GB2600935A

GB2600935A - Air treatment unit

Info

Publication number: GB2600935A
Application number: GB2017783.8A
Authority: GB
Inventors: Thomas David
Original assignee: Environmental Control Coatings Ltd
Current assignee: Environmental Control Coatings Ltd
Priority date: 2020-11-11
Filing date: 2020-11-11
Publication date: 2022-05-18
Also published as: GB202017783D0; WO2022101620A2; WO2022101620A3

Abstract

A high surface area component 3 for an air-treatment unit (1, Fig. 1) comprises a solid body 15 having longitudinal channels 22 extending between first, inlet 18 and second, outlet 20 end faces. First 23 and second 24 sets of channels extending from one or more perimeter faces 26 towards an opposite side thereof. The first set orthogonally intersects the longitudinal channels, i.e. axes intersect. The second channel set tangentially intersects the longitudinal channels i.e. circumferences intersect. An optional third channel set (37 Fig. 6b) extends from a perimeter face and orthogonally intersects both the longitudinal and the second set of channels. A recess 6 is provided for a UV source. The component is photocatalyst coated using zirconium and cerium oxides and may be a right circular, triangular, elliptical, square or pentagonal cylinder and the longitudinal channels may be arranged in similar patterns. The system involves an air-treatment unit comprising a housing containing the component, a UV source, power supply and filters and fans or other flow facilitators. The housing may also have photocatalyst. May be mounted on vehicles, at roadside, buildings, wind turbines or in the exhaust of a vehicle.

Description

Air Ire tment Unit tme,nt unit, to.a housing ding said component and the hr-treatment

Field of the intftion

[11001j The present invention relates to a compon configured to receive the component and to air treatment un housing. The invention also relates to air-treatment systems uni1S. The components of the invention can be used to support phatocataiytic materials used to degrade environmental pollutants, particularly nitrogen oxides (N00, Sulfur oxides (SO), volatile organic compounds NOG), polycycbc aromatic hydrocarbons (PAH), ozone (o.,.), particuiate pollutants having a size ranging, from under 1 utn to lffum, includhig bacteria, mould, fungus and viral particles. In this respect the invention provides a method for removing toxic gases and pollutants from an environment,

2 Background to the *Invention

[00031 Several studies have recognised the detrimen effect that environmental pollution has on hymen health and the ecosystem, Earn ea th and Technology, (1 article ID a-201800$) observed that there wa prevalence of *acute eye disorders. respiratory problems, cardiovascular dice and rung and uterine cancers in residents of indus,trial areas, where the levels of end I pollutants such as particulate pollutants, sulfur dioxide (SOO, nitrogen dioxide (i On monoxide te(Th ozone (03, vdatile organic compounds (VOC), polycyciic aromatic hydrocatbo.rts (PAR) and heavy S are high [00041 Particle pollutants (commonly referred as PM) comprise a mixture of particles laving diameters in the range from under 1 pm to 10prn PitAi to Prill), which are found in air, They are significant contributors to environmentat pollutants and are linked to conditions such as pulmonary and cardiovascular diseases, lung cancer and dementia Ozone (03, sulfur dioxide (SO;) and nitrous oxides, inctuding nitrogen dioxide (NO2) are believed to be responsible for an increased risk of asthma and for damage to the eyes, skin and respiratory tract. PAHs and VOes have been associated with skin aging and the forrnadon of pigmented soots on the face. Other effects of air pollution include (thanges in white blood cell count, hypertension, .neurotogicaU complications and psychiatric disorders phoraniazam, a Res Med Sci 2006. 21(65); do i: 10,410311735-1995 189646). Other airborne species that have detrimental effects on health include pathogens such as bacteria and viruses, wh,ch can be trahSthitted via particles or droplets, particularly in enclosed spaces.

[00051 A photocatalyst is a material that helps to accelerate and enhance.a tight induced reaction without being consumed in the process In most instances the catalytic activity of the photocatalyst is dependent on each of the frequency and the intensity of the light to which the photocatalyst is exposed, The use of:photocatalysts to degrade environmental pollutants is known. .2.259 teaches silica catalysts conioncng tnanurr and zucon urn dopants for degrading volatile organic compounds (VOCs) and toxic air pollutants at UV wavelengths of *less than 400nm Photocatalysts have also been found to exhibit antibacterial and anteviral properties, Ramesh et al, Food Bioprocess Technot 11, 2242-2252 do::10 1007/s11947-018-2192-9, reported that the use cxf a titania-silice photocat reduced the light energy needed to decompose Escheriohla coli in white grape. juice The bacterium could be degraded by (MA light in the presence of the photocatalyst, but or-1/y by UVC light when the photocatalyst was absent GB 2012145,, tesehes zirconium cerium photocatalysts capable of removing toxic gases and pollutants tncwdtig particulate mafter from an environment.

[00061 Machines and vehäies powered by an internal combustion engftie a ofte r fitted catalytic convertor to reduce the concentration of toxic gases and pollutants prod le exhaust gasses, Catalytic convertors comprise a high surface area support, an adhesive and a catalyst bound to the support via the adhesive. Suitable catalytic materials include platinum, rhodium and palladium. Oxides o iricohlium are often inclut in the adhesive ts.,.1 increase the surface area of uhstrate on which the catalyst is supported, It is essential that the support stiucture has a hign surface area this has the dual function of maximising the amount of catalyst supported in the structure and the efficiency of the cata1Y9f; cicrwerskplt Furthermore. the catalytic conversion of toxic gases and pollutants requires heat and a high surface area improves heat distribution within the struc1t Examples of high surface area supports include alumina beads; metal meshes and substrates comprising surfaces defined by a triply periodic minimal surface (TPMS) as described in WO 2017/192508, The substrates of WO 2017/192508 include a plurality or cells arranged in three dimensions, Each of the plurality of unit cells includes a cavity defined by a triply per odic minimal surface tTPMS) and the cavities of the unit cells may be interconnected to allow a fluid to pass through Examples of triply periodic minimal 8 that have been used in the manufacture of cataiytic convertors include a Schwartz Piimiiive surface, a Schwarz crossed layers of parallels (CL,P). a Schoen's Gyrord surface, a Scho.en's I-WP surface, a Schwartz diamond surface. a Fischer-Kich PMY s.usfaca, a FRD surface, a Fischer-Koch CV surface, a Fischer-Koch surface or a Neovius surface. Other TPMS surfaces known to a skilled person include Diamond, Split P and Lidinold surfaces. TPMS are Often designed to create turbulent flow through the structure to increase residence time of exhaust gases in the convertor and maximise their conversion to less harmful substances This is ideal in situations where the conversion reaction requires heat but is unsuitable for conversion reactions that are light catalysed as the TPMS structure tends to impede the transmission of light through 71 A need exists for a component comprising a high surface area support tt capable of supporting a photocatalyst and Mitch facilitates the effective transmis ughout the component body without a significant loss of intensity. The present v addresses those needs, In a first aspect.of the invention there is provided a component for treatment unit: the component comprising a photocatalybc material and a solid tx3dy, the olid body comprising: ed b; :a first e.nd including a first end face, an outlet second n including a second end face and one or more perimeter walls defining one or more perimeter faces extending between the first end and the second end: a plurality of longitudinal channels extending through the body from the first end the second end face longitudinal channels defining a longitudinal Urection for the flow of air t. h the body, the channels extending substantial y llel to each other along the longitudinal direction cvert least part of the length of the set of channels comprisng a plurailtyrows,channels provided at one of the perimeter walls, said FOWS extending laterally and being aligned in a longitudinal direction over the or each perimeter wall each of the channels of the ret set extending radian') from e Perimeter face of the at least one perimeter wails through the body towards an opposite side of the bedy in a direction substantially perpendicular to the direction of the longitudinal channels each c.hannal of the first set of channels being configured to orthogonally intersect one or more adjacent channels in a radially extending row of longitudinal channels, the row of longitudinal channels extending in a direction substantially parallel to the or colon in which the channels of the first set extende a second set of channels provided over at least one of the perimeter walls and comprising a plurality of rows of channels, said rows extending laterally and being aligned in a longitudinal. direction over a pebmeter.ftce of the at least one perimeter walls, each channel of said second set extending perimeter face of the at least one perimeter walls through the body in a direction substapt perpendicular fo. the direction of the longitudinal channels: eadh of the rows second set of channels being dispersed between the rows of the first as channels and laterally off-set therefrom: each channel of the second set being configured to tangentially intersact two laterally adjacent radially extending rows Ct longitudinal channels, the rows of longitudinal channels extending in a direction substantially parallel to th direction i.n which the channels of the first set extend, the first set of channels, second set of channels and perimeter wail defining a substantially continuous surface having a ohotocatalytic material supported thereon: and e. a recess for receiving a UV light source within the body 100091 The solid body may 'ASO COT:prise a third set of channels, each channels of the third *set of channels efrigI configured to orthogorially intersect both one Of more *iongitudinal*channels and one or more channels, from the second set of channels, Preferably the point at which each channel from the third set orthogonaily intersects a longitudinal channel is offset from the point at which the respective channel of the third set orthogonally intersects a channel from the second set of channels. Preferably the offset is lateral or radial, depending on the configurabon of the lonoltudinal channels.

0010] By the term "component for an air-treatment system" it should be understood to mean a device that, when installed into an air-treatment unit in an air-treatment system, is able to remove toxic gases or pollutants such as those referred to above from an environment such as the interior of a budding or a vehicle, a roadside, an airport a railway station, a marine port or a vehicle exhaust system outlet, The term "remove" includes retention of the toxic species or pollutants in an unaltered, tom, within the component as well as conversion of the toxic gases or pollutants to a less harmful form that is not damaging to the ecosystem.

(0011] By the tern ''air-trea:ment unit it is to be understood to mean a component according to the first aspect of the invention together with the housing into which it is received, pal 21 By the term 'air-treatment system' it is to be understood to mean a system including an air-treatment unit 100133 By the term 'toxic gases and poilutante It should be understood to mean nitrogen oxides (NO,). sulfur oxides (SCA volatile organic compounds (VOG) oolycyclic aromatic hydrocarbons (PAH), ozone (0.3), particulate pollutants having a size ranging from under ipm to 1 Oum, including bacteria and viral particles.

[00143 By the term 'orthogonal intersection-it should be understood to mean that any one channel of the first set of channels passes directly through a respective longitudinal channel in a substantially perpendicular direction such that a central axis defining the direction of any one of the longitudinal axis intersects with or cross.es a central axis defining the dire:Aion of any one of channels from the first set with which it is configured to intersect in a substantially perpendicular fashion (00151 By the term langentiai intersection' it should be understood to mean that any one channel of the second set of channels merges with a one or more longitudinal channels at their respective circumferences, such that a central axis defining the direction of any one of the longitudinal channels s oerpandicu axis defining the direction of any of hannels from te second set, but does not intersect there with: instead the perpendicularly extending axes are spatiaRi offset from each other. Tangential intersection could further be defined lay the perpendicular intersection of an arc defined by the circumference of the longitudinal channel with an aro defined by the circumference of one of the second set of channels, 10015] By the term 'substantially peroendicular" ft snoula be urdoi stood to mean that each of the first set of channels. intersects the longitudinal cha of between 90 and 109', preferably at an angle of between 90 and 102.more preferably, at an anqi ween 90 to 95' and especially at an angle of between 90 and 921. The term should also interpreted in relation to the relative orientation of the second set of channels This each of the second set of channels exterids at an angle of between 90 and 109. preferably at an f between 9Gt and 102, more preferably. at an angle of between 90 t95 and especially at an angle of between 90 and 92 relative to the longitudmal channels loom By the term "longitudinal direc,tion" it is to he understood to mean a direction defined between the first and second end faces of the body, This is typically the largest dimension of the body t00181 By the term longi'udirial axis of the body or-centi al axis of the body'it siould no understood to mean an artificial line passing through of each ot the first and second end faces and extendinc) there between 100191 By the term lateral direction", 'extending laterally' or hextending cucunfeientia9yc it should be understood to mean a direction which follows a Inc Or part of a ft is defining the per meter r circumference of the body, Generally this direction is also substantially perpendicular to the longitudinal axis of the body, For example, where the body is a right square cylinder, the lateral direction extends across all the perimeter walls. Where the body is a circular cylinder, the tat direction extends around the circumference of the cylinder, [0£1201 By the term laterall adjacent it snould be untleistood to mean next to each other in a laterci direction.

(00211 By the term it should be undorstoed to mean next to each other in a direction extending from a perimeter face on one side of the body towards the opposite side of the body. Where the body comprises a square array of longitudinal channels, two channels would be considered radially adjacent if they were next to each other in a direction extending from one perimeter viva to the opposite perimeter wall. Where the body COMprises a circular array of longitudinal channels, two channels would be considered radially adjacent W were next to each other in a direction extending from one penmeter face towards the lo itudinal axis of the body in this respect it should be understood that the terms "radialiy extending' and ending radially' mean a direction ódendingfra.rn the petmSter ffice of a perimeter wall through the body towards an opposite perimeterface of an opposite towards thefl opposite side of the body, 100221 The solid body in which the channels are contained is characterised by one o more perimeter faces extending over the one or more respective perimeter walls, the one or MOre, perimeter faces being defined by an exterior surface area. Each of the longitudinal channels and the first and second and optionally third sets of channels together are interlinked to define an Internal surface within the solid body, the internal surface being defined by an nmaE surface area and an inte.,mal volume for containing air passing through the body, The iongitudinat channels terminate at each of the first and second end faces. The first and second sets of channels are terminated at the one or more perimeter faces of the body. The third set of channels extends through the body Depending on the configuration of the longitudinal channels, the third set of channels may terminate at a perimeter face. Where third set of channels terminates at a perimeter face, It terminates at a perimeter face orthogonal the perimeter face at which the second set of channels terminate. Together, the longitudinal channels and the first, second and optionally third set of channels and the Perimeter feces define a continuous surface having a total surface area characteristic of the configuration of the body, The body may aiso be defined in terms of the ratio of its surface area to internal air volume, the internal air volume being the volume occupied by the longitudinal. first and second set of channels within the body The body is suitably defined by a total surface area to internal air volume in the range of 0,4 to 0.8. Preferably the ratio of the Isurface area to internal air volume is in the range 0 45 to 0,75 and is especially 048 [ 2] The photocatalytio material may be supported on the substantially continuous surface as a coating, such as via an adhesive or other suitable binder Alternatively, it may comprise an integral part of the surface Suitably. the photocatalytic material comprises a mixture of zirconium and cerium oxides Preferably the photocatalytic material comprises 85 to 99.5 mot% zirconium oxide and 0,5 to I 5tnol% cerium oxide The zirconium oxide preferably comprises a zirconium (IV) oxide, The cerium oxide preferably comprises a mixture of cerium OW oxide and cerium (IV) oxide-Preferably the photo -catalytic material is a material of the type disclosed in United Kingdom Patent application GB 2012145.5. Alternatively. or in addition, the coating comprises quaternary ammoriimin polymer, silver nano-particles, copper nano-particles, gold nano-particles and particles of oxides of metals of Thon tin zinc and titanium.

(0024j The solid body in which the channels contained suitbly comprises materials selected from the group comprising a polyamidie, a ceramic, a metal including a metal allay. The solid body may be derived from any.suitabie. Shape,such as a cuboid, a cylinder, a sailers or a cone but is Prefereb/Y in the form of a cylinder i Ely the term 'cylinder" it should be understood to include a circular cylinder, an elliptic cylinder. a square cylinder, a* rectangular cylinder, a triangular cylinder, a pentagonal cylinder, a hexagonal cylinder or the like. Each cylinder is characterised by first and second end faces and one or more perimeter walls extending from and between the or each respective edge or edges of the first and second end faces Suitably, tne one or more perimeter walla extend in a direction that is substantially parallel with the longitudinal axis of -the body 10025) Inc solid body including the channels can be forMed from any suitable methods known to a skilled person. Suitably, the body can be moulded using techniques known to a person Skilled in the art. Methods such as those disclosed in WO 2017,192508 can also be employed. Alternatively, the body can be manufactured using three-dimensional printing techniques (3D printing).

100261 Where the body is a cylinder the longitudinal channels extend through the body between the first end face and the second end face of the cylinder. The longitudinal channels are preferably proideci in the form of an array extending over each of the first and second end faces, Preferabiy each longitudinal channel in the array is aligned with at least one other longitudinal channel in the array. A central axis defined by each longitudinal channel may be parallel with a longitudinal axis of the cylindrical body, Preferably tile central axis of each of the longitudinal channels in the array is parallel to the central axis of each of the other longitudinal channels, The array of channels is suitably configured to define a regular pattern of longitudinal channels extending across each of the first and second end faces Each end face may, therefore, be characterised by a square array of channels comprising parallel rows of channels extenoing across each of the first and second end faces. Each of the channels in one row is suitably aligned with a corresponding channelii the previous row. It will be appreciated that other arrangements of longitudinal channels are possible within the body. For example. each end face may further be characterised by an array of channels having different geometrical configurations' triangular, circular, pentagonal or hexagonal rows of channels may be arranged concentrically over each erid face. VVhere the longitudinal channels are arranged as concentric rows over each end face, the rows are also preferably aligned to also define radial rows of channels extending in a direction from the longitudinal axis of the body towards the perimeter wall It should be understood that in the context of the present invention, the term "circular row" includes l'owe of other geometric shapes for example triangular, pentagonal, hexagonal, heptagonal and octagonal rows and the like as well as circular or elliptical rows, The configuriation of the array of longitudinal channels across each end face may reflect the shape of the body containing the array. but it might also be different. For example, a right CiftUlar OyfiaddCal bOdy May ix characterised by a square array of* channels at each of the first and second end faces.

[0027] The or each perimeter face includes a first set of channels. each channel being defined by a central axis, which chanriel *and a.xis extend from the perimeter face radially through the body in a direction that is substantially perpendicular to the direction of a central axis of a lonaitudina; channel with which it is configured to intetsect. In this way a central axis definino any one of the channels of the first set of channels orthogonally intersects the central axes of one or more radially adjacent longitudinal channels The first set of channels is further characterised by an array of channels, the array comprising rows of channels extending both laterally and.iongitudinally over each perimeter face. Preferably the rows constituting the first set of channels are aligned over each perimeter face so that any one channel in a row is aligned with an adjacent channel in the preceding TOW SO that the array comprises parallel rows of channels extending laterally and longitudinally over the perirneter thoe of each perimeter wan, Preferably the central axis of each of the channeis of the first set of channels extends substanbally parallel to each of the first and second end faces of the body, In a preferred first embodiment, a longitudinally aligned row of channels of the first set of channels is configured to orthogonally intersect with one or inure channels in a respective row of radially aligned longitudinal channels [00201 One or more of the perimeter faces includes a second set of channels, each channel of said second set being defined by a central axis, which channel and axis extend radially from the perimeter face through the body in a direction that is substantially perpendicular to the direction of a central wds of a longitudinal channel with which it tangentially intersects. The second set of channels is further characterised by an array of channels, the array comprising rows of channels extending both laterally and Longitudinally over each perimeter face, Preferably the rows constituting the second set of channels are aligned so that any one channel in a row is aligned with an adjacent channel in the preceding row so that the array comprises parallel rows of channels e:xtending laterally and bngituritnaily over the perimeter face of the perimeter wall on which the second set of channels are provided Preferably the central axis of each of the channels of the second set of channels extends substantially parallel to each of the first and second end faces of The body and substantially perpendicular to the longitudinal axis of the body. In a preferred embodiment, the second set of channels comprises sets of substantially parallel longitudinal rows of channels laterally aligned over the perimeter face, each channel in the lonoitudinally aligned row of the second set of channels being configured to tangentially intersect with one or more channels in the laterally adjacent, radially extending rows of longitudinal channels, Thus, each channel of the second set of channels is characterised by an intersection with two laterally adjacent, radially extending rows of longitudinal channels between which it passes, The second set of channels may bs provided on the same perimeter face as the face bearing the first set of channels or it may be provided on a different perimeter face. Preferably the first *eel of channets and the second set of channels are provided on the same perimeter-face or faces. Where the first set of channels are provided on different perimeter faces, the first bet of channels is previced on a perimeter face that is substantially orthogonal to the perimeter face on which the second set is provided Where a perimeter face i.ncluctes a second set of channels, the periineter face is characterised by two interspersed arrays of channels which each of the rows of the array defining the second set of channets is positioned between adjacent rows of an array defining the first set of channels. Each of the rows of the second set of channels is suitably offset from the adjacent aligned rows of the first set of channels, so that each channel of the second set is essentially surrounded by four channels of the first set and vice versa [0029] The advantages of a configuration in which a perimeter face Mcludea first and second sets of channels is that it provides a continuous surface with a high eta-face area Further the configuration facilitates the efficient transmission of light ernitteid by a UV light source located in the recess throughout the oody. The component of the present invention can support extensive and efficient light catalysed conversion of toxic gases and pollutants to less harmful substances.

(0030] Where the first and second sets of channels are provlded on the same perimeter face or faces, the body may preferably further comprise a third set of channels, which extend-s throughout the body M a direction that is orthogonal to both the longitudinal channels and the second set of channels. If the longitudinal channels are provided as a square array over each of the first and second end faces, the third set of channels may be provided over a perimeter face that is orthogonal to a perimeter face on which the first and second sets of channels are provided. In such a case the channels of the third set are characterised by art array of channels, the atray comprising rows of channels extending both laterally and longitudinally over each perimeter face Preferably the rows constituting the third set of channels are aligned so that any one channel in a row is aligned with an adjacent channel in the preceding row so that the ai ray comprises parallel rows of channels extending laterally and longitudinally ove.r the perimeter face of the perimeter wall on with the third set of channels are provided. Where the longitudinal channels are provided as a circular array of Channels, the circular array comprising concentric circular rows of channels, the third set of channels extends in a direction substantially parallel to the direction of said circular rows and does not necessarily terminate at a perimeter face, [0031/ in preferred embodiment of the from a square cyhnder which comprise Said first and second end faces. The so ond sets of opposing perimeter faces a pet, the component comprises a body derivsd rray of lengitudthal channels over each of r is further characterised by first and endthg between the first end face and the a first setchannels extending between a first set of opposing faces and Gond set of channels: offset fron said first set and configured to extend between ti se pØosite faces chty.Preferably the channels of the second set are both laterally and loncjittidinally offs he channels of the first set, A component comprising a egdare array of longrtudin -a cylinder. Alternatively. it m array of channels over eac as described herein may be configured as a right square shaped or cut into a right circular cylinder having a -square he first and second end faces.

(00321 in a particularly preferred embodiment the component comprises a third set of channels extending betuyeen a second set of opposing faces of a right square cylinder, each channel of the third set being configured to orthogonally intersect one or more adjacent longitudinal channels in a row of longitudina channels d also orthogonally intersect one or more channels in a lateraflv extending row of the second set of channels, The channels within the third set of channels preferably have a diameter that is substantially the sa the diameter of the channels of 'noond set I In a fourth embodimetit of the first aspect of the vention, the solid body is configured as a circular or elliptical cylinder. Preferably, he solid body Es derived frorr circular cylinder and the longitudInal channels are configured as sets of rat tally aligned substantially circular rows of channels arranged substantially concentrically about the longitudinal axis. The longitudinal channels are also configured as rows of radial channels, the number of radial rows-corresponding to the number of longitudinal channels in any one of the circular rows of channels Preferably the diameter of each of the iongitudinat channels is uniform across the array, Alternatively, the diameter of the individual channels in an array may increase in a C ection extending from the longitudinal axis of the body towards the perimeter. This ensures, particularly for pentagonal, hexagonal, right circular cylinders and the like that the continuous surface has a high surface area.

(00341 The longitudinal channels may be characterised by a theme its length Alternatively., the diameter of one or OVe of the longitudinal dhan.nots may vary along their length as required to either improve airflow through the body orto niprove transmission; in this respect, the diameter of a longitudinal channel may decrease in a direction going from each of the end faces to.wards a centre of the body in this case the channel is characterised by a slight restriction along its length followed by an increase in the Channel diameter adjacent the outlet of the component. This has the effect of increasing residence tIme of a gas passing through the component up to the point of the constrtion and then increasing the flow of gas exiting the component via the outlet. Alternatively, diameters of the longitudinal channels may increase in a direction along the tonoitudinal of the body going from the inlet lo the outlet. In a preferred embodiment the longitudinal els am all chaiactensea by a unforrn diameter along their length. Suitably: each,af the Inal channels has a diameter in the range 3m into Imin, preferably 4rilm to amm and especially 5mm The s cing between the centres of eachthe longFtJchnal c chosen to provide a balance between ensuring the component body is suffi iently rig function as a catalyst support and providing a support surface with a sffioently high surface area to maximise the amount of photocataiyst located on or in fhe* :apiece. Suitably, the spacino between the centres of each of the longitudinal channels is in the range 5mm to it preferably 6mm to 9rnm. especially 7.5mm.

j Where the solid body is a right circular or an el s a simile perimeter face and the first set of channels exter:ds radially from th erimeter face towards the longitudinal axis of the body, each channet of the first set of channels being configured to intersect at least one ton:Audichannel in a radial row of longitudlnal is which the channel of the first set is aligned. The diameter of each channel of the first set of channels may be;.iniforrn along its length.. Alternatively the diarre1/4-1r of each channel of the first set of channels may increase in a direction extending from the longitudinal axis of the body to the pt,,-.3rimeter face This will also be true for penkgonal and hexagonal cylinders, This increase in diameter in a radial direction extending front the longitudinal axis towards the perimeter of the body also helps to maintain the hgh surface area of the continuous surface, A second set of channels is also provided over the perimeter face and each channel of the second set also extends radially in a direction from the longitudinal axis of the body to the wirneter face, each channel of the second set of nels being configured to tangentially intersect two adjacent radial rows of longitudinal channels. As before all the channels within the second set may have a uniform diameter along their length. Alternatively, the diameter of each channel of said second set may n a radial direction extending from the longitudinal axis of the body to the perimete face. Suitably, all of the channels of the first set of channels are characterised by a uniform eter along their length Where the body further comprises a third set of channels, these nets extend in a direction defined by the circular rows of longitudinal channels ',,vithin the ler array. The channels of the third set orthogonally intersect each longitudinal channel in a radial row of lOngitudinal channels. Furthermore: the third set of channels orthogonally intersects each channel of a radially extending row of channels of the second set of channels. In this respect each channel of the third set cf channels has a diameter that is substantially identica with the thameter of the than he second set a th which it intersects, [00361 Suitably, each of the channels bf the ttird set defined b. al axis, channel and axis extend through the <lion that is substantially perpendicular to both the direction of a centra axs(L) and a direction of the second "set of channels with which it intersects. Where the longitudinal channel', are provided in the form of a square the thwd set of channels are preferably charecter:sed by an array of channels, the rray comprising rows of channels extending both laterally and longitudinally over the perimeter face or faces on which Preferably the rows constituting the third set of channels are aligned so that any one channel in a row is aligned with an adjacent channe,1 in the preceding row so that the array comprises parallel rows of channels extending laterally an longitudinally over the perimeter face of the perimeter wall on I ' 1 set of channels are provided,. Preferably the central axis of each of the channels of the thirtiset of channels extends substantially parallel to each of the first and second end faces of the body and substantially Perpendicular to the longitudinal axis of the body, in a preferred embodiment, tile third set of channels comprises sets of substantially parallel longittAinal rows of channels laterally alioried over the perimeter face each channel in the longitudinally aligned row of the third set of channels being configured to orthogonally intersect with one or mor5 channels in a rectally extending row of longitudinal channels and to orthogonally intersect with one or more channels in a laterally extending row of channels ofsecond set of channels, Thus, each channel of the third set of channels is characterised by an intersection wth one or more adjacent longitudinal channel artd also with one or more channel of the second set of channels 371 Preferably, for all ernbocLments eachchannel in said first set has a diameter in the range 2rnm to emm, preferably 3mm to 5mrn and especially 4rnm. Suitably the spacing between the centre of each of the channels of said first set is in the range 5mrn to lOmm, preferably emm to 9rrim, especially 7 5mm, Suitably, all of the channels of the 'second set of channels are characterised bY a UnifOrrn diameter along their length Suitab, each channei in said second set has a diameter in the range 3mrn to 7min, preferably ztrnrn to 6mrn and. Specially 5mm Suitably, the spacing between the centre of each of the channels of said second set lain the range 5mm to larnn-t preferably emm to 9inin, especially 7,5mm, Suitably, all of the channels of the third set of channels are characterised by a uniform diameter along their length. Suitably, each channel in said third set has a diameter in the to Imm, preferably 4rnril to Smni and especially 5rnm Suitably, the spacing between the centre of each of the channels of said third set is in the range 5rnm to lOrnm.

preferably 6mm to gmin, especially 7.5mm, 100381 The recess for receiving *o UV light source is suitably located at and extends along the longitudinal axis of the body. The recess is pieferably lo.i)ated at the inlet of the body. but may also be located along the longitudinai axis of the body extending from the body outiet towards the inlet, hi an alternative arrangement, the, body* may comprise a plurality* of small recesses distributed evenly over the first end face and around the iongitudinal axis of the body each recess being configured to receive a light source such as a strip of light emitting diodes (LEDs). The body may fudher comprise a heitc.al recess extending from the first end face to the second end face the helical recess configured to receive a light source. such as stnp of LEDs.

[0039] The component:suitably ftirtner comprises an end piece configureci to be positioned at an end face distal to the recess for re.ceiVmo.a.UV light source, to prevent transmission of UV light through the distal end face. The end piece is configured to facilitate air flow through the body and as such a may be provided with baffles andlor angled channels to support atiflovv through the body vvhitst obscuring the emission of the UV light at an and face Whe.re the recess extends from the first end face. the end piece is suitably attached to the second end face and cdrnPrises PeriPherel concentdcally arranged rows of angular channels extending from the inner surface of the arid piece to the outer surface: the inner portion of the inner surface includes one or more baffles configured to direct the flow of air out of the matrix and block leakage of UV light from the body [0040] A second aspect of the invention provides a housing for receiving a component according to the first aspect of the invention, the housing cofflPdsing an inlet and an outlet: a housing we:I extending between the inlet and the outlet: the housing wail definin,g (i) an enctosure for receiving a component according to the first aspect of the invention 00 an at passage between the net and the outlet and (ill) a longitudinal direction between said inlet and said outlet for defining the flow of eir through the housing comprising and means for facilitating airflow between sad inlet and said outlet. The housing wali comprises an outer surface and an inner surface configured to face the enclosure A photocatalytc coating may be provided on the inner surface of the housrng. Alternatively or in addition the inner surface comprises a reflective matenal, A filter may also be provided on the inlet to remove particulate material having a diameter greater than 15 microns, [0041] The inner surface of the housing may be configured to improve the efficiency of the catalytic conversion or augment the airflow, throughout the air-treatment unit In addition to the coatings referred to above, the inner surface may comprise one or more recesses for receiving a source of UV light: [0042] The inner surface of the housing may be configured to control turbulent airflov,, between the housing inlet and the housing outlet. The housing may also be configured to support a UV light source for receipt into the feces Of component body accord:no to the spect of the invention, Suitably, the inner surface is characterised by an undulating Profile along the longitudinal direction of the housing. Alternatively, the inner surface is characterised by a circumferentially extending undulating profile transverse theiongitudina direction of °using. The undulating shape may be.a twisted undulating:shape.

Preferably, the inner surface comprises Cr undulating shape vvith a sinusoidal profile ha peaks extending into the enclosure and troughs adjaccnf the housing wall The toughs be configured as recesses for receiving a LlViioht source, [0043} Air-treatment units including the housing and the component of the first aspect invention may be:notched in a variety of locations, The units may suitably be installed in the exhaust system of a car lorry, ship, aircraft or other similar vehicle. Alternatively the units may be installed in shops, roadside locations airports, railway stations, ports, schools. homes, theatres, cinemas, restaurants, public houses or other pubitc buildings, The units may also be ire.egially formed with or installed on the roof or another herizontdt surface of vehicle such as a car, a train or a lorry, (0044) The housing may also comprise one or more ns to direct the flow Of air entering ound a UV light source, through and over the body. Examples of suitable etutes which direct this aif flow, include one or more baffles, s fan or an air funnel. Examples of fans that can be used in this apPlication include an axial Mn, a centrifugal fan and a cross-fiow fan. The means for facilitating the flow of air between the inlet and the outlet may be positioned at the housing inlet or at the outlet Where the unit is installed in a vehicle exhaust t a roadside location, the means for facilitating the flow of air between the inlet and the outlet is preferably positioned at the housing ouitlet. Where the Jni is installed on the roof of a vehicle the means for facilitating airflow is preferably an air funnel positioned at the housing inlet.

[0046] In one embodiment of the second asineat of the invention the housing may ho a box attached to a fixed construction such as a building or a windmill or it may be attached to vehicle, Preferably the box is integrally attached to a vehicle housing. The housing inlet comprises an air funnel for facilitating air flow, ore or more turbine components and one or more electrical generators connected to and driven by respective turbine 000iporlents thereby to power a source of UV light within the unit, in this respect the air confIured to. direct moving air over the one or more turbine units to generate ehoug.h en to drive a source of IN light, The air then passes over and through the component body received in the housing, where the toxic gases and pollutants present in the air are converted to less harmful substances, This embodiment makes use of the movement of the

IS

vehicle to power the unit to support the catalytic conversion, The roof of the vehicle may also be fitted with solar cells to power the UV light source when the vehicle is stationary.

100461 A third aspect of the invention provides an air treatment unit comprisino component according to the first aspect and a housing according to the second aspect, [00471 Further aspects of the inventiori include the use of a component according to the first aspect or an air treatment unit according to the third aspect for reducing or removing tC3.>dc gases or pollutants from an environment. Another aspect of the invention provides a method for removing toxic gasses or pollutants from art environment, said method comprising the steps of passing a composition comprising said toxic gases or pollutants over a component according to the first aspect of tne invention or through an air treatment unit according the third aspect, 00481 The invention will now be described with reference to the following non-limiting figures and drawings in which: (0049) Figure'', is a drawing of an air treatment unit comprising the component and housing of the first and second aspects of the invention (00501 Figure 2 is a drawing Of the component of the first aspect of the invention illustrating the configuration of the longitudinal channels within the body of the component.

(00513 Figures 3 and 4 illustrate alternative configurations of the longitudinal channels 'ivithin the body of the component according to the first aspect, [0052] Figures 53 and 5b illustrate a ccimponent according to the first aspect of The invention [0063) Figures 6a, 6b, 6c, 7 and 8 illustrate an alternative component according to the first aspect of the invention, 0054] Figures 9 to 12 illustrate the ways in which the longitudinal channels can be arranged over the first and second end faces.

10055] Figure 13 is a view of the component of the first aspect of the invention illustrating the intersection of the longitudinal charinels with the first set of channels, [00561 Figures 14a. 14h and 14c are a top-down views illustrating the various arrangements of the first and second sets of channels relative to the longitudinal channels [00571 Figure 15 is a iongitt.dinal cross-section through the housing of the second aspect [00583 Figure 16 is a transverse cross-section through the housing [0059] Figure 17 illustrates the helical arrangement of an LED strip light source within the component of the first aspect of the invention, 00601 Figure 18 is a longitudinal cross-section through the housing illustrating the halloo: arrangement of an LED,strip light source within the housing [0061] Figure 19 illustrates the unit according to the third aspect of the invention fitted to the roof of a car.

[00821 Figure 20 illustrates the unit according to the third aspect of the invention fitted to the bonnet of a car.

/00631 Figure 1 illustrates an air -treatment unit (1) cornprishg a housing (2) and a component (3) retained within the housing (2). In use air flows with the direction of the arrows A and kin through the inlet (4) of the housing (2), through the component (3) and housing (2) and leaves via housing cutlet (5). The component (3) includes or supports a photocatalyst on its surface and further includes a recess (6) configured to receive a UV lin. ht source (7). A fan (8) is optionally provided at one end of the housing (2) to pun air through* the component (3). in the present illustration, the fan is located at the outlet (5) Flovvever.

*the fan could equally be positioned at the inlet (4). The component (3) is retained w thin the housing through the use of positioning pins (9) and the UV light source (7) is retained Xi poSition through the use of bracket (10), which is configured for attachment to the housing (2) A control unit (11) provides power to the UV light source (7) and the fan (8) and may also be used to monitor the state of the component (3), A finer (1'2) may optionally be positioned at the inlet (4) to prevent large particles from entering the housing (2) An end piece (13) may also be provided: the end piece (13) incit.ides a baffle (14) to prevent UV light from being visible frerti the outlet (5) of the housing (2), [00641 The component (3) of the air-treatment unit (1) is illustrated in finures 2 to 14, In the embodiments illustrated in figures 5 to 8. the component (3) comprises a solid body (15), the body (15) comprising an inlet (16) comprising a first end (17) including a first end face (18) and an outlet (19) comprising a second end (20) including a second end face (21), One or more perimeter walls (25) extend between the first end face (18) and the second end face (21) Each of the perimeter Walls defines one or more perimeter faces (26, 26a, 26b, 26c). A plurality of longitudinal channels (22) extend through the body (15) from the first end face (18) to the second end face (21).

(00651 A first set of channels (23) is provided over one or MOre. perimeter faces (26, 26a, 26b). The channels of the first set (23) comprise rows of channels (23a) which extend laterally over a respective perimeter face in a direction defined by the circumference of the body (15) as illustrated by the dotted line in figures 5a, 5b, 6 and 7 Each of the channels in the row of channels (23a) is aligned with a channels in the row above so that the set of channels (23) comprises substantially parallel rows of channeis that extend both laterally (23a) and longitudinally (23b) over the perimeter face as illustrated 'by the dotted line in figures 5a, 5b, 6 and 7), Each of tile channels in the first set of channels (23) extends radially throuoh the body 05) from a first perimeter face towards an *opposite side of the body (15). Where the longitudiral c:hanna are provid d on the fi sccnd endaces as a square array (figures 5a, 5b, b and Bo) and the body is in the.tonrn afar is derived.

right square cylinder, the first set of channels extend from one perimet through the body to an opposite perimeter face. Where the longitudinal channels, provtded on the first and second end faces as a circular array and the body is provided n the form of a right circular cylinder (figures 7 and 8) the first set of channels extends from* a nieter Pace through the body towards the longitudinal axis of the body Prefer he chanhéis of the first sat of channels (23) extends in a dIrecijon tha i subtahtMHy Parallel to a Plane defining a first of second and face. in addition a radiallyenendnj tongitudina row of the first set of channels extends perpendicutar to the tongitudtnal axis (1...) of body. Furthermore each of the channels of the first set of channels (23) provided on the perimeter face (26) is aligned with a radially extending row of longitudinal channels (22). consequently each of the channels of the first set of channels (23) orthogonally intersects one or more adiacent longitudinal channels (22) in a radially extending row of longitudinal channels, 0066] A second se of channels (24) is prnvded on at least one of 26a) (Figures 5 to 8). In figures 5a and 5h, the secona set of channels (24) is provided on The perimeter face (26) of a right circular cylinder, in which the longitudirial channels (22) are provided as a square array. ln figure ea the first (23) and second (24) sets of channels are provided on a Mt perimeter face (255) of a right square cylinder having a square array of longitudinal channels (22), A third set of channels (37) is provided on a perimeter face (26b) trat is orthogonal to the perimeter face (2$5) on which the first (23) and second (24) sets of channels are provided The third set of channels (37) extends in a direction that is orthogonal to both the longitudinal channels (22) and the second set of channels The third set of channels (37) orthogonalty intersects with both the longitudinal channels (22) and the second set of channeis (24). This is illustrated in figure 6b, where the alignment of the alignment of the second (24) and third (37) set of channels relative to the longitudinal n s(22) and the offset 01 the first (23) and second (24) set of channets relative to,h other is shown. An emoodimont in which a right square cynaer is proviced with first (2) atid second (24) channels only (over the seine end face) is lliustratec in figure 60. The second set of channels (24) comprises laterally extending rows of of Is (24a) (as illustrated by the dotted line in figures 5a, eb. Band 7) and longitudirt liy extending, rows channels (24b) (also illustrated by the dotted line in figures ea So Ga, eh, Sc and 7). The laterally extending, rows of channels (24a) extend over the perimeteface (26, 26a) around the circumference of the body (15) Each of the channels in the laterally extending rows of channels (24a) is aligned with a channel in the row above so that the second set of thannels is also defined by longitudinally extending rows of channels (24b), each row extending longitudinally betwee,n the first (18) and second (21) end faces, Each of the rows of channels of the second set of channels (24) is offs& from and interspersed between adjacent rows of the first set of channels (23). Preferably each of the channels in the second set of channels (24) is longitudinally and laterally offset from each of the channels in the *first set of channels (23). This ts illustrated in each of figures Sc, 5b. ea, 5b, 6c and 7 where a can be seen that where a perimeter face contains MU sets of channels (23, 24) each channel of the first set* of charineis (23) is surrounded by four channels of the second set (24) and each channel of the second set of channels (24) ls surrounded by four channels of the first set of channels (23), Each of the channels of the second set of channels (24) extends from one perimeter face (26) through the body (15) to an opposite si.de of the body (15) in a direction that is both substantially parallel to a plane defining a first (18) or second (21) end face and substantially perpendicular to the longitudinal axis (L) of the body (15), Each of the channels of the second set of channels (24) essentially passes between the volume occupied by two laterally adjacent rad ally extending rows of longitudinal channels (22) each row extending in a radial direction through the body (15)). Since the diameter of each of the channels in the second set of channets (24) is chosen to be laier than the spacing between the outer edges of adjacent lonoitudinel channels (22), each channel of the second set or channels (24) intersects each of two laterally adjacent longitudinal channels (22) at their edges. In this way a longitudinally extending row of the second set of channels (.24) intersects with substantially all the channels in the laterally adjacent radially extending rows of longitudinal channels (22). This form of intersection is referred to throughout as tangential intersection: each channel of the second set of channels (24) intersects the adjacent orthogonally extending longitudinal channel (22) at opposite edges of its circumference.

[00671 The arrangement of the first (23), second (24) and optionally third (37) set of channels relative to the longitudinal channels (22) is illustrated in figures 14a. 14b and 14c, which is a sectional view in a direction locking down end face (21). Longitudinal channels (22) are viewed from bebw anti extend away from the page, Channels (23) of the first set of channels extend in a direction parallel to the page and pass through or directly intersect radially adjacent longitudinal channels (22) in an orthogonal direction, so that the angle of intersection between a line defining a central axis of any one of the first set of channels (23) vvith that of a line defining a central axis of any one of the longitudinal charmels (22) is substantially perpendicular. Each of the channels of the second set of channels (24) are laterally and longitudinally offset relative to the first set of channels (23) and extend in a direction substantially perpendicular to the longitudinal axis of the body (L.). The channels of the second set (24) are wider than the spacing between adjacent longitudinal channels (22) A lateral offset of the second set of channels (24) relative to the first set of channels (23) within the body (15) means* that each longitudinally extending row (24b) of the second set of channels (24) extends*between the volume defined between laterally adjacent radially extending rows of longitudinal channels (22) and merge or tangentially intersect with these laterally adjacent radially extendirig *rows of longitudinal channels (22) at their opposite edges. The configuration of the first and second set of channels (23. 24) relative to the bngitudirtal channels (22) within the body f15) has, the advantage that the body 05) is characterised by an internal surface that has a high surface area, which is capable of being substantially fully irradiated bY light emitted from a UV light source (7) placed within recess*(8) A component (3) including a photocatalyst is therefore able to support rapid and high conversion of toxic gases and pollutants exposed to the continuous surface of the body (15) to less hermiet species toimpreve the environment, 100681 In figure 14a, the first (23) and second (24) sets of channels extend substantially parallel to each other and substantially perpendicular to the longitudinal channels (22); this is essentially the internal arrangement of channels within the body depicted in figure 6c, In figure 14b, the first set of channels extends in a direction that is substantially orthogonal to both the direction in which the second set of channels (24) extends and the direction in whi.Ch the longitudinal channels (22) extend, In figure 14c. the first (23) and second (24) set of channels extend in a direction that is substantially parallel to each other and which is substantially orthogonal to the direction in which both the longitudinal channels (22) and the third set of channels (37) extend furthermore the third set of channels (37) extends in a direction that is substantially orthogonal to the direction in which the longitudinal channels (22) extend 100891 In a preferred embodiment, each of the chanriels in the first, second artd third set of channels (23. 24, 37) extend in a direction that is substantially perpendicular to the direction of the longitudinal axis (L). That is to say the longitudinal axis (L) intersects or passes the a central axis defined a&ong the length of each of the channels of the first (23): second (24) and third (37) sets of channels at 901 However each of the first(23), second (24) and third (37) sets of channels may extend at an angle of greater than 90 relative to the longitudinal channels (22), for example 90 to 109', preferably 90 to 1Q2, more preferably 90 to 95' and especially 90 to 92 This means that if the first end face were considered to be an upper end of the body and the second end face the lower end, the first (23). second (24) and optionally third (37) sets of channels would essentially be configured in a clownwand direction relative to the longitudinal channels (22), This has the advantage of improving airflow through the body (15).

10070] An especially preferred embodiment of the invention* is illustrated in figure 6b. The body (15) is derived from or provided in the form of a right equate cylinder having a square array of longitudinal channels (22) arranged over each of the first (18) and second (21) end faces. A first (23) and second (24) set of channels are provided over perimeter face (284 The first set of channels (23} are laterally and longitudinally offset from each other 5o that each channel of the first set (23) is surrounded by four channels of the second set (24) and each channel of the second set (24) is surrounded by four channels of the first set (23) A third set of channels (37) is provided on perimeter face (28b), *which is orthogonal to perimeter face (26a), Each of the channels of the third set of channels (37) aligns with ons or more longitudinal channels (22) extending between the first (18) and second (21) end face and intersects therewith in a substantially orthogonal fashion. Similarly each channel of the third set of channels (37) aligns with one or more channels of the second set of channels (24) provided on perimeter face (25a) and intersect therewith in a substantially orthogonal fashion.

[00711 In an alternative embodiment. the longitudinal c.hannels (22) are provided in the form of a circular array over the end faces (18. 21) of a right circular cylinder. Each end face (18, 21) comprises both concentric and radial rows of longitudinal channels (22). The first (23) and second (24) sets of channels are provided as rows of channels. such extend both laterally and longitudinally over Perimeter face (26) Each row of channels of both the first (23) and second (24) set of channels also extends in a radial direction that is substantially perpendicular to the longitudinal axis (L.) of the body (15). Each longitudinally extending row of channels of the first set of channels (23) orthogonally intersects a one or more channels (22) in a radially ey,tending row of longitudinal channels (22). Each longitudinally extending row of cnannels of the second set of chanritels (24) tangentially intersects one Or more channels (22) in two laterally adjacent radially extending rows of longitudinal channels (22) The third set of channels (37) extends coplanar with the direction in which the second set of channels extends and follows a line defined by a circular row of longitudinal channels In this way the third set of channels orthogonally' intersects one or more longitudinal channels (22) in a circular row and one or more channels from the second set of channels (24) [0072] Figures 2. 3 and 4 illustrate the arrangement of the longitudinal channels (22) in the body. The lohnitudinai channels (22) extend through the body (15) from a first end face (18) to a second end face (21). The channels (22) are provided as an array of channels over each of the end faces (18, 21) and are preferably centrally arranged around a central longitudinal axis (L). In figure 2, the each of the longitudinal channels (22) extend in a direction that is both substantially parallel to the direction of the central axis (L) and to that of each of the other longitudinal channels (22) The channels (22) e.xtend in a direction that is also substantially parallel to the location of the recess (6) wlthin the body (15), in figure 3 the longitudinal channels (22) curve away from a central axis (14 as they extend along the body (15) from the first end face 18) to the second end face (21). This may improve the flow of the gases being treated through the body (15) in figure 4, the diameter of the longitudinal channels *(22) increases as they extend from the first end face* (18) to the second end face (21). As before this feature may improve the flow of the gases being treated through the tiody (15), 100731 The body (15) may be provided in the form of a right circular or efflpticl cylinder (figures 5a and 51), a right square or rectangular cylinder (figures ea, 6b and 60) or a right hexagonal cylinder (figure 7). Other shapes such as a penteobnal or heptagonal pism may also be; envisaged. The longitudinal channels (22) are suitably provided as an array over each of the end faces (18, 21) The longitudinal channels may be arranged over each of the e,nd faces (18. 21) as a square array of channels (figures 5a. 51,, 6 and 11) QV as a radial array (figures 7th 10) 100741 Square arrays of channefs are best illustrated in figures 5b. Sc, 6 and 11 where each of the channels (22) are arranged as aligned rows over each end face, the longitudinal rows (22) extending in both the x direction and the y-direction. By the term "aligned rows-it should be understood to mean that each of the channels in any one of the rows is positioned immediately adjacent channels in any preceding or subsequent row (00753 Radial arrays are iii.istrated in figures? to 10, Radial arrays comprise circular rows of channels (22a. 22b, 22o; figure g) radially distributed about a central axis (t.) extending the length of Inc cylindrical body (15). The circular rows of channels (22a, 22b. 22c) are radially aligned so that each chaiiner in any one of the circular rows is positioned immediately adjacent a channel in any preceding or subsequent row, In this way the radial arrays define both circular rows of channels (22a 22b, 22c) and radially extending rows of channels (22x, 2'2y, 22z). each radial row extending from an axis defining the centre of the body (15) towards a Perimeter face (26), By the tenn 'circular rows of channels it is to be understood to include rows of channels of any geometric shape, whose configuration follows that of the perimeter defined by the shape of the body (15), For example, it can bo seen that the component (3) of figure 7 comprises a right hexagonal body 1)5; comprising Signed hexagonal rows of channels l22) radially distributed about a central axis of the body (15), Radially extending rows of channels can also be seen. All of the longitudinal channels (22) in the radial arrays may have substantially identical diameters at each end face (18, 21), figures 7, Band 9. Alternatively, and as seen in figure 10, the diameter of the channels of the outer circular rows of channels icloser to the perimeter of the end face) may be larger than those of the channels (22) closer to the middle of the end face, An advantage of this arrangement is that it maximises the surface area available for supponing the catalyst. [0076] The recess (a) configured to receive the UV light source (7,1 is, as Mustrated in figures 1 to 4, 5a and 7 to 11, preferably located 'along a central axfs defined by the body (15), However other configurations are envisaged and, as illustrated in ftg,ure 12, the body (16) may be provided with more than one recesses located over the first end face {18) extending from the first end face (18) towards the second end face (21), Alternatively, and as illustrated figure 17, the body (15) may include a helical recess extending from the first end face (18) towards the second end face (21), the hefical recess being configured to receive a strip of LED liehts that emit light in the UV range of the spectrum, [0077] In use the component (3) comprising the body (15) and the photocatatyst is located in a housing (2) to give an air-treatment unit configured for use in an air-treatment system. As illustrated in figures 2 and 15, the housing (2) comprises an inlet (4) and an outlet (5), a housing wall (27) extending between the inlet (4) and the outlet (5), the housing wall comprising an exterior surface (28) and an interior surface (29). the interior surface (29) defining an enclosure (3Crt: the enclosure being configured to receive the component (3) of the first aspect of the invention and to provide an air passage to support the flow of air in a longitudinal direction (defined by arrows A<" A) between the inlet (4) and the outlet (5), Preferably the housing also comprises means (a) for facilitating airflow -between said inlet (4) and said outlet (5), The housing may optionally also be provided with a filter (12) and a bracket CIO) to support a UV light source The means for facilitating airflow include fans, baffles and air funnels (34), Examples of fans that can be used in this application include an axial fan, a centrifugal fan and a cross-flcvst fan, Air funnels can be provided in applications of the type illustrated in figures 19 and 20 Where the air treatment unit is incomorated into the roof (k.sture 19) or bonnet of a car (figure (20)). In both cases the housing (2) includes an air funnel (34) at its inlet Air entering the housing (2) via the air funnel (34) impinges on turbines (35)-The transfer of kinetic energy between the incoming air and the turbines causes generators (36) to produce electrical energy that powers a UV light source (7) located wlfimn the recess (6) of component (3), irocrrai A photocatalytic coating, may be provided on the:rmer surface (29) of the housing (2). This bas the advantage of increasing the amount of photocatalyst that can be supported in the unit (1) to increase the conversion of toxic gases and pollutants passing through the unit (1) to less harmful substances. Alternatively. or in addition the inner surface (29) comprises a reflective material, This has the advantage of reflecting any light escaping from the perimeter face (26) back towards the interior of the body (15), thereby improving the efficiency of the conversion process The interior surface (29) of the housing (2) may be smooth or may configured to improve the airflow through the housing (2) In this respect the interior (29) of the housing (2) may. as illustrated in floures 15. 16 and 18 include ncig,as (31) and troughs (32). The ridges (31) and troughs (32) may be configured to extend in a rep,eating pattern Wong the length of the housing (2) between the inlet (4) and the outlet (5) (figure 15) or they may he configtired to extend in a reNating pattern around the intenor surface (29) of the housing, (2) Alternatively, and as illustrated in figure 18, the housing may tr,rnprise a series of ridges (31) arid troughs (32), whch extend in a repeating helical configurahon along the length of the housing (2). The troughs (32) may be configured to receive one or more sources of UV light (33) The sources of UV light (33) may be provided as strips of LED lights that extend laterally (figure 15), longitudinally (figure 16) or helically (figure 18).

[00801 in use air including a source of toxic gases and pollutants passes through the inlet (4) and over and through component (3) where the toxic gases and pollutants are converted to less harmful substances The improved. conditioned, treated or purified air then passes through outlet (6) and is eventually released from the system, Where the air-treatment unit is installed in a fixed location, such as a vehicle exhaust system. a building or at the side of a road, the means for providing a flow of air through the housing is preferably a fan The fan may be located at the inlet (4) or outlet (5) but is preferably located at the outlet (5). Where the air treatment unit is installed in a movable location, such as on the roof or bonnet of a vehicle, the means for providing a flaw of air through the housing is suitably an air funnel which directs the airflow generated by the moving vehicle into the housing ard over the component.

[0081] Examples

[0082] A polyamide component having a structure in accordance with the first aspect of the invention coated with a photocatalyst as disclosed in United Kingdom patent application no GE32012145.5 was located in.a housing to form a unit A UV light source was focated in the recess of the component The component is characterised by a square array of longitudinal channels extending from the first end face to the second end face. Each of me channels of the longitudinal channels has a diameter of 5rnm and a centre to centre spacing of 7.5mm. The component is derived from a right square cylinder and is shaped to a right circular cylinder. A first set of channeis extends from what would have been one face of the right square cylinder and extends to the opposite face. The channels of the first set orthogonally intet-sect the longitudinal channels. This is illustrated in figure 6b. Each of the channels of the first set of channels has a diameter of 4rnm and a centre to centre distance of 9,7cm. A second set of channels extends from the same face as the first set of channels and extends in a direction that is substantially parallel therewith The channels of the second set ta.nQeCIti.afl.y intersect tw -ally adjacent rows of longitudinal channels, b'oth the first et of channels and the second channels comprise. aligned laterally and longitudinally extending rows of channels arranged over the opposing penmeter faces. The rows of the channels of the first set of channels are interspersed and offsot from the rows of channels of the second set of channels, This means that each channel of the first set of channels is surrounded by four channels from the second set of channels as-viewed from the opposing perimeter faces and each channel from the second set of channels is surrounded by four channels from the first set if channels. Each of the channels of the second set of (man/lets has a diameter of 5inm and.a centre to centre spacing of 7.5mm. A third set of channels extends between the perimeter faces orthogonal to the perimeter faces between which the first and second set of channels extends. Each channel in the third set orthogonally east one iongitudinai channels and at least one channel from the second s channels. Each of the channels of the third set of channels has a diameter of 5rnm and a centre to centre spacing of 7.5mm. The component of the first aspect of the invention has a al surface area of 35066 rn2 and an internal air volume of -1 5725m total surface aica to volume ratio of 0 46, A fan was fitted adjacent the housing outlet 5) A pollution source was created by burning butane gas and cigarettes in a closed room for 150 minutes, Monitors capable of detect:ng carbon dioxide and particulate materials having a diameter in the range from under 1Prn to 10Prn (PM1, PM2.5, PM4 and PM10) were fitted to the inlet and the outlet of the housing, The fan was turned on and the levels of carbon dioxide and particulate matter detected at the outlet were monitored over a period of 135 minutes, The efficacy of the unit including the component (3) at removing carbon dioxide and particulate matter from the air Source was calculated The experiment was repeated using a component as above, which was not coated with a photocatalyst The experiment was further repeated using a component having*a split-P TPMS configuration coated with the photocatelyst; the split-P component is characterised by a total surface area to air volume ratio of.0175.. The results are shown in tables 1 to 5 below and also in figures 22 to 26. [0083] Table 1. a comparison of the change in COQ levels achieved using (1) the photocatalyst-coated poiyamide component of the present invention (2 an uncoate having a configuration according to the present inventlon. and (3) a photocatalyst coat polyarnide body having a split-P TPMS structure I 3831 CO2 (porn) 0 1 5181 tl) PCO No PCO (3) Split P pm) CO; (PPM) 71462 2568 4283, 2413 i 4001 2460 3756 2322 [00841 Tabie 2: a comparison of t e change in PM.; ievels achieved using C photocatalyst-coated polyamide component of the present invention; (2) an.ncoted body having a configuration according to the present invention; and (3) a photocatafyst coated,poiyamicie body having a sprit-P IPMS structure-. 2283 '1075

Reduction I Average I change 2 4O 44.6% 2720 1 2494 1493 2180 325'7 1520 1 (2) No PCO (1) PCO PM1 uoki 216.8 2 215.6 209.6 185.1 17/ 6 166,6 Reduction % reduction 53 'Table 3. a comparison of the change in PM;5 ievels achieved pholocatalyst-coated poiyainide component of the present invention 200.9 208 i 104,7 10,4%1 24.9 203,6 200 6, 199.4 I 194,9 22,6 218 5 216.4 214.2 212.4.1 210,3 207,7 16.6 (1) the n coated I Split 11 uoinis 224 3 224 6 222.5 r ody having a configuration accorthng to the present invention; and (3) a 'Thotocatelyst coated polyamide body having a split-P 'MIMS structure.

(1) PCO (2) No P L (3) Spilt P P11.42.5 ug(rn PM2.5 u9isn3 PM2 5 Ligi.r& 0 1 333 6 339.5 1 3C4: 33(.1,1 i 287.1 324.4 208.4 8 250.5 230 2 21T8 304.31 289.9 348 6 4.6 1 511 4 33 327 3 320.5 14.3 211.1 283:4 30851 2042, 27841 302.3 difference 67,6 129,4 60.7 L 0./.; reduction 38.8'm 17.9% 16.0% 00881 Table 4: a comparison of the change in PM.4..eveis achieved using (1) the photocatalyst-coated polyernide component of the present invention; (2) an uncoated body having a configuration according to the present invention: and (3) a photocetalyst coated polyamide body having a split-P TPMS structure.

PCO No PCO Split p Minutes P1\14 udinrY PR4u3hns PM4 U911:11 368.1 0 352 32'1 9 347 5 296,9 341 I 45. 331,1 -F.tric 8 325.5 I 23a 5 318.1 i 226 i 312 5 220,1 1 301.9 --, i 294,8 2123 i 28a4 205.2 Reduction... 146.8 i i % reduction 68 7 [ 1,9.2% i 41.7%.L PCO No PCO Split P Pf1,110 tic/1m' Minutes PM 1 b Li gim3 NM 0 ugini 0 348,8 351.4. 383 9 317.9 346 3752 292.8 3353k 387 116 325,5 355.4 252:4 320.3: 349:4 231.1 a Le. 340,6 N. 223.4 306 9 332 \ 217.8 296,7 3246" 12C) 210.1 289,6 318 6 202.2 2838! 310 387.4 3E2 8 371.3 360:1 360 1 354.1 1 345,2. 3366j 329.3] i 322.7 I 315.2 1: 72 2 i 18,8% [00871 Table 5. a comparison of the change* in PM:4; levels achieved using (1) the photocalalyst-coated pofyarnide component of the present invention; (2) an uncoated body having a configuration accordtng to the present invention: and (3) a photocatalyst coated Polyamide body having a split-P IP-MS structure, reduction[ 146.6 67.6 73.4 I % reduction 42.0% 19.2%1 [0088] it can be seen from the foregoing that when the component of the first aspect of titie invention is included iii an air treats/lent unit, it is able to remove toxic gases such as carbon dioxide and pollutants such as particulates from an air source in many cases more than twice as effectively as the uncoated (control) component and also as the coated component having a TPMS Split-P configuratim

[0089] Example 2

[0090] Comparison of Matrix Structures posij A.Proster hand-held anemometer was used to study the pattern ot air movement at the inlet and outlet ports of air-treatment units comprising the component of the present invention arid a component havino a TPMS split-P structure. In a general case air entering the system is relatively laminar, whereas air leaving the system is relatively turbulent as it is forced to mix with Cr open body of air. It was noted that the air exiting a unit:ncluding the component of the present invention was more laminar than air exiting a unit including the IPMS solit-P component. The anemometer showed that numerous counter-rotating odd:8S were formed at the inlet with the split-P matrix, which were entirety absent with the component of the present invention. It would therefore appear that the component of the present tnvention is characterised by improved airflow compared to the TPMS spit ' cornponent.

Claims

Claims A component (3) for an air-treatment unit (1). the component (3) comprising a photocatalytic material and a solid body (15). the solid body (15) comprising: a. an inlet (16) defined *by a first end (17) irmluding a first end face (18) an outlet (19) defined by a *second end (20) including a second end face (24 and one or more perimeter walls (25) defining one or mare perimeter faces (26) extending between the first end (17) and the second end (20), L' . a OlUrality of longitudinal channels (22) extending through the body (15) from the first end face (18) to the second eno face pi), the longitudinal channels (22) defining a longitudinal direction for the flow of air through the body (15). the channels (22) extending substantially parallel to each other along the longin.idirtal direction over at least part of the length of the body (15); a first set of channels (23) comprising a piurality of rows of channels provided over at least one of the perimeter walls (25), said rows extending laterally and being aligned in a longitudinal direction over the at least one perimeter wall (25), each of the channels (23) of the first set extending radially from a per irrieter face of the at least one of the persineter wells (25) through the body (15) towards an opposite side of the body (15) in a direction substantially perpendicular to the dirction of the longitudinal charmers (22). each cnannel of the first set of channels (23) being configured to orthogonally intersect a radially extending row of one or more adjacent longitudinal channels (22). the row of longitudinal channels (22) extending in a direction substantially parallel to the direction in which the channels cite first set (23) extend; d. a second set of channels (24) provided over at least one of the perimeter walls (25) and comprising a plurality of rows of channels, said rows extending laterally and being aligned in a longitudinal direction over a perimeter face of the at least one perimeter walls (25), each channel of said second set (24) extending from the perimeter face.of the at least one perimeter walls (25) through the body in a direction substantially perpendicular to the direction of the longitudinal channels (22), each of the rows of the second set of channels (24) being dispersed between the rows of the first set of channels (23) and laterally off-set therefrom, each channel of lIe second set (24) being config;..red to tangentially intersect two laterally adjacent radially extending rows of iong':tudinal channels (22): the rows of longitudinal channels (22) extending in a directors substantially parallel to the direction in which the channels of the first set (23) extend, the first set of channels (23). second set of channels (24) and perimeter wall G25) defining a substantially continuous surface having a Pliefocatalytic material supported thet'eon; and a. a recess (6) for receiving, a UV light source (7) within the body.
2. A component (3) according to claim 1. whereln the body (15) further comprises a third set of channels (37), each channel of the third set of channels (37) being configured to orthogonally intersect one or mere longitudinal channels (22) and to *orthogonally lntersect one or more channels from the second set of channels (24), 3, A component (3) accordinglo any one of the preceding claims, wheretn the first set of channels (23) comprises substantially parallel rows of channels extending laterally and longitudinally across the perimeter face (26) of the perimeter wau (25), 4, A component (3) according to any one of the preceding CiairnS, wheten the second set of channels (24) comprises substantially parallel rows of channels extending laterally and longitudinally across the perimeter face (20) of the perimeter wall (25).S. A component (3) according to any one of the preceding claims, wherein the longitudinal channels (22) are preferably provided in the form of an array extending over eac..ti of the first (18) and second,'21) end faces.6. A component (3) according to claim 5, wherein the array is a square array A component (3) according to claim 5, wherein the array is a circular array.8, A component (3) according to any one of the preceding claims, wherein the continuous surface is characterised by a surface area and an internal air volume and the ratio of the surface area to the internal air voluine is 0410 0,8 9. A component (3) according to any one of the preceding claims, wherein the photocatalytic material supported on the surface is a mixture of zircomum and ceri UM oxides.10, A housing (2) for.a component (3), the housing (2) comprising an inlet (4) and an outlet (5), a housing wall (27) extending between the inlet (4) and the outlet (5). the housing wall (27) defining (i) an enclosure (30) for receiving a component (3) according to any one of claims Ito 11; 01) an air passage between the inlet (4) and the outlet (5) and (tir,t a longitudinal direction defining the flow through the housing (2) between said inlet (4) and said outlet (Si, the housing (2) further comprising means for facilitating airflow between said inlet (4) and said outlet (5), A housing (2) according to claim 10, wherem the housing wall (27) comprises an outer surface (28) and an inner outface (29) configured to face the enclosure 00) and a photocatalytic coating is provided on the inner surface. (29) of the housing (2).12. A housing according to claim 11, wherein the inner surface (29) of the housing (2) composes a reflective material.13, A housing (2) acceding to any one of claim 10 to 12, wherein the surface (29) of the housing (2) *comprises ridges (31) and troughs (32).14. A housing according to claim 13, wherein the troughs (32) are configured to receive a source of UV ligfit (33).1c, An air treatment unit (1) comprising a component (3) according to any one of claims 1 to 9 and a housing according to any one of claims 10 to 14