An Indian Journal. Full Paper. Trade Science Inc.

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1 Tade Science Inc. July 006 Volume 1 Iue 1 CTAIJ, 1(1), 006 [8-1] Specific Heat Capacity Of Some Mineal, Syntetic And Semi-Syntetic Automotive Lubicant Oil Afte Temal Degadation Coeponding Auto Joé Calo Oliveia Santo Unidade Acadêmica de Educação, CES Univeidade Fedeal de Campina Gande, UFCG, , Cuité, Paaiba (BRAZIL) Pone/Fax: zecalouepb@yaoo.com.b Received: 1 t Mac, 006 Accepted: 8 t June, 006 Web Publication Date : 7 t July, 006 Co-Auto Antonio Gouveia Souza Depatamento de Química, Cento de Ciência Exata e da Natueza, Univeidade Fedeal da Paaíba, Campu I, Cidade Univeitáia, , João Peoa, Paaíba, (BRASIL) ABSTRACT Te knowledge of te pecific eat capacity of te deived of te petoleum and of it mixtue it i of geat pactical impotance in te banc of te petocemical engineeing, becaue it i aociated wit te efiney opeation of petoleum and ote coelated pocee. Ti wok aim to caacteize temal degadation poce of automotive mineal, yntetic and emi-yntetic lubicant oil, in elation to it pecific eat capacitie. Lubicant wee degaded at tempeatue vaying fom 10 to 10ºC, and time of 1 to 8 ou. Afte degadation, oil wee caacteized by DSC. Te analyzed lubicating oil peent an inceae in you eat tanfe capacity in function of te inceae of te tempeatue. 006 Tade Science Inc. - INDIA KEYWORDS Lubicant; Degadation; Specific eat capacity; Caloimety. INTRODUCTION Moden lubicant, wit ig pefomance, can do muc moe tan imply educing attition and wea. Lubicant oil ae eally impotant, peenting diffeent function, a efigeation, cleaning, fencing off and potection againt cooive agent [1]. Lubicant oil degadation unde opeation condition i a poblem tat involve meaningful economical loe. Oxidation i te pimay agent of degadation, and a given ie to many tudie. Etabliing temodynamic paamete of eaction i difficult due to complexity of tee ytem [-]. It i of fundamental impotance to know te temal beavio of te automotive lubicant oil, tei cemical compoition and pyical popetie fo a

2 CTAIJ, 1(1) July 006 tict poce contol and te definition of tandad fo eac pecific ue []. Te pecific eat capacity (C p ) i a one of uc pyical popetie. Te mola eat capacity a a geat impotance in temocemical pocee and it i elated to te eat of tanfomation, dq P, at a contant peue, p, a own below in Eq. 1: dh Q p (1) a Q p depend on te eat excange and doe not depend on te eveibility of tee pocee, te pecific eat capacity (Cp) i defined by Eq. : dh Qp Cp () dt dt Te knowledge of te pecific eat capacity (Cp) of te deived of te petoleum and of it mixtue it i of geat pactical impotance in te banc of te petocemical engineeing, becaue it i aociated wit te efiney opeation of petoleum and ote coelated pocee [6]. In te development of te equipment, te knowledge of te pecific eat capacity value, in eveal tempeatue inteval, i of fundamental impotance, becaue tee data can elp in te etabliment of condition of lingeing toage o of opeation to low tempeatue. Te pecific eat capacity can be ued fo evaluation of ote baic temodynamic popetie of ote fuel [7]. Conitent expeimental data about te pecific eat capacity of deived of te petoleum ae quite limited in te liteatue, and ome data ae available in mall tempeatue inteval fo te geat majoity of tee deived. Diffeence in te compoition of te automotive lubicant oil can eult in ignificant diffeence in it pecific eat capacity. In te lat yea, te Diffeential canning caloimety a been enoug ued in te detemination of te pecific eat capacity of ydocabon mixtue [8]. Ti appen; teefoe toug ti metod it can be obtained eult wit geat enibility and peciion. In te peent wok, te pecific eat capacitie of ome automotive lubicant oil wee detemined by Diffeential canning caloimety afte temal degadation, to evaluate te popoed metod. Joé Calo Oliveia Santo and Antonio Gouveia Souza 9 EXPERIMENTAL Te ample of automotive lubicant oil wee acquied in te local tade, being all poduced by Bazilian indutie. In ti tudy, mineal lubicant oil wee ued wit and witout addictive, yntetic and emi-yntetic (mixed), all detined to te application in te gaoline, alcool and natual ga moto, woe caacteitic ae decibed in te TABLE 1. Fo temal degadation, lubicant wee eat teated at 10, 170, 190 and 10ºC, wit ai flux, in a ytem imila to a ditillation one, a peented in figue 1. An initial lubicant volume of 00 ml wa ued. Sample wee witdawn afte time tat vaied fom 1 to 8 ou. Specific eat capacitie wee evaluated fo degaded and non-degaded lubicant oil. Figue 1: DSC cuve: (a) lubicant oil ample, (b) blank and (c) efeence mateial DSC meauement A diffeential canning caloimete Simadzu, model DSC-0, wa ued. Te automotive lubicant oil ample wee placed in aluminum cucible and eated fom oom tempeatue up to 190 o C at a eating ate of o Cmin -1, unde a dynamic atmopee of nitogen (0 mlmin -1 ), accoding to te pocedue decibed in TABLE. Tee meauement wee caied out fo eac ample: 1) Meauement wit an empty cucible; ) Meauement wit a efeence mateial (alumina),

3 10 Mineal, yntetic and emi-yntetic automotive lubicant oil CTAIJ, 1(1) July 006 TABLE 1: Caacteitic of te analyzed lubicating oil Lubicant Bae Addictive Specification Mineal Paaffin Antiwate, antioxidant, detegent / dipeant, ut inibito and it kim, inceaed of te vicoity index API SJ SAE 0W Mineal witout addictive Paaffin Non contain API SJ SAE 0W Syntetic Syntetic Antiwate, antioxidant, detegent, dipeant, ut inibito and it kim, inceaed of te vicoity index API SJ SAE 0W/0 Semi-yntetic Paaffin and Syntetic Antiwate, antioxidant, detegent, dipeant, ut inibito and it kim, inceaed of te vicoity index API SJ SAE 0W/0 TABLE : Expeimental condition to detemine te pecific eat capacitie of edible vegetable oil Heating ate Tempeatue Time (ºC min 1 ) (ºC) (min) wit a known pecific eat capacity; ) Meauement of pecific eat of te lubicant oil ample, wit a fixed ma of mg. RESULTS AND DISCUSSION Accoding to Santo [], te elationip between eat capacity of te ample C (ample cucible uppot + ample cucible + ample), of te efeence mateial C (efeence mateial uppot + efeence mateial cucible + efeence mateial) and te eating ate ( ) i expeed a: T T C C () R wee T i te oil ample tempeatue; T i te efeence mateial tempeatue; R i te intument contant (temal eitance of te ample, efeence mateial and funace) and T - T i te DSC diplacement, wic i popotional to te diffeence between C and C. If te DSC diplacement i S and te popotionality contant i k, it can be tated tat: C C ks () Te automotive lubicant oil ample uppot and te efeence mateial uppot ave tei eat capacitie epectively epeented by C and C Te Figue : Scematic epeentation of te degadation ytem

4 CTAIJ, 1(1) July 006 pecific eat capacitie of te efeence mateial and of te lubicant oil ample ae epeented by c 0 and c, and te ma value of te efeence mateial and of te oil ample ae denominated m 0 e m, epectively. Tu, te following elation ae obtained: C C ks () ( C m c ) C ks (6) ( C mc) C ks (7) Wee S 1, S, S ae te temal diplacement of te DSC epectively elated to te blank, te efeence and te lubicant ample. Te figue ow te DSC cuve fo te lubicant oil ample, te blank and te efeence mateial. Fom equation (), (6) and (7) te following equation i obtained m mc S S 1 0c S 0 S1 Lubicant Oil Joé Calo Oliveia Santo and Antonio Gouveia Souza 11 (8) a te pecific eat capacity of te efeence mateial i known, te pecific eat capacity of te lubicant oil ample can be calculated by: m0c0 S S1 c m (9) S S 1 a S 1, S and S ae continuou function elating to te tempeatue, te pecific eat capacitie can be detemined continuouly []. Te TABLE ow te eult of ti analyi fo te ample of non-degaded lubicant oil. It can be veified tat te mineal lubicant oil peented a tanfe eat capacity of moe accentuated tat te yntetic and emi-yntetic oil. Ti fact i pobably due te cemical tuctue of tee ample, once, te mineal ae contituted baically of ydocabon in te tip fom 0 to cabon, wile te yntetic one, in you geat majoity, de- TABLE : Specific eat capacity of te non degaded lubicant oil Cp (J g 1 o C -1 ) 0 o C 60 o C 80 o C 100 o C 10 o C 10 o C 160 o C 180 o C Mineal Mineal witout addictive Syntetic Semi-yntetic Lubicant oil Mineal Mineal witout Addictive TABLE : Specific eat capacity of te degaded mineal baed lubicating oil Sample condition Cp (J g -1 o C -1 ) 0 o C 60 o C 80 o C 100 o C 10 o C 10 o C 160 o C 180 o C 10 o C/ o C/ o C/ o C/ o C/ o C/ o C/ o C/ o C/ o C/ o C/ o C/ o C/ o C/ o C/ o C/

5 1 Mineal, yntetic and emi-yntetic automotive lubicant oil CTAIJ, 1(1) July 006 ived of ete, and te emi-yntetic one, a mixtue of tee two type of oil. It i till veified, tat te peence of te addictive one (mainly addictive EP), it povoke an inceae in te pecific eat, due to te beaking of te lubicating film. Wit te eating, ti fact geneate a eponible eat fo te cemical eaction tat fee te compoition tat will act a lubicant. Te TABLE and ow te vaiation of te pecific eat capacity in function of te temal deg- adation of te automotive lubicant oil. Afte degadation of te ample, a vaiation a little ignificant i veified in elation to te pecific eat capacity in function of te time and of te degadation tempeatue, except fo te mineal lubicating oil witout addictive, tat it peent a fall in te pecific eat capacity value to 10 o C, due to te polymeization poce, becaue it wa obeved tat in ti tempeatue, afte 6 ou, te ample wa plenty of polymeized. TABLE : Specific eat capacity of te degaded yntetic baed lubicating oil Lubicant oil Syntetic Semi-Syntetic Sample Cp (J g -1 o C -1 ) condition 0 o C 60 o C 80 o C 100 o C 10 o C 10 o C 160 o C 180 o C 10 o C/ o C/ o C/ o C/ o C/ o C/ o C/ o C/ o C/ o C/ o C/ o C/ o C/ o C/ o C/ o C/ Non Degaded 10 o C/ 190 o C/ 10 o C/8 190 o C/8 170 o C/ 10 o C/ 170 o C/8 10 o C/8 6 Non degaded 10 o C/ 10 o C/8 170 o C/ 170 o C/8 190 o C/ 190 o C/8 10 o C/ 10 o C/ Figue : Specific eat capacity of te mineal lubicant oil in function of te time and degadation tempeatue Figue : Specific eat capacity of te mineal lubicant oil witout addictive in function of te time and degadation tempeatue.

6 CTAIJ, 1(1) July 006 Joé Calo Oliveia Santo and Antonio Gouveia Souza 1 Non Degaded 10 o C/ 190 o C/ 10 o C/8 190 o C/8 170 o C/ 10 o C/ 170 o C/8 10 o C/8 Non Degaded 10 o C/ 190 o C/ 10 o C/8 190 o C/8 170 o C/ 10 o C/ 170 o C/8 10 o C/ Figue : Specific eat capacity of te yntetic lubicant oil in function of te time and degadation tempeatue Figue 6: Specific eat capacity of te emiyntetic lubicant oil in function of te time and degadation tempeatue Te figue to 6 illutate te beavio of te pecific eat capacity of te automotive lubicating oil function of te time and degadation tempeatue. CONCLUSIONS In geneal tem, an inceae i veified, in all te cae, of te pecific eat capacity in function of te tempeatue, in te inteval of o C, getting to bend te pecific eat capacity. Te ignificant inceae appen tating fom te 100 o C. It can be veified altoug, te analyzed lubicating oil peent an inceae in it tanfe eat capacitie in function of te inceae of te tempeatue, ten tee lubicant oil be ued commonly elatively not in tempeatue vey dicage. In ige tempeatue, it appen a eating of te lubicated pat tat can cat you deteioation wit te time of ue of te lubicant. REFERENCES [1] M.S.M.Souza, Química e Deivado; 8, 0 (000). [] J.M.Peez; Temocimica Acta, 7, 7 (000). [] C.Kekin, M.V.Kok; Temocimica Acta, 69, 1 (001). [] C.D.Gamlin, N.K.Dutta, N.R Couduy, D.Keoe, J.Mation; Temocimica Acta, 9, 7 (00). [] J.C.O.Santo, A.G.Souza, M.G.O.Santo, J.P.Danta; Jounal of Temal Analye and Caloimety, 7, 19 (00). [6] A.Zanie, H.W.Jackle; Temocimica Acta, 87, 0 (1996). [7] T.Kapzycka-Guttmann, D.Odzeniak; Temo cimica Acta, 191, 1 (1991). [8] W.V.Steele, R.D.Ciico, A.B.Cowell, A.Nguyen, S.E. Knipmeye; Jounal of Cemical Temodynamic, 6, 97 (00). ACKNOWLEDGEMENTS Auto acknowledge CNPq, ANP and FINEP/ CTPeto by financial uppot of ti wok.