Document wDvkK7R7qv6kKR0y9z0w4NmEV

560 Dewalt Drive Pittsburgh. 3k, Pa Hay 6th, 1953 Dr. T.A.Boyd Research Laboratories Division General Motors Corporation Detroit 2, Michigan Dear Dr. Boyd: ' Following your very instructive and entertaining talk at the Pittsburgh Chemists Club last night, I would like to have talked to you about the recovery of lead bromide from the spent TEL in automotive fuel consumed. I believe my thoughts to be provocative but can see no practical way to achieve a profitable recovery. The automobiles themselves, together with the winds that blow have done such a job of distribution that the prospects for recovery would seem akin to G.H.Lewis* probability of unscrambling an egg by scrambling it long enough. .. We know that lead is,and will be the more so, in short supply. We also know the large amount of lead required to supply the national demand for TEL and the considerable amount of bromine required for ethyl fluid. : The thought occurs as to whether there are any sources where recovery of lead and bromine might be considered. Two sources which have intrigued me are as follows: ,. (l-X- Street sweepings in populous cities. Power sweeping is practiced ; in large cities and the refuse is presumably used for land-fill. The concentration of level bromide is: certain to be very small, perhaps too ,v small to warrant any work of extraction by leveling with hot water or by sublimation by heating. Classification processes involving air or wate. flotations might enter into a scheme of. separation. The organic \i matter in sweepings although probably not near as high as it was in the horse and buggy days, presents a problem in any recovery scheme . It might well be that the recovery process would become one of producing a soluble .. i / * insecticide for garden plants from extracting the cigars and cigarette butts. Bromine can, of,course, be freed from lead bromide using sul f'-P} furic acid and several schemes are available for the recovery of lead as such. : ( ' j.. . v . '7, ..V v;- e li v (3) Exhaust gases from vehicular tunnels. Presumably electrostatic pr e cipitation would give a concentrate of lead bromide which could be : 4:l ? j k worked into lead and bromine as already indicated. I had thought this If}.! source would yield sizable amount of these elements but ay calculations / concerning the Holland Tunnel proved disappointing end disuaded me from any , A Ikthought of going into the business. Here they are: ., - * . . 'r A `* K 0 0 1 3 9;-^ N\5316 -2- In 19^0, 13,331#159 vehicles uded the tubes Tunnel Is 1.6 Biles long. Assume lOOjt recovery of fines. 18 miles per gallon gasoline. 2 ml. ethyl fluid per gal. 6o volume TEL, Hojt ethylene bromide. TEL sp.g. 2.00 *ol. Tt. St Br2 sp.g. 2.18 mol.vt. 323*5 188. x 1.6 1.170.000 2.330.000 1,1*00,000 2.800.000 1,800,000 ,0 0 0 gal. gasoline x 2 ml, ethyl fluid x .6 T E L X 2.009mm- 4, S V W .... TELL X 2.08-- . Fhu, lbs. Fb. 2 , 3 ^ 0 0 0 ' ad o ethyl fluid x A 930,000 ml. St Brg x 2.18 2.180.000 gma.St.lr2 X'2&L.1Qg 1.860.000 gms. Br2 * H-,000 lbs. "25?. & V. 0M-k m ._ ...'j On .this basis, tvo tens of lead and tiro tons of bromine ^mlght be recovered per year, which is hardly a sizeable amount. .s. r It has been estimated that the sage of lead for anti-knoeh is 10^ of the total lead usage. .'It is about 1-l/V million tons per yeax. If evenly dls- tributed over the area of the continental Oaitecl States, it would amount to approsiaately l/2 tn per q.uarjgile.or 1^- lbs; per acre. While there will be anjchhlgher depositions in populous areas (one can arrive at,5 a figure of 5-t6as per square wile for the district of Columbia), I doubt1* ' .* . V 't '' ' <-i > 5;7rt' v-* V t-_ f * 'e ii 'X /* .h e " 00 ' ,,/ i- '. , . x -*--' ~ . y -*'<'** ------- ~9 *T \ Y ; since penetrated in some degree, the Jungles and deserts of all contin and both polar regions.' Much of the lead salt fuses is no doutofcwas] into the streams by rains, and, as with all mineral matter possessing \ . . degree of solubility, the lead salts must eventually concentrate inth< Of course, one might postulate each motorist recovering his bit of leax ,, salts by some collecting device attached to the exhaust system and a . collection system to round up the whole tonnage* This is hardly prac I ; ticable for a nuasber ^ r e a s o n s . } ' I thank you for having the patience to hear a out in this matter, (ass you have read this) and I would be interested inkhowijag vhat you,and any others with much experience in this field, think* . . . !"r v; Very'truly yours, _ ' . EVS/S ' ' ' Edwin W* Shaad ; , > V/.-``'l X'\ *! . vv 30^: j