃, benzene relative pressure 0.5 during adsorption equilibrium), carbon tetrachloride saturated adsorption capacity 0.62g/g (25 ℃, carbon tetrachloride relative pressure 0.5 during adsorption equilibrium).
Embodiment 5, organobentonite (being called for short the CTMAB bentonite) in the bentonitic ratio preparation of 0.1mol softex kw/100g at first is used for the waste water that adsorption treatment contains 1000mg/L p-nitrophenol (PNP), the bentonitic saturated adsorption capacity of CTMAB is 96mgPNP/g, Separation of Solid and Liquid, the CTMAB bentonite (PNP-CTMAB bentonite) of absorption behind the p-nitrophenol dries in air, then under air atmosphere in 80 ℃ of dry 24h.Get the 14gDNP-CTMAB bentonite and mix with the 13g n-hexylamine, 50 ℃ of stirring reaction 30min slowly drip the 120ml ethyl orthosilicate, dropwise back stirring at room reaction 4h.Separation of Solid and Liquid, solid portion dries, and under air atmosphere, is warming up to 560 ℃ with 3 ℃/min speed at last, and roasting 6h can obtain adobe isomery material with the organic pollution of removing surfactant and absorption.
The main character index of sample: specific area is 510m 2/ g, pore volume are 0.19cm 3/ g, average pore size 21nm, at least 750 ℃ of thermal stable temperatures, benzene saturated adsorption capacity are 0.31g/g (25 ℃, benzene relative pressure 0.5 during adsorption equilibrium), carbon tetrachloride saturated adsorption capacity 0.39g/g (25 ℃, carbon tetrachloride relative pressure 0.5 during adsorption equilibrium).
Embodiment 6, organobentonite (being called for short the CTMAB bentonite) in the bentonitic ratio preparation of 0.1mol softex kw/100g at first is used for the waste water that adsorption treatment contains 1000mg/L p-nitrophenol (PNP), the bentonitic saturated adsorption capacity of CTMAB is 96mgPNP/g, Separation of Solid and Liquid, the CTMAB bentonite (PNP-CTMAB bentonite) of absorption behind the p-nitrophenol dries in air, then under air atmosphere in 80 ℃ of dry 24h.Get the 14gDNP-CTMAB bentonite and mix with the 13g lauryl amine, 50 ℃ of stirring reaction 30min slowly drip the 120ml ethyl orthosilicate, dropwise back stirring at room reaction 4h.Separation of Solid and Liquid, solid portion dries, and under air atmosphere, is warming up to 700 ℃ with 3 ℃/min speed at last, and roasting 6h can obtain adobe isomery material with the organic pollution of removing surfactant and absorption.
The main character index of sample: specific area is 600m 2/ g, pore volume are 0.24cm 3/ g, average pore size 23nm, at least 750 ℃ of thermal stable temperatures, benzene saturated adsorption capacity are 0.33g/g (25 ℃, benzene relative pressure 0.5 during adsorption equilibrium), carbon tetrachloride saturated adsorption capacity 0.47g/g (25 ℃, carbon tetrachloride relative pressure 0.5 during adsorption equilibrium).
Embodiment 7, organobentonite (being called for short the CTMAB bentonite) in the bentonitic ratio preparation of 0.1mol softex kw/100g at first is used for the waste water that adsorption treatment contains 1000mg/L p-nitrophenol (PNP), the bentonitic saturated adsorption capacity of CTMAB is 96mgPNP/g, Separation of Solid and Liquid, the CTMAB bentonite (PNP-CTMAB bentonite) of absorption behind the p-nitrophenol dries in air, then under air atmosphere in 80 ℃ of dry 24h.Get the 14gDNP-CTMAB bentonite and mix with the 13g lauryl amine, 50 ℃ of stirring reaction 30min slowly drip the 120ml butyl silicate, dropwise back stirring at room reaction 4h.Separation of Solid and Liquid, solid portion dries, and under air atmosphere, is warming up to 560 ℃ with 3 ℃/min speed at last, and roasting 6h can obtain adobe isomery material with the organic pollution of removing surfactant and absorption.
The main character index of sample: specific area is 560m 2/ g, pore volume are 0.22cm 3/ g, average pore size 25nm, at least 750 ℃ of thermal stable temperatures, benzene saturated adsorption capacity are 0.30g/g (25 ℃, benzene relative pressure 0.5 during adsorption equilibrium), carbon tetrachloride saturated adsorption capacity 0.42g/g (25 ℃, carbon tetrachloride relative pressure 0.5 during adsorption equilibrium).

Claims (5)

1. adobe isomery material synthesis method, it is characterized in that with the organobentonite behind the adsorption treatment organic wastewater as synthetic main body clay raw material, add cosurfactant as the template direction agent, instruct neutral inorganic precursor between bentonite bed, to carry out interlayer hydrolysis and condensation polymerization in the duct, form inorganic-organic compound intermediate; The compound intermediate of organic and inorganic obtains adobe isomery material after surfactant is removed in roasting.
2. a kind of adobe isomery material synthesis method according to claim 1 is characterized in that the concrete preparation process of said synthetic method is as follows:
1) with the organobentonite behind the adsorption treatment organic wastewater through Separation of Solid and Liquid, in air, dry, 50~100 ℃ of drying 12~24h are to remove ADSORPTION STATE moisture then;
2) with dried organobentonite and cosurfactant by organobentonite: cosurfactant=1: 0.5~mass ratio mixed in 1: 2, in 20~80 ℃ of stirring reaction 15~60min;
3) at room temperature, by organobentonite: the mass ratio of neutral inorganic precursor=1: 100~1: 200 slowly splashes into neutral inorganic precursor, stirring reaction 2~8h;
4) Separation of Solid and Liquid need not washing, and solid portion dries under the room temperature in air, obtains inorganic-organic compound intermediate;
5) under air atmosphere, be warming up to 500~750 ℃ with 2~5 ℃/min speed, roasting 5~10h is to remove the organic pollution of surfactant and absorption.
3. a kind of adobe isomery material synthesis method according to claim 1 is characterized in that said organobentonite is that a kind of and bentonite of quaternary or alkyl pyridine type cationic surfactant reacts the organic clay that obtains.
4. a kind of adobe isomery material synthesis method according to claim 1 is characterized in that said cosurfactant is formula C nH N-1NH 2Neutral amine, n is a carbon number, the n scope is 6~18.
5. a kind of adobe isomery material synthesis method according to claim 1 is characterized in that said neutral inorganic precursor is a kind of in methyl silicate, ethyl orthosilicate, positive silicic acid propyl ester, the butyl silicate.
CN 200310122775 2003-12-19 2003-12-19 Process for preparing porous clay isomeric material Expired - Lifetime CN1260002C (en)

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Publication number Priority date Publication date Assignee Title
CN101104525B (en) * 2007-08-06 2010-05-26 浙江大学 Method for preparing anatase type bentonite-base porous titanium dioxide nano material
CN102908993A (en) * 2012-10-25 2013-02-06 常州大学 Preparation method of porous adsorbent
CN103657594B (en) * 2013-11-19 2015-07-15 浙江大学 Preparation method of tiny hole type multihole clay heterogeneous material
KR102431511B1 (en) * 2016-07-01 2022-08-12 인제비티 사우스 캐롤라이나, 엘엘씨 Method for enhancing volumetric capacity in gas storage and release systems
CN112337427B (en) * 2020-10-15 2022-07-19 四川轻化工大学 La @ Zr @ SiO2Preparation method of @ bentonite composite phosphorus removal adsorbent
CN112657460A (en) * 2020-11-04 2021-04-16 浙江工商大学 Porous clay-based adsorption material for adsorbing polycyclic aromatic hydrocarbons in atmosphere, and preparation and application thereof

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